CX、CX^-和CX^+(X=F,Cl)解离的量子化学计算

用ａｂ ｉｎｉｔｉｏ 方法对ＣＸ、ＣＸ－和ＣＸ＋（Ｘ＝Ｆ，Ｃｌ）的解离及相应的原子或离子结构进行了量子化学计算。结果表明，对于Ｆ、Ｃｌ和Ｃ，第一电离势的顺序是Ｆ＞Ｃｌ＞Ｃ，第一电子亲和势的顺序是Ｃｌ＞Ｆ＞Ｃ，与文献报道相一致，绝热电子亲合势的计算表明，无论使用ａｂ ｉｎｉｔｉｏ 方法、ＬＤＡ方法还是ＬＤＡ／ＮＬ方法，结果证实阴离子要比其相应的中性分子稳定。ａｈ ｉｎｉｔｉｏ方法计算得到的各解离通道的解离能比文献值高大约 １．０～１．５ｅＶ。 ＣＸ、ＣＸ－和 ＣＸ＋解离的难易程度可以用 Ｆ、 Ｃｌ和 Ｃ的第一电离势和第一电子亲和势来说明。

Effects of water mist addition on kerosene pool fire

The use of water mist to extinguish fire is a problem of particular interest since the banning of halogen-based agents for environmental reasons. This interest is reflected in the large number of researches performed on the main fire-extinguishing mechanisms of water mist: heat extraction, oxygen displacement and attenuation of heat fluxes. In contrast, there are still little known about the chemical and some other aspects of water mist addition on the pool fire. In this paper, a phenomenological study was conducted of the effect of water mist addition on the kerosene pool fire through the measurement of the heat release rate, CO, CO2 and O2 species concentration in combustion. The experimental results show that there is a significant enhancement effect at the beginning stage of water mist addition. Then, the flame size was decreased abruptly. By physical suppression effect combined with chemical effect, the experiments' results are explained especially. The study of effects of water mist on pool fire will be useful for optimizing designation of water mist fire-suppression system, improving the fire suppression efficiency and extending their application field.