Experiment was discovered: the impurity of the alloy billet produced by direct resistance sintering was lower, than by activated sintering and medium-frequency induction sintering.

试验发现：垂熔烧结可获得较低杂质含量的合金坯料，活化烧结和中频感应烧结获得的坯料杂质含量较高。

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Using zinc oxide mine as a raw material, activated zinc oxide can be produced by ammonia leaching, getting rid of impurity, depositing zinc, drying and calcining.

以锌焙砂为原料，经氨浸，除杂，沉锌，干燥，煅烧等工序制取了活性氧化锌。

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