Semenov, Nikolai

SEMENOV, NIKOLAI N. (1896-1986). A Russian chemist and physicist who won the Nobel Prize in 1956. He authored books on the chain reaction and problems of chemical kinetics and reactivity, as well as many articles. His work concerning thermal combustion and explosion is utilized in rockets and jet engines. He received his doctorate at Leningrad State University. 

On October 1, 2005, we commemorated the 90th anniversary since the birthday of Nikolai Markovich. The Russian Academy of Sciences, the Department of Chemistry and Science of Materials, the Emanuel Institute of Biochemical Physics, the Semenov Institute of Chemical Physics, the Institute of Problems of Chemical Physics (Chemogolovka, Moscow Region), and the Faculty of Chemistry of Lomonosov Moscow State University commemorated the date and held a conference dedicated to the memory of Academician Emanuel. The title of the Conference, Scientific Ideas of Academician N.M. Emanuel and Modern Science, is significant because Nikolai Markovich put forward many scientific ideas and hypotheses, which were developed later in modem science. 

As a branch of science, chemical physics was established in the first three decades of the 20th century by some famous scientists (including the Nobel Prize Laureate, Academician Nikolai N. Semenov - the founder of the Institute of Chemical Physics, Academy of Sciences of the USSR). Biochemical physics, on the other hand, representing the area of knowledge at the junction of three natural sciences, was created in the middle of the 20th century. The leader of this creation was Academician N.M. Emanuel - the founder of the Institute of Biochemical Physics, Russian Academy of Sciences. 

This challenge was met by Russian chemist Nikolai Nikolaevich Semenov (1896-1986), working in St. Petersburg, and, independently, English chemist Cyril Norman Hinshelwood (1897-1967) at Oxford. In 1928 they each developed the concept of a branched chain reaction to account for the kinetics of these explosions and their strange dependence on pressure and temperature. 

We will remind the reader that solid bodies (in particular polymers) are not intrinsically flammable This has been established since 1920-1930 by scientists of the school of the Nobel Prize laureate, professor Nikolai Semenov and the architects of the Soviet nuclear bomb. Professors Yuli B. Khariton and Jacob B. Zel dovich. However, the gaseous products of polymer pyrolysis do bum. Hence, the lower is the speed of pyrolysis, the less is the polymer combustibility. The pyrolysis of polymers is the first and most important stage of combustion. 

In the early 1930s, Polanyi visited the Soviet Union and became friends with Soviet chemists, especially with Alexander Frumkin and Nikolai N. Semyenov (Semenoff, Semyonov, Semenov). Both of them were members of the Editorial Board of Acta Physicochimica URSS. Besides Semyenov (Nobel prize in chemistry, 1956) and Frumkin, some outstanding scientists hallmarked this journal, such as J. Frenkel and N. Kumakov, and later P. Rehbinder and M. Temkin (Tyemkin) (Fig. 12.16). Polanyi published several papers also in other Soviet scientific journals such as in Uspekhi Khimii and Phys. Z. Sowjetunion in 1932 and 1933. Acta Physicochimica URSS published by the Academy of Sciences of the USSR was an excellent foreign-language journal (cost 4/volume), and Polanyi certainly... 

The Nobel Prize was not awarded for the discovery of chain reactions. However, in 1956, Sir Cyril Norman Hinshelwood from Great Britain (1897-1987, London) and Nikolai Nikolaevich Semenov from Russia (1896, Saratov, to Moscow, 1986) were jointly awarded the Nobel Prize for (mostly) developing branched chain reactions. The first monograph on chain reactions was written by Semenov. 

Ihe Nobel Prize which is ik)w to be given to Sir Cyril Norman Hirrshelwood and Academician Nikolai Nikolaevich Semenov for... 

Sir Cyril Norman Hinshelwood, Academician Nikolai Nikolaevich Semenov. More than half a century has elapsed since the first Nobel Prize in Chemistry was awarded to van t Hoff for his discovery of the laws of chemical dynamics. Some of the greatest advances in chemical kinetics since that time have emerged from your researches and they have inspired a great number of scientists to continued fruitful studies. Your results are of equally great importance to technology and to the more theoretical aspects of chemistry. 

Figure 12.14. Nikolai Semenov (1896-1986) won the Nobel Prize for chemistry in 1956...

---