1796
Runs were performed with one or two transducers placed in vertical ( parallel or perpendicular ) and horizontal positions ( at the reactor base ) at 0 . 4 , 1 and / or 2 MHz ( specific energy 8 . 5 +/- 0 . 6 kJ / kg per transducer ) .
 None
Please list all entity words in the text that fit the category.Output format is "type1: word1; type2: word2". 
Option: Chemical 
Text: {0} 
Answer:
 None