Application of New Mass Caving Technology of Bunch-Hole Equivalent Spherical Charge;
束状孔当量球形药包大量落矿采矿新技术研究
A new method for rapid separation and determination of trace tantalum in copper mass is presented.
提出了一个快速分离与测定大量铜中微量钽的新方法。
Using equal diameter steel wires to strand,ensuring not to skip steel wire during stranding,thickened value of core steel wire is different with different structure of strands.
用等直径钢丝组股时,为保证在捻股时不出现跳丝,中心钢丝的加大量应根据所捻制股结构的不同而不同;组股钢丝层数越多,中心钢丝加大量应再适当增加;仅根据外层钢丝大小对中心钢丝进行加大是不合适的。