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Lanthanum, like the other lanthanides, is known to affect human metabolism, lowering cholesterol levels, blood pressure, appetite, and risk of blood coagulation. When injected into the brain, it acts as a painkiller, similarly to morphine and other opiates, though the mechanism behind this is still unknown. [ 80 ]
Lanthanide metals react exothermically with hydrogen to form LnH 2, dihydrides. [1] With the exception of Eu and Yb, which resemble the Ba and Ca hydrides (non-conducting, transparent salt-like compounds),they form black pyrophoric, conducting compounds [6] where the metal sub-lattice is face centred cubic and the H atoms occupy tetrahedral sites. [1]
Lanthanide ions are used as the active ions in luminescent materials used in optoelectronics applications, most notably the Nd:YAG laser. Erbium-doped fiber amplifiers are significant devices in optical-fiber communication systems. Phosphors with lanthanide dopants are also widely used in cathode-ray tube technology such as television sets. The ...
The most stable of these is 154 Dy, with a half-life of approximately 3 × 10 6 years, followed by 159 Dy with a half-life of 144.4 days. The least stable is 138 Dy, with a half-life of 200 ms. As a general rule, isotopes that are lighter than the stable isotopes tend to decay primarily by β + decay, while those that are heavier tend to decay ...
The use of X-ray spectra (obtained by X-ray crystallography) by Henry Gwyn Jeffreys Moseley made it possible to assign atomic numbers to the elements. Moseley found that the exact number of lanthanides had to be 15, but that element 61 had not yet been discovered. (This is promethium, a radioactive element whose most stable isotope has a half ...
Most lanthanides can use only three electrons as valence electrons, as afterwards the remaining 4f electrons are too strongly bound: cerium is an exception because of the stability of the empty f-shell in Ce 4+ and the fact that it comes very early in the lanthanide series, where the nuclear charge is still low enough until neodymium to allow ...
The lanthanides are the 15 rare-earth chemical elements which lie between lanthanum and lutetium on the periodic table. The lanthanides are trivalent metals . Subcategories
Lutetium salts are known to cause metabolism and they occur together with other lanthanide salts in nature; the element is the least abundant in the human body of all lanthanides. [83] Human diets have not been monitored for lutetium content, so it is not known how much the average human takes in, but estimations show the amount is only about ...