positive arc正弧positiveadj.积极的；肯定的；明确的；正面的；正数的；阳性的n.正面；正数；正片；[语]原级positive-ion current阳离子电流positive stereotropism[医] 阳性向实体性, 亲实体性positive whole numbers正整数positively normal cone正法锥positive bending model正弯模型positive orbit closure正轨道闭包positive random series正项随机级数positive friction role积极摩擦作用positively charged ion阳离子,正离子positive feature words正特征词