5915
The purpose of this study was to investigate the effects of solid surface tensions , σsg − σsl , on the quality of printed lines , using 30–40 nm silver nanofluid ink .
 surface tensions, quality, silver, ink
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: manufacturing standard, machanical property, manufacturing process, material, engineering feature, process parameter, machine or equipment, application, process characterization, enabling technology, biomedical, concept or principle 
Text: {0} 
Answer:
 surface tensions, quality, silver, ink