Nuclear Radiation

Nuclear radiation refers to the emission of particles like photons during reactions that particularly include the nucleus of an atom. Nuclear radiation is also recognised as ionising radiation. The particles emitted by nuclear reactions can remove electrons from atoms and molecules and ionise them because they are suitably energetic.

What is Nuclear Radiation?

The energy released in the form of electromagnetic waves or high-speed charged particles is known as nuclear radiation. Radiation can come from many sources, both manufactured and natural. All living things are continually exposed to low doses of radiation from sunlight, rocks, and cosmic rays.

Nuclear radiation consists of an electromagnetic spectrum with its energetic portion, the x-rays and the gamma rays.

Types of Nuclear Radiation

There are three types of nuclear radiation:

• α-radiation
• Β-radiation
• γ-radiation

α-radiation

α -radiation has the greatest mass of all the three types, and it is the most energetic form of radioactive decay. α-particles are basically helium nuclei comprising two neutrons and two protons. They travel relatively slow because of their large mass (approximately 6% of the speed of light), but considerable ionisation has been produced by their high energy. This means that they do not penetrate far into the matter because they lose their energy over a small distance. Also, even a sheet of paper can block the radiation. Each time an α-particle ionises another molecule, it loses some of its energy.

β-radiation

Having a low mass, β-particles move at up to 98% of the speed of light; these are very fast-moving electrons. So, they have less energy as compared to the α-particles in spite of their high velocities. The nuclei that contain several neutrons to be stable emit β-particles. When a neutron changes into a proton and electron, these nuclei achieve lower energy or a stable state. The electron is instantly emitted from the nucleus as a β-particle.

γ-radiation

The electromagnetic radiation of very high frequency is known as γ-radiation. X-rays, visible rays, ultraviolet rays, infrared rays, radio waves and microwaves are also some other parts of the electromagnetic spectrum but not as intense as γ-radiation.

γ-rays have a wavelength ranging between 4 x 10^-10 and 5 x 10^-13 m.

The intensity of emitted electromagnetic radiation is inversely proportional to the distance from the source. So, basically, it is an inverse square relation:

I ∝ 1/d²

Measuring Radiation

An early unit used to measure amounts of radioactivity is the curie (Ci). Originally it was defined as the radiation emitted or released radium-226 of one gram.

But now, it is defined as one curie = 3.7 x 10¹⁰ radioactive decay per second.

SI Unit of radioactivity is curie, but it has been substituted by the becquerel (Bq).

1 radioactive decay per second = 2.703 x 10^-11 Ci = 1 becquerel

Nuclear Force

What is Nuclear Fuel?

Uranium is one of the most abundant elements on the earth and is full of energy. One fuel capsule of uranium produces energy equivalent to one ton of coal, approximately 149 gallons of oil. But before making it ready to go for the reactor, uranium is mined and processed to create nuclear fuel.

How is Nuclear Fuel Made?

Uranium must undergo four major processing steps (mining and milling, conversion, enrichment and fuel fabrication) before it goes into a reactor to convert it from its raw state to usable nuclear fuel.

• Firstly, the conventional methods are used for the mining process of uranium or by in-situ leach mining technique, where carbonated water is shot and piped up to the surface from the underground deposits. There is a diverse worldwide supply of uranium which primarily comes from countries like Canada, Kazakhstan, and Australia.
• To endure the chain reaction which is required to run a reactor, a high concentration of a specific isotope will be required by the uranium or uranium-235. Hence, to prepare it for enrichment, natural uranium is converted into several different forms. Special amenities enrich the uranium to make it usable for the nuclear reactor. The most important commercial fuel enrichment facilities are in countries like Germany, the United States, the Netherlands, the United Kingdom and Russia.

The enriched uranium is again transformed into a powder and then constrained into fuel capsules. The fuel fabricator loads these capsules into fuel assemblies which are sets of closed metal tubes, and these metal tubes are used in nuclear reactors.

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