Nuclear Radiation

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Nuclear Radiation
http//www.alternate-energy-sources.com/nuclear-ra
diation.html

• Amanda, Kartik, Adaobi,
• Ifeoma, and Isabelle
• Period 6
• 11/14/07

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Nuclear Radiation

• Nuclear Radiation is ionizing radiation
  originating from the nucleus due to radioactive
  decay or nuclear reactions .

Isabelle
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What is ?
Radioactivity

• The spontaneous emission of particles and/or
  energy from atomic nuclei.
• Radiation is measured in REMs.

Amanda
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Radioactive Elements

• Key radioactive element Radon- produced by
  decaying uranium it seeps through cracks of
  poorly ventilated buildings
• All of the elements after and including
  84(Polonium) are radioactive.
• Theyre radioactive because of a lack of balance
  between the numbers of neutrons and protons.
• Some elements are only radioactive sometimes.
• Those elements are Carbon, Potassium, Cadmium,
  and Bismuth.

Isabelle and Ifeoma
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Nuclear Radiation and Materials

• Nuclear Radiation can be both extremely
  beneficial and extremely dangerous. Nuclear
  materials substances that emit nuclear
  radiation are fairly common and have found their
  way into our normal vocabularies.
• Radioactive materials are defined as any material
  which has specific activity greater then 0.002
  micro curies per gram. This definition does not
  specify quantity, only concentration.

Amanda
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The History of Nuclear Radiation

• It was discovered by Henri Becquerel.
• He was experimenting with uranyl sulfate on
  photographic plates when he noticed that uranium
  crystals had formed.
• About a week later the crystals began to emit
  clear and strong images on the photographs,
  without sunlight.
• This meant that uranium could emit radiation
  without an external energy source...thus leading
  to the discovery of radioactivity.

Amanda
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Types of Nuclear Radiation

• Ionizing Radiation
• Alpha particles-large and slow
• Beta particles-Fast and produced in nuclear
  reactions aka positrons
• Gamma-high energy causes radioactive emission
  small

Isabelle
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Nuclear Decay

• Alpha Decay
• The emission of the alpha particle from the
  nucleus (Helium particle)
• Beta Decay
• The emission of the electron from the nucleus
  gives off light
• Gamma Decay
• emits gamma rays has
• no effect on nucleus, no
• atomic mass, or number

Ifeoma
http//molaire1.club.fr/e-rays.JPG
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Half-Life

• The half-life of an element is the amount of time
  it takes for half of the atoms in any given
  quantity of a radioactive isotope to decay.
• Example Uranium 238 has a half-life of 4.5
  billion years. This means that in 4.5 billion
  years, half of the atoms of Uranium 238 will have
  decayed. In another 4.5 billion years, the half
  of remaining atoms will once again split in half.
• A practical use of half-life is in modern
  medicine.

Ifeoma
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Biological Effects

• High doses of more than 100 Gy affect the central
  nervous system, resulting in loss of
  coordination, and breathing
• Doses from 9 to 10 Gy damage the gastrointestinal
  tract, causing nausea, vomiting, diarrhea and
  dehydration
• Lower doses from 3 to 9 Gy damage the bone
  marrow. This leads to loss of appetite and hair,
  hemorrhaging, inflammation, and secondary
  infections such as pneumonia.

Adaobi Agugo
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Human Effects

- People at Work Fuel cycle Industrial
radiography Radiology departments (medical)
Radiation oncology departments Nuclear power
plants Nuclear medicine departments National
(government) and university research laboratories
-People in the Public (Man-Made) Tobacco
Televisions Medical x-rays
Smoke detectors Lantern mantles
Nuclear medicine Building materials
Adaobi Agugo
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Adaobi Agugo
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Geiger Counter

• The Geiger counter first developed by Hans Geiger
  in 1908.
• Geiger constructed the earliest form of his
  radiation counter in 1908.

Kartik J
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Radiation Smoke Detector

• George Darby first invented the radiation smoke
  detector 1902.

In the early days the smoke detector worked when
the heat of the room became overwhelming and
dangerous, the butter would melt, causing the two
circuits to collapse onto one another, initiating
the alarm.
Kartik J
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How to measure Nuclear radiation

• REM - Radiation Equivalent Man
• RAD - Radiation Absorbed Dose (radiation that
  deposits energy at 1.00 x 10-2 J per kilogram)
• Curie - radioactivity of radioactive material
• 1 Curie 3.7 x 1010 disintegration/sec
• Becquerel - 1 disintegration/second
• Gray - 1 gy 100 rad
• Sievert - 1 sv dose (rad) x quality factor

Isabelle and Ifeoma
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Real Life Nuclear Radiation

• Kosovo, Serbia- caused by left
• over USSR nuclear projects from
• the Cold War.
• Hiroshima and Nagasaki, Japan-
• caused by atomic bombs
• dropped by the US in 1945 to
• end WWII.
• Australia- caused by nuclear
• tests conducted in the 1950s.
• Cherynobyl, Russia- caused
• by nuclear meltdown.

Chernobyl, Russia
Isabelle
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Interesting Facts
Location of worlds most abundant uranium reserves

• 435 nuclear power plants generate electricity in
  30 countries in the world.
• 4,000 cases of thyroid cancer were reported by
  children who drank milk from cows that consumed
  nuclear contaminated grass in Chernobyl.
• Radiation can lead to light effects such as
  reddening of the skin, or grave effects, such as
  cancer or early death.
• 80 of radiation comes from nature like soil or
  sunlight.

http//www.coolschool.ca/lor/PH11/unit9/U09L04.htm
Isabelle
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Pictures
Kartik J