正电子发射层析 zhèngdiànzǐfāshècéngxī PET scan Definitions Defs Origin Strokes Stroke Words Sentences Sents 正电子 正電子 zhèngdiànzǐ positron positron; antielectron; the antiparticle of the electron that carries a positive charge发射 發射 fāshè to transmit to emit or transmit signals, radio waves, or particles层 層 céng noun layer A physical sheet, thickness of material, or stratum covering a surface析 xī verbnoun to analyze (bound form) to analyze; to differentiate; to explain the meaning of something, as in 解析 jiěxī or 辨析 biànxī