After modified design, the M-827 measuring rule used to measure step diameter can measure the actual dimension deviation of machined parts directly and quality of the parts is improved too.
改进设计的M—827止口直径测量尺能够直接测量出被加工零件的实际加工尺寸偏差，提高零件加工质量。
In general can be twist drill hole, but you should drill holes, step and then expanded to the required diameter.
用一般的麻花钻即可开孔，但应先钻小孔，然后步扩大到所需直径。
Methods: Prepared the monodisperse and big diameter crosslinked polystyrene microspheres with Two Step Swelling Method, Using diVinylbenzene as the crosslink agent.
方法：以苯乙烯为单体，二乙烯苯为交联剂，采用二步溶胀法合成单分散、大粒径的聚苯乙烯高分子微球。
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