Nuclear Power

Three Mile Island, Harrisburg, PA

Limerick Power Plant,Boyertown, PA

Cooling Tower Clip

Nuclear Fission

CHAIN REACTION DEMO

Can Power Plants Explode?

• Bomb-grade = highly-enriched(~85-90% U-235) • Nuclear Power Plant = only 3-5% U-235

Uranium Oxide Uranium Uranium dioxide (yellow cake) Hexafluoride (pellets)

Nuclear Fusion

approximately 40 million Kelvins

Nuclear reaction in which two light nuclei combine to form a heavier nuclei.

This takes place in stars and allows them to burn.

Nuclear Waste

WIPP Clip

Waste Clip #2

Worldwide Nuclear Power Reactors

World Nuclear Power Plants

Nuclear Problems and Solutions

• Three Mile Island 1979– 50% core meltdown, stuck valve with no indicator, which

released water, but containment vessel held– More sensors added, better communication to experts in

Washington, don’t turn off emergency cooling• Chernobyl 1986

– turned off cooling system– Poor steam cooling reactor design allowed unstable steam

pocket to explode– Graphite caught fire– Design not used in other countries

RADON

PHYSICAL CHARACTERISTICS OF RADON

- an odorless, tasteless, invisible gas that mixes with air.- chemically inert and essentially non-reactive.

Worried?

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Radiation Measurement

A Geiger-Müller counter• detects the intensity of radiation• uses ions produced by radiation to

create an electrical current.

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Detecting Radiation

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Some Radioisotopes Used in Nuclear Medicine

PET SCAN

PET vs. CAT

Source Dose (mrem)

Chest X-ray 10

5-hour plane flight 3

Live within 50 miles of coal-fired power plant for 1 year

.03

Live within 50 miles of a nuclear plant for 1 year

.009

US Average Annual Whole Body Radiation Dose

360

Radiation Dose Comparisons

Chemistry in Context, Chapter 7http://www.who.int/ionizing_radiation/env/cosmic/en/index1.html

Effect of Smoking on Radiation Dose•If you smoke, add about 280 mrem

(source does not specify # packs per day smoked)

• Tobacco contains Pb-210, which decays to Po-210.• Pb-210 deposits in bones.• Po-210 in liver, spleen, and kidneys

http://www.doh.wa.gov/ehp/rp/factsheets/factsheets-htm/fs10bkvsman.htm

http://web.princeton.edu/sites/ehs/osradtraining/backgroundradiation/background.htm

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Learning Check

Which of the following radioisotopes are most likely to be used in nuclear medicine?

1) 40K half-life 1.3 x 109 years2) 42K half-life 12 hours3) 131I half-life 8 days