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Here , we report in-situ characterization of melt-flow dynamics in every location of the entire melt pool in laser metal additive manufacturing by populous and uniformly dispersed micro-tracers through in-situ high-resolution synchrotron x-ray imaging .
 in-situ, melt-flow dynamics, melt pool, laser metal additive manufacturing, in-situ, high-resolution, x-ray imaging
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:
 in-situ, melt-flow dynamics, melt pool, laser metal additive manufacturing, in-situ, high-resolution, x-ray imaging