CHF2Brの大気中の寿命は,ハロンの代替品として提案されている
まとめ
CHF(2) Brとヒドロキシルラジカル (OH) の反応速度を測定し,CHF(2) Brの大気中の寿命が類似化合物と比較して約7年短かったことを明らかにしました.
科学分野:
- 大気化学 大気化学
- 化学動力学 化学動力学
背景:
- 大気中のハロ炭素の運命を理解することは,その環境への影響を評価するために極めて重要です.
- CHF ((2) Brはオゾン層の破壊に潜在的関連性を持つハロカーボンである.
研究 の 目的:
- OHとCHFの反応の速度係数を決定する.
- CHFの紫外線吸収の断面を測定するために,Br.
- CHF (((2) Br.Br.の大気中の寿命とオゾン層の破壊の可能性を計算する.
主な方法:
- パルス光解と放電フローのテクニックを使用して,233Kから432Kまでの温度で反応速度係数を測定しました.
- 紫外線吸収の断面は296Kで測定されました.
- 一次元の大気モデルが利用されました.
主要な成果:
- OH + CHF ((2) Br反応の速度係数 k ((1) は (7.4 +/- 1.6) x 10 ((-13) exp[- ((1300 +/- 100) /T]cm ((3) /分子/s.と決定されました.
- CHF ((2) Brの大気中の寿命は,およそ7年であると計算されました.
- この寿命は,CF(3) BrとCF(2) Cl.Brの寿命よりも大幅に短くなります.
結論:
- CHF ((2) Brは,CF ((3) BrとCF ((2) ClBrと比較して,大気中の寿命が短い.
- 決定された運動パラメータと寿命は,これらの化合物と比較してCHF ((2) Brのオゾン破壊の可能性が低いことを示唆しています.
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