Wide-range optical pH imaging of cementitious materials exposed to chemically corrosive environments Autor Bernhard Müller, Cyrill Grengg, Viktor Schallert, Marlene Sakoparnig, Christoph Staudinger, Johanna Breininger, Florian Mittermayr, Birgit Ungerböck, Sergey M Borisov, Martin Dietzel, Torsten Mayr