Nikolay Dmitriyevich Zelinsky (; 6 February 1861 – 31 July 1953) was a Russian and Soviet chemist. Academician of the Academy of Sciences of the Soviet Union (1929). Zelinsky studied at the University of Odessa and at the universities of Leipzig and Göttingen in Germany. Zelinsky was one of the founders of theory on organic catalysis. He was the inventor of the first effective filtering activated charcoal gas mask in the world (1915). Life Nikolai Zelinsky was born on 25 January (6 February) 1861 in Tiraspol in a noble family. His father Dmitry Osipovich Zelinsky who came from hereditary Volyn nobles, died of rapidly developing consumption in 1863; two years later his mother died of the same disease. The orphaned boy was left in the care of his grandmother M.P. Vasilyeva and he spent his childhood in her village. At the age of ten, Nikolai Zelinsky entered the Tiraspol district school for two-year courses to prepare for entering the gymnasium. Having completed them ahead of schedule at the age of 11, he entered the second grade of Odessa Richelieu Gymnasium. After graduating from the gymnasium in 1880, Zelinsky entered the natural science department of the Physics and Mathematics Faculty of the Novorossiysk University, and graduated in 1884. He was given an appointment at the university and was sent to Germany. He did research for two years (1885-1887), first he worked in the laboratory of Johannes Wislicenus in Leipzig. Then he performed a study of a new reaction in the laboratory of Viktor Meyer in Göttingen, which led to severe poisoning himself with mustard gas, which had not been studied enough by that time. In 1887 he was appointed Privatdozent in the Department of Chemistry at the Novorossiysk University. In 1888 he passed the master's exam, in 1889 he defended his Masters Thesis ("On the issue of Isomer in the thiophene series"), and in 1891 he defended his Doctoral Thesis ("Investigation of the phenomena of isomerism in the series of limiting carbon compounds"). He was invited to Moscow University on the initiative of Dmitri Mendeleev. He was a professor at Moscow University from 1893 until his death, with the exception of the period 1911-1917. Since 1893 he became an extraordinary professor at the Department of Organic Chemistry, since 1902 he was an ordinary professor. In 1911, he left the university with a group of scientists in protest against the policy of