This document discusses radioisotopes, their formation and applications. It provides examples of common radioisotopes like hydrogen-3, americium-241 and gold-198 and their half-lives. It also describes different types of radiation like alpha particles and beta rays. Applications of radioisotopes discussed include medical uses like cancer treatment and seed irradiation to kill harmful microorganisms. The document also briefly touches on cyclotrons used to produce medical radioisotopes and how radiation is used to change the color of gemstones.

1. FORMATION and APPLICATIONS

2.  Radioisotopes are radioactive isotopes of an
element. They can also be defined as atoms
that contain an unstable combination of
neutrons and protons, or excess energy in
their nucleus.

3.  Naturally
 All 0.7% of
naturally-occurring
uranium is
uranium-238
 Artificially

4. HYDROGEN-3
HALF LIFE- 12.32 YEARS
AMERICIUM-241
HALF LIFE- 432.5 YEARS

5. HALF LIFE-5.27 YEARS
GOLD-198
HALF LIFE-2.70 DAYS

6.  Atoms with an unstable nucleus regain
stability by shedding excess particles and
energy in the form of radiation. The process
of shedding the radiation is called radioactive
decay.

8.  β-Rays are fast moving electrons.
 Their speed ranges from 1% to 99% of speed
of light.
 They are more penetrating than α-particles.
32
15P →
32
16S1+
+ e−

9.  1. Cyclotron ( circular accelator).
 Cyclotrons are best-suited to producing
proton-rich radioisotopes, such as fluorine-
18.

13. POPULATION OF INDIA (2019)- 1,369 millions in 2018,

15. Untreated seed with micro-
organisms on seed skin.
Untreated seed with micro-
organisms
on seed skin.

16. Electron accelerator targeted on flow of
seeds.

17. - To destroy the harmful micro-organisms completely.

19.  Primary brain tumors occur in around
250,000 PEOPLE A YEAR globally.
 Due to increase in exposure to high doses of
IONIZING RADIATION and a family history of
brain cancer.
TUMOR

20. CANCER CELLS

21.  IMRT ( INTENSITY MODULATED RADIATION
THERAPY ).
 RADIATION can be used to KILL CANCER.
 Machine used – LINAC.

22. 1. 2.

23. COLLIMATOR

25.  The process in which a GEMSTONE is
ARTIFICIALLY irradiated in order to enhance
its OPTICAL PROPERTITIES.
 That is, to CHANGE THE COLOR OF
GEMSTONES.

26.  Colour centre is DEFECT in Crystal structure.
 These are introduced by extreme heat
exiciting OR by bombardment with
natural/man-made radiation.
 Color centres absorb radiation/light of
specific wavelengths and displays color
complementary to it.

27. γ-RAYS

28. ENERGY ABSORBED

30.  MOBILE MACHINE-FOR ELECTRON SEED
TREATMENT.

31.  NAARRI ( Navi Mumbai):
◦ https://www.naarri.com/images/day%2002/IT23%20F
%20H%20Roegner%20-
%20Electron%20Treatment%20of%20Seed-min.pdf
ANSTO ( AUSTRALIA):
https://www.ansto.gov.au/education/nuclear-
facts/what-are-radioisotopes#content-radioisotopes
WIKIPEDIA:
https://en.wikipedia.org/wiki/Gemstone_irradiation
YOUTUBE:
https://www.youtube.com/watch?v=_moypMx05Fw