41. In 1927, he studied ionisation in gases and published an important book, " Chemistry of the Electron ". 42. [" Ionisation " ] is built on a most sensitive handling and contrast of different kinds of percussive sounds. 43. All I can think is that I was getting mixed up with 54.4, the second ionisation energy of helium. 44. This level of ionisation cannot be achieved by an O6 star, so will be almost entirely due to the WR component. 45. With decreasing energy the wall effect gives way to a combination of wall effect and direct ionisation , until direct gas ionisation dominates. 46. With decreasing energy the wall effect gives way to a combination of wall effect and direct ionisation, until direct gas ionisation dominates. 47. The spray is then ionised by extractive electrospray ionisation ( EESI ) and analysed using tandem mass spectrometry ( MS / MS ). 48. Treatment is by concentration of de-ionisation waste waters and disposal to landfill or by careful pH management of the released wastewater. 49. This was used to solve problems related to low temperature helium, and the photo-ionisation of oxygen in the upper atmosphere. 50. Much of the percussion music of George Crumb is particularly owing to such Var�se works as " Ionisation " and " Int�grales ".