4550
Annealing of MnO @ SiO ( 2 ) nanospheres in a reducing gas environment resulted in the transformation of the core - shell structure into a hollow structure as a result of outward diffusion of MnO species into the thermodynamically more stable silicate phase .
 Chemical: MnO; Chemical: SiO ( 2 ); Chemical: MnO; Chemical: silicate
Please list all entity words in the text that fit the category.Output format is "type1: word1; type2: word2". 
Option: Chemical 
Text: {0} 
Answer:
 Chemical: MnO; Chemical: SiO ( 2 ); Chemical: MnO; Chemical: silicate