26700
We find that at low dopant concentrations a large fraction of trivalent europium ions is unexpectedly present in the powders .
 Chemical: europium
Given options, please tell me the categories of all the listed entity words.Output format is "type1: word1; type2: word2". 
Option: Chemical 
Text: {0} 
 Entities: europium 
Answer:
 Chemical: europium