Transcript
Page 1: Injection of high-energy positrons ... - Radiation Chemistryylene results in the formation of positronium (Ps), the hydrogen-like bound state between a positron and an electron, in

Injection of high-energy positrons into liquidsand polymers such as water, toluene, and polyeth-ylene results in the formation of positronium (Ps),the hydrogen-like bound state between a positronand an electron, in certain amount. Ps can beregarded as an electrically neutral particle with ex-tremely small mass and is an interesting object forresearch in radiation chemistry. A scientific fielddealing exclusively with the formation and annihila-tion of Ps in condensed matter is called posi-tronium chemistry. In this paper positronium chem-istry studied in the author’s laboratory in the lastfew decades is reviewed. The peculiarities of Ps inliquid-phase chemical reactions and its formationprocess in polymers are highlighted. Applicationsof the unique properties of Ps to polymer characteri-zation are described.

Key words: positronium, liquid-phase reaction, poly-mer, positron spur, free volume

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Positronium Chemistry and Its Application to PolymerCharacterizationYoshinori KD76N6H=> (National Institute of Advanced Indus-trial Science and Technology)�305�8565 _ur²$ 1�1�1 ³´µ¶·a{|¸_urx¹º 5»´¸

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