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10MW ( 10x10 or 10 million watts ). ITER is the world ’ s largest fusion experiment ; it is hoped it will be capable of producing 500MWe of fusion power but this is still an experimental rather than commercial facility .
Half-life : The time required for one-half of the atomic nuclei of a radioactive sample to decay .
Watt : Unit of energy equivalent to 1 Joule per second . It describes the rate of energy transfer and is named after James Watt .
Current Fusion Developments Fusion experiments are being conducted at ITER in France and at the Culham Centre for Fusion Energy ( CCFE ) near Oxford . They use extreme magnetic fields to confine plasma into a ring and heat it until fusion occurs . The temperatures in JET at Culham can reach 100 million degrees , many times hotter than the Sun ’ s core .
What is a Plasma ? Plasma is one of the four fundamental states of matter : liquid , solid , gas and plasma . Plasmas are usually created by heating a gas until the electrons become detached from their parent atom or molecule . A plasma is a partiallyionized gas , containing ions , electrons and neutral atoms . The properties of plasma are very different to those of a normal gas . For example , a plasma is electrically conductive ; its motion can be influenced by electric and magnetic fields .
Everyday examples of plasmas include plasma columns in neon tubes , electric sparks and the plasma filament in a lightning flash .
Errata ( Back to Basics , Launch Issue ) p35 , column 1 , purple table , bottom line , right column should read
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“ EBq ( Exa ) = 10 Bq ” p35 , column 2 , para 2 ( to right of text box with blue border ), change “ Tellurium-131 ” to “ Tellurium-131m ” p35 , column 2 , blue table , line 3 , correct spelling of “ Phosphorus ”
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36 Radiation Protection Today www . srp-rpt . uk