dubious是什么意思啊 degradation是什么意思 degradation的中文意思

degradation是什么意思 degradation的中文意思  

英音 [degrə'deiʃən] ;,美音 [degrə'deiʃən] ;,名词
降格，堕落，退化,形容词 degradative,changing to a lower state (a less respected state),a low or downcast state,biological degradation 生物体退化,alkaline degradation 碱降解,energy degradation 能量损失,degradation product 降解产物,degradation reaction 降解反应,thermal degradation 热降解，热降解作用,color degradation 【建】 变色,colour degradation 【化】 变色(汽油、灯油等油品),photooxidative degradation 光氧化降解,picture degradation 图像变劣,degradation n. 降格，堕落，退化,self degradation n. 自暴自弃,heat degradation 热降解