a weak poisonous liquid acid; formed by solution of hydrogen fluoride in water

the reversed mud acid is the mud acid whose concentration and volume of hydrofluoric acid is higher than that of hydrochloric acid, its treatment mechanism is identical to the mud acid.

逆土酸系指氢氟酸浓度和用量高于盐酸浓度和用量的土酸，它处理地层的机理与土酸相同。

the hitch of the canned-motor pump for delivering hydrofluoric acid was analyzed. the corresponding transformation was conducted in order to guarantee the pump running long period.

分析了输送氢氟酸的液下屏蔽泵产生故障的原因，进行了相应的改造，保证了屏蔽泵的长周期稳定运行。

hydrofluoric acid (hf), a colorless inorganic acid with mild irritating odor, is used extensively in various industries, such as the semiconductor industry and the electropolishing of metal.

氢氟酸（hf）为一无色略带刺激味的无机酸，普遍地被使用于各种工业，如半导体工业及金属除锈等。

the fluorspar is mainly used in chemical industry, as main raw material to produce anhydrous hydrofluoric acid and as the basic raw material of fluoration chemistry.

氟石在化工行业，主要用作生产无水氢氟酸的主要原材料和进行氟化处理的基本原料；

the comparative tests show that the content of silicon dioxide in carbon materials determined by the melting method (mm) is more stable and accurate than the hydrofluoric acid method (mha);

通过对比试验发现：测定炭素材料中二氧化硅的含量，熔融法的分析结果比氢氟酸法更稳定、準确；

the converting film obtained by hydrofluoric acid treatment has better protection for the body of magnesium alloy. it's feasible to electroplate al on mgf2 passivation film.

结果表明，氢氟酸处理得到的氟化镁转化膜对镁合金基体有较好的保护作用，在氟化镁钝化膜上电镀铝是可行的。

the re fluoride can be prepared directly from oxalate by adding hydrofluoric acid . the ratio of transformation and recovery is high if the hydrofluoric acid is added by 120% theoretical amounts.

稀土草酸盐中直接加氢氟酸置换生成氟化稀土，选择加入120%理论量的氢氟酸有较高的转化率和回收率。

a new type filler, ptfe ladder rasching ring is designed and used in the washing tower of anhydrous hydrofluoric acid equipment, properties of this filler is also analyzed.

设计了1种新型填料―ptfe阶梯拉西环并应用在无水氢氟酸装置的洗涤塔中，分析了该填料的特性。

if oxygen content existing in hydrofluoric acid is much higher, its corrosion-resistant performance will weaken. in sodium hydroxide with high thickness, its corrosion-resistant performance is worse.

在测量介质氢氟酸中进入的氧量多时，耐蚀性会下降，在高浓度的氢氧化钠中，耐蚀性较差。