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以红土镍矿硫酸焙烧-浸出所得浸出液为原料,利用氨水调节溶液的pH值,进行铁、镍的分离与回收研究。通过探索温度、pH值对浸出液中铁、镍、镁离子沉淀的影响,得出沉淀铁离子的适宜条件为:温度30℃,pH=4.0,铁的沉淀率可达到99%以上,镍、镁沉淀率小于4%;沉淀镍离子的适宜条件为:温度60℃,pH=7.0,镍的沉淀率可达到95.5%以上,镁沉淀率低于10%。本研究所提出的分步水解法分离、回收有价金属的工艺将为红土镍矿硫酸法浸出液的综合利用提供技术指导。 相似文献
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龚嘴水电站4 号溢洪门钢丝绳运行多年,出现了断丝现象,严重威胁溢洪门的安全,必须对钢丝绳进行更换。 在分析不同钢丝绳更换方法优缺点的基础上,选择了用旧钢丝绳带动新钢丝绳上卷筒的最优更换方法,顺利完成了溢洪门钢丝绳的更换。 溢洪门有水启闭试验显示钢丝绳更换后各机构运行状态良好,表明此种钢丝绳更换方法具有风险小、效率高、花费时间少、成本低等优点。 相似文献
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Density functional theory (DFT) was applied at the B3LYP/6-31G^* level to investigate the relative stability of the five fullerene isomers as well as the anions of C78. Full geometry optimization was carried out and distributions of electrostatic potential were calculated. The results showed that the C78(D3h′) cage was the most stable for C78^q-( q = 2, 4, 6), and the potential minimum Vmin(r) inside the sphere of C78(Dzh′) was the biggest one among the five isomers of C78. So C78(Dzh′) were electrons from the scandium atoms that were easier to accept than the other four isomers. On the other hand, MEP maps inside the sphere of C78(Dzh′) had three minima near the three vertexes. Each vertex was formed by the intersection of the three hexagons. Our results allowed a possible explanation for the bonding between the scandium atoms and the fullerene cage. 相似文献
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本文对燃油加油机新,旧检定规程中的计算公式进行了分析。阐述了新规程中计算公式的科学性。 相似文献