Determination of Boron Trifluoride in Boron Trifluoride Complex by Fluoride Ion Selective Electrode

A method was proposed to determine boron trifluoride in boron trifluoride complex using fluoride ion selective electrode(ISE). Hydroxide was chosen to mask aluminum for the determination of 0.01—0.1 mol/L of fluoride. The simulation indicated that the permissible aluminum masked at a certain p H value was limited and hardly related to F-concentration and boric acid. It is better to control p H value below 11.5 and the aluminum concentration within 0.025 mol/L to minimize the interference of hydroxide to the fluoride ISE. The decomposition conditions of boron trifluoride by aluminum chloride were investigated. It is found that the F-detection ratio will approach 1.0 if the Al/F molar ratio is 0.3—0.7 and aluminum concentration is no more than 0.02 mol/L when heated at 80 ℃ for 10 min. In one word, hydroxide is quite fit to mask aluminum for samples which contain high content of fluoride and aluminum and the BF3 content can be successfully determined by this method.

氢氧化铝表面硼吸附络合物结构状况的解析

对Ａｌ（ＯＨ）３＋Ｈ３ＢＯ３，Ａｌ（ＯＨ）３，Ｈ３ＢＯ３等样品进行了红外光谱、红外差分谱以及Ａｌ（ＯＨ）３＋Ｈ３ＢＯ３的二次离子质谱（ＳＩＭＳ）分析。结果表明，Ａｌ（ＯＨ）３＋Ｈ３ＢＯ３样品在１４２３和１２７９ｃｍ－１处有２个特征吸收峰，这些峰与Ｈ３ＢＯ３表现出的吸收峰相比，峰带更宽，说明在Ａｌ（ＯＨ）３＋Ｈ３ＢＯ３处理中，Ａｌ（ＯＨ）３表面形成了一种新物质，即硼的吸附络合物。氢氧化铝表面硼吸附络合物的ＳＩＭＳ图谱表明，硼在Ａｌ（ＯＨ）３表面高度密集，反映了这一表面结构状况中铝硼原子比例不同于简单的硼铝混合物。

Q235钢热浸渗铝复合渗硼层耐磨性的研究

用MM2型磨损试验机,在实验室条件下,对热浸渗铝和热渗铝复合渗硼试样进行了耐磨性的对比试验,并采用扫描电镜对磨损后的形貌进行观察分析。结果表明,在干摩擦条件下,热浸渗铝复合渗硼较单独热浸渗铝具有更好的耐磨性能。热浸渗铝的磨损机制以粘着磨损为主;而热浸渗铝复合渗硼以磨粒磨损为主要机制,同时伴有粘着磨损。