Yttrium nuclides

An important reaction used quite widely for this purpose is irradiation by neutrons and measurement of die energies of radiations emitted. The source of the neutrons may be a nuclear reactor, a particle accelerator, or an isotopic source, that is, a sealed container in which neutrons are produced by alpha rays emitted by a source such as radium, sodium-24(24Na), yttrium-88f8sY), etc., and arranged so that the alpha rays react-with a substance such as beryllium which in turn emits neutrons. The neutrons react with stable nuclides in the sample to produce radioactive ones. Thus... 

A radioisotope battery is one of the choice for energy source of meteorological obseiwation and development of undersea and space[l]. We have considered a strontium-90 (half-life 28.8y) heat-source model of a radioisotope battery and improved it in two aspects—radiation dose reduction and improvement of thermal conductivity—adding graded structure to the model[2]. The present study reports the dose reduction of bremsstrahlung photons from -ray of - "Sr and its daughter nuclide yttrium-90. The calculation was carried out by a continuous energy Monte Carlo code, MCNP 4A[3]. 

Because this nuclide has 39 protons, its atomic number, Z, is 39. This identifies the element as yttrium. This nuclide of yttrium has 90 total nucleons (39 protons + 51 neutrons), so its nucleon number. A, is 90. 

If determination of the net B" -activity reveals that a measured value of 30 pCi/1 has been exceeded, a special analysis is to be performed to establish which nuclides have caused the radioactivity in the water. Of the radioactive fission products, strontium 90 represents the greatest danger to the organism. It decays as a B" -emitter with a half-life of approximately 28 years. Yttrium 90, which is likewise a B -emitter with a half-life of... 

If the presence of strontium 89 is suspected, or if the tolerance limit for strontium 90 is exceeded, the strontium 89 content must be taken into account. This can be effected for example by separating the yttrium 90 daughter nuclide formed from the strontium 90. With analytical and calibration solutions the yttrium 90 is separated from the strontium by way of precipitation with carbonate-free ammonium hydroxide following the addition of between roughly 5 and 10 mg of iron (III) solution as non-isotopic carrier. The hydroxides are washed out and prepared. The activity of the parent nuclide, strontium 90, and thus also the proportion of strontium 89 in relation to the total measured value can be calculated from the measured yttrium 90 activity. 

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