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Discover the history, effects, and applications of atomic radiation in a simplified manner. Explore natural and man-made sources, biological effects, and radiation protection. Learn about radiation's role in medicine, power, agriculture, and industry.
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The Secrets of Atomic Radiation by Dr. Mohammad Al-Jarallah Professor, Department of Physics King Fahd University of Petroleum & Minerals Dhahran, Saudi Arabia http://faculty.kfupm.edu.sa/PHYS/mibrahim
Abstract • Atomic radiation as a phenomenon is as old as the universe itself. It is a normal part of nature and life. At this very moment, thousands of rays are penetrating your body every second. The majority of radiation originates in nature and is totally independent of what man does. Today, our environment also contains a small amount of extra “unnatural” radiation which is caused by the activities of mankind. • The use of radiation has become an integral part of modern life. From the x-ray picture of broken limb to the treatment of cancer, the medical applications of radiation are now accepted as commonplace, and x-ray facilities are available in almost every community hospital. • Radiation contributes in the production of electricity, agriculture, and in other industry. • In my lecture I will try to describe in simple terms, what ionizing radiation to which man is exposed and second to review its sources and then I will shed a light on the applications of radiation in different walks of life. The Secrets of Atomic Radiation Hadeed
The Secrets of Atomic Radiation • The Atom • Atomic Radiation • Our Radiation Heritage • Man Made Radiation • Application of Atomic Radiation In: • Medicine • Power Production • Weapons • Agriculture • Industry • Biological Effects of Radiation • Radiation Protection • Summary The Secrets of Atomic Radiation Hadeed
1 - The Atom • Radiation cannot be understood without knowing a little about the structure of the atom, since ultimately all radiation originates inside the atom. The atom resembles a miniature solar system. In the center of the atom is the nucleus, while electrons orbit around it, rather as planets more around the sun. • The nucleus contain almost all of the weight and substance of the atom; it is build up of protons, which are about the same size as a proton but do not carry an electric charge. • The electrons in orbit are tiny particles, nearly 2000 times smaller than a proton or a neutron. The inside of the atom is almost all unoccupied space!. The analogy with the solar system? The Secrets of Atomic Radiation Hadeed
The Elements • The Isotopes • Molecules The Secrets of Atomic Radiation Hadeed
2 - Atomic Radiation • Definition of Atomic Radiation: It is that radiation which has the capability of ionizing atoms and molecules, and so cause changes which are biologically important. • Types of Atomic Radiation: The main are The Secrets of Atomic Radiation Hadeed
1. - Rays The Secrets of Atomic Radiation Hadeed
2. - Rays The Secrets of Atomic Radiation Hadeed
3. - Rays The Secrets of Atomic Radiation Hadeed
4. X - Rays The Secrets of Atomic Radiation Hadeed
3 - Our Radiation Heritage • We can classify natural atomic radiation that we are exposed to either in terms of their sources or their locations in the environment. • The Sources of Natural Atomic Radiation are: • Cosmic Radiation • Cosmogenic Radiation • Naturally Radioactive Series • Singly occurring Primordial Radionuclies • Radioactive Ores and By-products (TENORM) • Radon and Its Progeny The Secrets of Atomic Radiation Hadeed
A. Cosmic Radiation - Source: Outer Space 1- Primary Cosmic Radiation: - 87 % protons -11 % alpha particles - 2% heavier nuclei & electrons 2- Secondary Cosmic Radiation: - pions, meuons, electrons, photons, protons & neutrons The Secrets of Atomic Radiation Hadeed
