Images Dated 21st November 2003

open-uri20120929-19261-xjqqmu

2005 Dunlop MSA British Touring Car Championship
Brands Hatch, England
1st - 2nd October 2005
Yvan Muller (VX RAcing Vauxhall Astra Sport Hatch) crashes after contact with Jason Plato (SEAT Sport UK SEAT Toledo Cupra). Action.
World Copyright: Jeff Bloxham/LAT Photographic
ref: Digital Image Only

Different coloured Light Emitting Diodes (LEDs)

Blue diode. View of a hand holding the worlds first marketed blue light emitting diode (LED) made from gallium nitride. It is shown with different coloured LEDs. The only blue LEDs available before this were based on silicon carbide. These were very inefficient and did not glow very brightly. LEDs are made of two thin film layers that contain specific impurities which give them opposite electrical properties. An electric current passing through the LED will make it produce light. LEDs were developed in the 1960s but could initially only produce red or green light. In 1995 the Nichia corporation of Japan first marketed these blue LEDs

© VOLKER STEGER/SCIENCE PHOTO LIBRARY

Chemical weights

Assorted chemical weights. The different amount of each chemical represents a measurement known as the mole. One mole of any sample contains the same number of molecules or atoms. The weight (shown in grams) of each molar sample is determined by the weight of the molecules (the molecular weight) and is calculated from the weights of the atoms in the molecule. Three of the chemicals are hydrated with water (H2O). The chemical formulae are, clockwise from lower left: NaCl, FeCl3.6(H2O), CuSO4.5(H2O), KI, Co(NO3)2.6(H2O) and KMnO4. The heaviest atom here is iodine (I), 8 times heavier than oxygen (O). The transition metal compounds are coloured

© ANDREW LAMBERT PHOTOGRAPHY/SCIENCE PHOTO LIBRARY