then a professor of physical and mathematical sciences. World War II Alexandrov became prominent during World War II, when he devised in collaboration with Igor Kurchatov a method of demagnetizing ships to protect them from German naval mines, known as the LPTI system. On 9 August 1941, Alexandrov and Kurchatov arrived in Sevastopol to organize work on equipping the Black Sea Fleet ships with the system, and by the end of October it had been installed on more than 50 ships. At the same time, Alexandrov and Kurchatov continued research to improve it. The method was effective by the end of 1941 and was in active use through the end of the war and afterwards. It was successfully used by the Soviet Navy, during the Siege of Sevastopol, Siege of Leningrad, on the Volga River during the Battle of Stalingrad and in the Baltic Sea campaigns. Later career Both Alexandrov and Kurchatov worked at the Ioffe Institute by that time (their laboratory separated from the Ioffe Institute and moved to Moscow in 1943 for the work on the Soviet atomic bomb project). From 1946 to 1955, he was director of the Institute for Physical Problems, where he was appointed to replace Pyotr Kapitsa. In 1955, he became deputy director of the Institute of Atomic Energy, and after the death of Kurchatov in 1960, he became its director. On the initiative of Alexandov, power plants for the nuclear icebreakers Lenin, Arktika, and Sibir were developed. Alexandrov was a member of the Communist Party of the Soviet Union from 1962. It was under the leadership of Alexandrov, that technical, organizational and production problems were solved in an unprecedentedly short time during the construction of the USSR's first nuclear submarine with a nuclear propulsion system. As a result, in 1952-1972, Sevmash mastered the serial production of submarines with a nuclear propulsion system and became the largest nuclear submarine shipbuilding center in the USSR and the world. At Sevmash, 163 combat submarines were built. In the 1970s, the company produced Typhoon-class nuclear submarines, which entered into the Guinness Book of Records as the largest submarines in the world. In the 1960s, on the initiative of Alexandov, the largest helium liquefaction plant was built in the USSR . This provided a wide front for fundamental research in the physics of low temperatures, as well as on the technical use of superconductivity. He was the scientific