What is the titration invented by the Danish chemist famous for the concept of pH used for?
Sørensen formol titration The Sørensen formol titration(SFT) invented by S. P. L. Sørensen in 1907 is a titration of an amino acid with potassium hydroxide in the presence of formaldehyde. It is used in the determination of protein content in samples.
Xerography Xerography or electrophotography is a dry photocopying technique. Its fundamental principle was invented by Hungarian physicist Pál Selényi and based on Selényi's publications Chester Carlson applied for and was awarded U.S. Patent  on October 6, 1942. The technique was originally called electrophotography. It was later renamed xerography—from the Greek roots ξηρός "xeros", "dry" and -γραφία "-graphia", "writing"—to emphasize that, unlike reproduction techniques then in use such as cyanotype, this process used no liquid chemicals.