发烟硫酸含三氧化硫酸的一种腐蚀性溶液。

A corrosive solution of sulfur trioxide in sulfuric acid.

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以废聚苯乙烯（WPS）泡沫为原料，采用浓硫酸和发烟硫酸两种磺化方法制备性能良好的砼减水剂。

The PS water reducing agent, which is very effective for concrete, has been made from waste poly styrene(WPS) by sulfuric acid of fuming sulfuric acid sulfonation process.

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经过多次试用，其操作时间和得到的结果，与以前使用的硫酸、硝酸加发烟硫酸的方法基本相同。

This method has been used for many times and similar operation time and product are obtained as that using the treatment with a mixture of sulfuric acid, nitric acid and fuming sulfuric acid.

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