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介绍了枪钻的结构特点以及加工时数控机床所需具备的硬件要求,通过对不同材料或直径枪钻切削参数的合理选择及计算,能有效地解决在数控机床上完成深孔加工时的排屑、冷却和钻孔轴线歪斜等问题。 相似文献
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La0.75NbO4:Eu3+0.25 and La0.65NbO4:Eu3+0.25,Bi3+0.10 phosphors were synthesized by solid-state reaction method,and their photoluminescence properties were discussed in detail.With the increased incorporation of the co-activator Bi3+,the charge transfer(CT) bands of Nb5+→O2-and Eu3+→O2-(-280 nm) weakened and a new and significant broad band Bi3+-O2-(-330 nm) appeared,while the peaks at 395 and 466 nm assigned to f-f transitions of Eu3+ was slightly changed.Compared with the commercial phosphor Y2O2S:0.05Eu3+... 相似文献