Nikolai N. Semenov was a physical chemist and physicist who was the first Soviet citizen living in Russia to win the Nobel Prize. His scientific work focused on chain reactions and their characteristic "explosiveness" during chemical transformations. This influenced the development of greater efficiency in automobile engines and other industrial applications where controlled combustion was involved, such as jet and rocket engines. Enjoying important academic success, he also played a significant role as a spokesperson for the Soviet scientific community. He was instrumental in establishing institutions where physical chemistry could be studied, and he collaborated in creating a journal dedicated to the field. In addition, he actively participated in scientific conferences dealing with physical chemistry.
Nikolai Nikolaevich Semenov was born on April 16, 1896, in Saratov, Russia, to Nikolai Alex and Elena (Dmitrieva) Semenov. He graduated from Petrograd University (later renamed Leningrad; now called St. Petersburg, its original name) in 1917, the year of revolution that led to the establishment of Communism in Russia. Semenov had shown an interest in science from the time he entered Petrograd University at age sixteen in 1913 to study physics and mathematics. He published his first paper at the age of twenty on the subject of the collision of molecules and electrons. After graduation from Petrograd, Semenov accepted a post in physics at the Siberian University of Tomsk, but in 1920, he returned to Petrograd where he was associated with the Leningrad Institute of Physics and Technology for eleven years. In 1928, Semenov organized the mathematics and physics departments at the Leningrad Polytechnical Institute. He became the head of the Institute of Physical Chemistry of the Soviet Academy of Sciences in 1931, where he remained for more than thirty years. In 1944, Semenov became the head of the department of chemical kinematics at the University of Moscow.
The branch of physical chemistry concerned with the rates and conditions of chemical processes, called chemical kinetics , dominated Semenov's research from his earliest studies. His work led to the understanding of the sequence of chemical reactions and provided insight into the conversion of substances into products. Along with some of his colleagues, Semenov felt that physics held the key to understanding chemical transformations. The branch of science referred to as chemical balances was a consequence of their work.
Semenov was awarded the Nobel Prize in chemistry in 1956 with English chemist Cyril Hinshelwood for their researches into the mechanism of chemical reactions. Both scientists had worked independently for twenty-five years on chemical chain reactions and their importance in explosions. There is wide agreement in the scientific community that Semenov and Hinshelwood were responsible for the development of plastics and the improvement of the automobile engine. There remains some controversy over whether their work on chain reactions contributed to atomic research.
Other experiments by Semenov had culminated in his theory of thermal explosions of mixtures of gases. As a result of this research, he increased the understanding of free radicals --highly unstable atoms that contain a single, unpaired electron. Semenov demonstrated that when molecules disintegrate, energy-rich free radicals are formed. His extensive works on this subject were published first in Russian in the 1930s and later in English.
In subsequent research, Semenov found that the walls of an exploding chamber can influence a chain reaction as well as the substances within the chamber. This concept was particularly beneficial in the development of the combustion engine in automobiles. Semenov's chemical chain reaction theory and his observations on the inflammable nature of gases informed the study of how flames spread, and had practical applications in the oil and chemical industries, in the process of combustion in jet and diesel engines, and in controlling explosions in mines. This work was based on Semenov's earlier investigations of condensation of steam on hard surfaces and its reaction under electric shock.
Semenov made substantial contributions to the development of Soviet scientific institutions and journals. He was active in the training of Soviet scientists and the organizing of important institutions for scientific research in physical chemistry. His long association with the Academy of Sciences of the U.S.S.R. earned him an appointment as a full member in 1932. When the Academy moved to Moscow in 1944, Semenov began teaching at Moscow University. Semenov's theories of combustion, explosion, and problems of chemical kinetics, along with a bibliography of his work by the Academy, were published during the 1940s and 1950s and helped secure his role in his field.
Semenov was not immune to the politics of his country. He became a member of the Communist Party in 1947, and he was the person who answered criticism of the Soviet Union from the Bulletin of the Atomic Scientists, a publication of the United States. The Bulletin challenged Soviet scientists to protest against Soviet restrictions on release of scientific publications from the country. Semenov replied that there were no such restrictions and accused the American scientists of ignoring their own government restrictions. It was discovered later that some Soviet publications had been arriving regularly at the Library of Congress in Washington, D.C.
In his own country, Semenov was highly regarded. He had received the Stalin Prize, the Order of the Red Banner of Labor, and the Order of Lenin, the latter seven times. He served his country in the political capacity of deputy in the Supreme Soviet in the years 1958, 1962, and 1966, and he was made an alternate to the Central Committee of the Communist Party in 1961. While he was a loyal Soviet citizen, he did work diligently for freedom in scientific experimentation.
On September 15, 1924, he married Natalia Nikolaevna Burtseva, who taught voice, and they had a son, Yurii Nikolaevich, and a daughter, Ludmilla Nikolaevna. Semenov enjoyed hunting, gardening, and architecture in his leisure time. He died in 1986.
This is the complete article, containing 957 words
(approx. 3 pages at 300 words per page).
