Except TiO2 no other compounds containing elemental Ti can be identified.
It seems that TiO2 was inert and stable during the cement hydration
process because and the variation of TiO2 content was very small.
This finding confirms that the nano-TiO2 acted as a non-reactive
filler, ruling out the speculation that TiO2 may be of certain pozzolanic
activity [26].