This image was acquired from
wikimedia. It was marked as Public Domain or CC0 and is free to use. To verify, go to the source and check the information there.
Keywords from Image Description:
Nanomaterials Concrete . The barely visible bluegreen area at the top of this Xray image of concrete with the NIST nanoadditive shows that very few chloride ions in green penetrate into the concrete Credit NIST Disclaimer Any mention of commercial products within NIST web pages is for information only it does not imply recommendation