ISBN 978-0-8493-0485-9.\]ĭeuterium accounts for only about 15 out of every one million atoms of hydrogen. CRC Handbook of Chemistry and Physics (85th ed.). Half-life, spin, and isomer data selected from the following sources.International Union of Pure and Applied Chemistry. "News & Notices: Standard Atomic Weights Revised"."Atomic weights of the elements 2005 (IUPAC Technical Report)". de Laeter, John Robert Böhlke, John Karl De Bièvre, Paul Hidaka, Hiroshi Peiser, H.Isotopic compositions and standard atomic masses from:.Audi, Georges Bersillon, Olivier Blachot, Jean Wapstra, Aaldert Hendrik (2003), "The N UBASE evaluation of nuclear and decay properties", Nuclear Physics A, 729: 3–128, Bibcode: 2003NuPhA.729.3A, doi: 10.1016/j.nuclphysa.2003.11.001."Observation of new neutron-rich isotopes in the vicinity of 110Zr". "Identification of 45 New Neutron-Rich Isotopes Produced by In-Flight Fission of a 238U Beam at 345 MeV/nucleon". ^ a b Ohnishi, Tetsuya Kubo, Toshiyuki Kusaka, Kensuke et al.^ "Discovery by UMass Lowell-led team challenges nuclear theory"."Strontium-90 in environmental samples from Northern Germany before and after the Chernobyl accident". Journal of the National Medical Association. "Strontium 89 for Palliation of Bone Metastases". "Standard atomic weights of the elements 2021 (IUPAC Technical Report)". ^ Prohaska, Thomas Irrgeher, Johanna Benefield, Jacqueline et al.^ "Standard Atomic Weights: Strontium"."The NUBASE2020 evaluation of nuclear properties" (PDF). In 2020, researchers have found that mirror nuclides 73Sr and 73Br were found to not behave identically to each other as expected. Broadly speaking, atomic mass is based on the number of protons and neutrons in the nucleus of one atom of that element. These devices hold promise for use in spacecraft, remote weather stations, navigational buoys, etc., where a lightweight, long-lived, nuclear-electric power source is required. Because it is a long-lived high-energy beta emitter, it is used in SNAP ( Systems for Nuclear Auxiliary Power) devices. Strontium is most similar chemically to the heavier alkali earth elements, Calcium, and Barium. It causes health problems, as it substitutes for calcium in bone, preventing expulsion from the body. It has an atomic number of 38, an atomic mass of 88, one oxidation state (+2) and four naturally occurring isotopes ( 84 Sr, 86 Sr, 87 Sr, 88 Sr), of which 88 Sr is the most abundant at 82.6 of the total mass. The 1986 Chernobyl nuclear accident contaminated a vast area with 90Sr. ![]() is the only way of decreasing the amount of Sr-90 in the environment. Radioactive decay Radioactive decayThe process in which an unstable (radioactive) nucleus emits radiation and changes to a more stable isotope or element. Strontium-90 is a by-product of nuclear fission, present in nuclear fallout. Strontium-90 is widely dispersed in the environment and the food chain from atmospheric testing of nuclear weapons in the 1950s and 1960s. In circumstances where cancer patients have widespread and painful bony metastases, the administration of 89Sr results in the delivery of beta particles directly to the area of bony problem, where calcium turnover is greatest. Strontium-89 is an artificial radioisotope used in treatment of bone cancer this application utilizes its chemical similarity to calcium, which allows it to substitute calcium in bone structures. All other strontium isotopes have half-lives shorter than 50 days, most under 100 minutes. The longest-lived of these isotopes, and the most relevantly studied, are 90Sr with a half-life of 28.9 years, 85Sr with a half-life of 64.853 days, and 89Sr ( 89Sr) with a half-life of 50.57 days. Radioactive isotopes of strontium primarily decay into the neighbouring elements yttrium ( 89Sr and heavier isotopes, via beta minus decay) and rubidium ( 85Sr, 83Sr and lighter isotopes, via positron emission or electron capture). In addition to the four stable isotopes, thirty-two unstable isotopes of strontium are known to exist, ranging from 73Sr to 108Sr. Because strontium has an electron configuration similar to that of calcium, it readily substitutes for calcium in minerals. The ratio 87Sr/ 86Sr is the parameter typically reported in geologic investigations ratios in minerals and rocks have values ranging from about 0.7 to greater than 4.0 (see rubidium–strontium dating). ![]() Thus, there are two sources of 87Sr in any material: primordial, formed during nucleosynthesis along with 84Sr, 86Sr and 88Sr and that formed by radioactive decay of 87Rb. more than three times longer than the current age of the universe). ![]() Only 87Sr is radiogenic it is produced by decay from the radioactive alkali metal 87 Rb, which has a half-life of 4.88 × 10 10 years (i.e. The alkaline earth metal strontium ( 38Sr) has four stable, naturally occurring isotopes: 84Sr (0.56%), 86Sr (9.86%), 87Sr (7.0%) and 88Sr (82.58%).
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