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Перевод: isotope

[существительное]
изотоп

Тезаурус:

1. The new ingredient in the assessment of how many deaths the Windscale cloud caused is the radioactive isotope, polonium 210.
2. Stable isotope analysis of white marble
3. However, normal mass spectrometers are not sensitive enough to detect sup14; C and to reject all other elements or molecules of very nearly the same weight, such as sup14; N. As this nitrogen isotope makes up some 80 per cent of the atmosphere it is very common relative to sup14; C. The techniques of nuclear physics were brought to bear on this problem in the late 1970s, and it was shown that sup14; C could be detected using what is now referred to as accelerator mass spectrometry, AMS.
4. In the early 1970s geological research highlighted the fact that lead ores carried distinctive isotope ratio signatures', depending upon the geological period when they were laid down as deposits.
5. Since we know that the periodicity of some variables is longer than the monitoring already carried out by human beings, we must make use of surrogate or proxy variables to extend our range of knowledge (such as via tree rings, palynology, oxygen isotope ratios from ice cores and geomorphological evidence of environmental change);
6. But what part of the body is affected can depend on which radioactive element the person is exposed to, and also which "isotope" - a specific atomic configuration of that element.
7. Strictly speaking, the isotope selection effect observed by the San Diego chemists is not the only one which can be independent of mass.
8. Both the isotope shift and hyperfine splitting are very small in comparison with average atomic transition energies.
9. But there was one isotope released in the accident that is highly mobile, that does have a high take-up by the human body, has a half-life of 140 days, and - though this was only revealed this week by the NRPB after New Scientist's inquiries - was released in significant quantities.
10. Another effect that can be measured is the "isotope shift".
11. This situation is quite different from the Windscale fire, in which the single isotope polonium-210 was released.
12. The discovery of the usefulness of lead isotope ratios was quickly applied to archaeology and has proved highly successful in provenancing lead-containing objects from antiquity.
13. In 1942, the British team led by Hans Halban was transferred to Chalk River in Canada where a British-designed pilot uranium isotope separation plant was to be built.