☰ Contents · Physics

Nuclear physics in Uzbekistan

Lessons 45 · 1 lessons · N. Sh. Turdiyev, K. A. Tursunmetov, A. G. Ganiyev, K. T. Suyarov, J. E. Usarov, A. K. Avliyoqulov. Physics Grade 11, 1st edition. Niso Poligraf Publishing House, Tashkent, 2018
45

Nuclear-physics research in Uzbekistan and the use of its results in the economy

Textbook: pp. 182–185
GoalKnow the directions of nuclear-physics research in Uzbekistan and the practical uses of nuclear technology (medicine, agriculture, industry); do simple calculations about radiation dose and safety.
New words
Institute of Nuclear Physics · Yadro fizikasi institutiradioisotope · radioizotopdose (Sv) · doza (Sv)research reactor · tadqiqot reaktori
Explanation

Systematic nuclear-physics research in Uzbekistan began in the mid-20th century; in 1956 the Institute of Nuclear Physics was founded under the Academy of Sciences (near Tashkent, in the Ulugbek settlement). The institute works on nuclear structure and reactions, elementary particles and high-energy physics, radiation physics and materials science, and on producing isotopes with a research reactor. Practical uses: in medicine, radioisotopes for diagnosis and treatment (for example radiotherapy in cancer) and γ sterilisation of medical instruments; in agriculture, effects of radiation on seeds and plants, breeding and pest-control methods; in industry, flaw detection, measuring thickness and level, and changing material properties by irradiation; in analysis, activation methods. Note: work with radioisotopes is done only by trained, licensed specialists under dose control; neither at school nor at home may anyone approach them. The natural background dose is on average 2–3 mSv per year; the unit of equivalent dose is the sievert (Sv). Uzbekistan has announced plans to build its first nuclear power plant; as the project is in preparation, details may change and should be checked in official sources. Work on the Sun and astrophysics is also part of physics research.

Worked examples
The background dose is 2.4 mSv per year. In one day it is ≈ 2.4/365 ≈ 0.0066 mSv = 6.6 μSv. A chest X-ray has an approximate dose of 0.1 mSv, about 15 days of natural background, so it is done carefully and when necessary.
A sterilisation source uses an isotope with T ≈ 5 years (rounded for the exercise); initial activity 8000 TBq. In 15 years 3 half-lives pass: 8000/8 = 1000 TBq; therefore the source is replaced from time to time.
Class activity

In your notebook make two columns: applications of nuclear physics in medicine, agriculture and industry, and a matching safety rule for each (distance, time, shielding, expert supervision). Do not approach radioactive sources; this exercise is written only.

Practice
1
Name two uses of nuclear physics in medicine.
2
The background dose is 2 mSv per year. How many mSv in 10 years?
3
A source has T = 5 years and activity 800 TBq. How many TBq remain after 10 years?
4
Why do only trained specialists work with radioisotopes?