differential arc差动电弧differentialadj.差别的；特定的；微分的n.差别；工资差额；差动齿轮；[数]微分differential electrometer差动静电计,差动电位计differential demodulation差分解调differential premium rate差别保险费率differential box counting差分盒子法differential distillation微分蒸馏differential spectroscopy差示光谱法differential of reactance电抗微分(符号)differential selsyn motor差动自动同步机differential relief valve差压溢流阀differential refleetivity差分反射率因子