B. Radioactivity of the Earth - Mainly ( U-238 series, Th-232 series, K-40 (abundance 0.01% ) ) - In 1 km3 there is about: 1 ton K-40 T 1/2 = 1.28 X 109 yr 4 tons U-238 T 1/2 = 4.47 X 109 yr 8 tons Th-232 T 1/2 =14.1X 109 yr Rb-87T1/2 =50X 109 yr The Secrets of Atomic Radiation Hadeed
C. Radioactivity of Air • Radon & its daughters ( Lung Dose ) • - C-14 (1 in 1012 ) T 1/2 = 5730 yr • - H-3 T 1/2 = 12.3 yr • - Na-22 T 1/2 = 12.6 yr • - Be-7 T 1/2 = 53.3 days The Secrets of Atomic Radiation Hadeed
Decay Series of Uranium-238 238U 234Th234Pa234U Alpha Decay (4He) Beta Decay (e) 230Th 226Ra 222Rn 218Po 214Pb214Bi214Po 218P b 210Bi 210Po 206Pb The Secrets of Atomic Radiation Hadeed
D. Radioactivity of Water -Sea water : K-40 -Spring water :U, Th, Ra E. Radioactivity of the Human Body - Comes from food & water consumption - In the body: K-40, Rb-87, Ra-226, U-238, Po-210 & C-14 - In the Skeleton: Ra-226 - In Bone: U-238 & Po-210 The Secrets of Atomic Radiation Hadeed
4- Man Made Radiation SourcesList of Major Man-Made Radiation Sources - Nuclear Particle Accelerators. - Nuclear Reactors. - Isotopic Neutron Sources. - Medical Syringe & Food Sterilization by Radiation. - Electron Beam. The Secrets of Atomic Radiation Hadeed
A.Fallout - Debris which settles to the earth as a result of a nuclear blast. - 1 Megatons device can activate up to 50000 tons of debris. - These are more than 200 fission products. - Examples: Sr-90 T 1/2 = 28.1 yr Cs-137 T 1/2 = 30 yr I-131 T 1/2 = 8.06 days C-14 T 1/2 = 5730 yr H-3 T 1/2 = 12.3 yr The Secrets of Atomic Radiation Hadeed
B. Consumer Products & Miscellaneous Sources - Wrist Watches & Alarm Clocks: Ra-226, H-3. - Tobacco Products: Pb-210, Po-210. - Building Materials: U, Th, K-40. - Combustion of Fuels: Ra-226, Th-232, C-14, K-40, U, …. - Smoke Detectors: Am-241. The Secrets of Atomic Radiation Hadeed
Consumer Products & Miscellaneous Sources - Porcelain used for making dentures: K-40 doped with U. - Some rose tinted eyeglasses contain up to 0.25 % Th. - Airport Luggage Inspection System uses X-rays. - Television Sets: give soft X-rays. The Secrets of Atomic Radiation Hadeed
5 - Application of Atomic Radiation A. Medicine 1- Radiation Therapy - In the bast: Co-60 - Now: Linear Acceleration up to 23 MeV The Secrets of Atomic Radiation Hadeed
2- Radiology 3- Nuclear Medicine - I-131, Tc-99m, P-32, Fe-52 The Secrets of Atomic Radiation Hadeed
B. Power Production Radioisotope thermoelectric generator (1000 TBq 90Sr) The Secrets of Atomic Radiation Hadeed
Food irradiator 400 000 TBq 60Co C. Agriculture The Secrets of Atomic Radiation Hadeed
D. Weapons The Secrets of Atomic Radiation Hadeed
E. Industrial Application • Thickness Gauges:for paper, plastic sheets, tires, pipe, • steel, etc. . • - Moisture Gauges:for soil, coke, steel making plant. • - Density Gauges:for soil compactor, steel making plant. • - Level Gauges:water & oil reservoirs. • - Radiography:oil pipes in refinery, airoplanes • - Mineral Exploration:in oil & mineral exploration. The Secrets of Atomic Radiation Hadeed
Moisture-Density Gauges The Secrets of Atomic Radiation Hadeed
6 - Biological Effects of Radiation How Radiation can Lead to Damage in Tissue Radiation Electrical Effect (Ionization) Physical & Chemical Changes Damage to DNA Cell Death Cell Transformation EarlyEffect Hereditary Defects Cancer The Secrets of Atomic Radiation Hadeed
7 - Radiation Protection The three principles of radiation protection: • Distance • Time • Shielding The Secrets of Atomic Radiation Hadeed
8 - Summary Atomic radiation as a phenomenon is as old as the universe itself. It is a normal part of nature and life. At this very moment, thousands of rays are penetrating your body every second. The majority of radiation originates in nature and is totally independent of what man does. Today, our environment also contains a small amount of extra “unnatural” radiation which is caused by the activities of mankind. The Secrets of Atomic Radiation Hadeed
Thank you The Secrets of Atomic Radiation Hadeed