Complex sentence: In 1921 worked in Rabkrin, became Chief of Gold Dept of Soviet State Treasury the same year, worked in the management of Polytechnical Museum (1928) and became its director in 1930.
Split into simpler sentences: In 1921 worked in Rabkrin, he became Chief of the Gold Department of the Soviet State Treasury. He worked in management at the Polytechnical Museum starting in 1928 and became its director in 1930.