electrons,fast 《英文msh詞典》Electrons,Fast ; [入口詞] Electrons,Fast ; [主題詞] Electrons ; [英文釋義] Stable elementary particles having the smallest known negative charge,present in all elements; also called negatrons. Positively charged electrons are called positrons. The numbers,energies and arrangement of electrons around atomic nuclei determine the chemical identities of elements. Beams of electrons are called CATHODE RAYS or BETA RAYS,the latter being a high-energy biproduct of nuclear decay.