19.In general,the cylindrical roller bearings, belonging to axial discerptible bearing,are suitable only for sustaining radial loads.The contact of roller with race is linear.
圆柱滚子轴一般只用于径向负荷,滚子与套圈滚道为线性接触,属轴向可分离型轴。
20.If the price efficiency underlying index after the listing of 50ETF isn’t improved, liquidity traders will sustain losses with information traders, speculator and arbitrager can’t profit.