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This paper makes an introduction of a new type equipment of mineralprocessing——the whirl panning machine.

本文简要介绍了一种新型的选矿设备——涡流淘金机的构造和分选过程以及它应用在采金船尾矿中回收黄金的效果,最后,讨论了几个影响因素,并指出了这种设备的应用前景。

Cities Founded on Gold-mines——The Gold Rush and the Emergence of Cities in Alaska;

奠基在金矿上的城市——淘金热与阿拉斯加城市的兴起

Based on this topic, the paper will focus on three large-scale gold rushes and the gold miners living.

淘金热是采矿业初始阶段即浅层矿开采的主要形式，它在美国历史上占有重要的地位。