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Origin of the names and usage of the 17 rare earth elementsLanthanum (La)The element, “Lanthanum” is named in 1839 by Sweden Mosander, with the “didymia” in Greek when he found the elements in the ceria. From that on, lanthanum started to appear on the stage of history.The application of lanthanum is very extensive. For example, this element can be used in the piezoelectric materials, electro-thermal materials, thermoelectric materials, magneto-resistance materials, optical materials (such as the phosphor), hydrogen storage materials, optical glass, laser materials and other varieties of alloy materials, etc. In addition, lanthanum is also applied into the catalysts of many organic chemical products. The light-transformed agricultural film also adopts the lanthanum. ...