Roentgen (unit) absorbed dose in a wide range of matter. When measuring absorbed dose in a human due to external exposure, the SI unit the gray, or the related non-SI rad are used. From these can be developed the dose equivalents to consider biological effects from differing radiation types and target materials. These are equivalent dose, and effective dose for which the SI unit sievert or the non-SI rem are used. The following table shows radiation quantities in SI and non-SI units: Roentgen (unit) The roentgen or röntgen () (symbol R) is a legacy unit of measurement for the exposure of X-rays
Wilhelm Stier - 1999, Professor at the Techical University of Graz, Austria Wilhelm Stier - Familytree - Family member. Wilhelm Stier Wilhelm Stier (born May 8, 1799 in Błonie near Warsaw, died September 19, 1856 in Schöneberg, full name: Friedrich Ludwig Wilhelm Stier) was a German architect and university teacher at the Berlin Bauakademie. Wilhelm Stier was born the son of Christiane Eleonora Stiers 1766 - & Friedrich Ludewik Stier 1765 - 1815 a German postmaster & taxman in the then Prussian province of South Prussia & then Wilhelms family moved to Silesia. Wilhelm Stier was Grand son to Medical Officer /