fractional ppb分数ppbfractionaladj.微不足道的；断片的；分数的；小数的fractional horsepower induction motor分马力感应式电动机Fractional-Orbit Bombardment System部分轨道轰炸系统fractional horse power induction motor分马力感应电动机fractional differential cover operator掩模算子fractional efficiency by particle size分粒径计数效率fractional-order Wigner distribution分数阶Wigner分布fractional semi-infinite programming分式半无限规划fractional - N frequency synthesizer小数频率合成器fractional-order differential system分数阶微分系统fractional-order disturbance observer分数阶干扰观测器

1. Sharebuilder allows you to buy stocks in fractional amounts, making it much easier to invest.
   股票建设者可以让你零金额购买股票，这让投资更容易了。