30034
This operation mode is based on the previously - developed SPFM technique , though using water as the medium instead of air introduces some important practical and theoretical differences , and also greatly extends the applicability of this technique .
 None
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:  
Answer:
 None