26899
The purpose of this study was to review several in - process techniques for particle size determination ( Spatial Filtering Velocimetry , Focused Beam Reflectance Measurements , Photometric Stereo Imaging , and the Eyecon (R) technology ) and compare them to well - known and widespread off - line reference methods ( laser diffraction and sieve analysis ) .
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Please list all entity words in the text that fit the category.Output format is "type1: word1; type2: word2". 
Option: Chemical 
Text: {0} 
Answer:
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