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Naturally occurring neodymium (60 Nd) is composed of five stable isotopes— 142 Nd, 143 Nd, 145 Nd, 146 Nd and 148 Nd, with 142 Nd being the most abundant (27.2% of the natural abundance)—and two radioisotopes with extremely long half-lives, 144 Nd (alpha decay with a half-life (t 1/2) of 2.29 × 10 15 years) and 150 Nd (double beta decay, t ...
In all, 35 radioisotopes of neodymium have been characterized up to now, with the most stable being naturally occurring isotopes 144 Nd (alpha decay, a half-life (t 1/2) of 2.29 × 10 15 years) and 150 Nd (double beta decay, t 1/2 of 9.3 × 10 18 years), and for practical purposes they can be considered to be stable as well.
Naturally occurring radioactive materials (NORM) and technologically enhanced naturally occurring radioactive materials (TENORM) consist of materials, usually industrial wastes or by-products enriched with radioactive elements found in the environment, such as uranium, thorium and potassium and any of their decay products, such as radium and radon. [1]
This is a list of radioactive nuclides (sometimes also called isotopes), ordered by half-life from shortest to longest, in seconds, minutes, hours, days and years. Current methods make it difficult to measure half-lives between approximately 10 −19 and 10 −10 seconds.
Unstable isotopes decay through various radioactive decay pathways, most commonly alpha decay, beta decay, or electron capture. Many rare types of decay, such as spontaneous fission or cluster decay, are known. (See Radioactive decay for details.) [citation needed] Of the first 82 elements in the periodic table, 80 have isotopes considered to ...
Solution containing Pm 3+ ions. Promethium belongs to the cerium group of lanthanides and is chemically very similar to the neighboring elements. [10] Because of its instability, chemical studies of promethium are incomplete. Even though a few compounds have been synthesized, they are not fully studied; in general, they tend to be pink or red ...
Neodymium compounds are compounds formed by the lanthanide metal neodymium (Nd). In these compounds, neodymium generally exhibits the +3 oxidation state, such as NdCl 3, Nd 2 (SO 4) 3 and Nd(CH 3 COO) 3. Compounds with neodymium in the +2 oxidation state are also known, such as NdCl 2 and NdI 2. Some neodymium compounds have colors that vary ...
Radioactive decay (also known as nuclear decay, radioactivity, radioactive disintegration, or nuclear disintegration) is the process by which an unstable atomic nucleus loses energy by radiation. A material containing unstable nuclei is considered radioactive. Three of the most common types of decay are alpha, beta, and gamma decay.