一种机器学习方法,用于预测大气相关有机化合物的纯成分表面张力
Ryan Schmedding1, Mees Franssen1, Andreas Zuend1
1Department of Atmospheric and Oceanic Sciences, McGill University, Montreal, Quebec H3A 0B9, Canada.
概括
预测大气气溶中有机化合物的表面张力对于了解它们对气候的影响至关重要. 机器学习模型准确地估计了这些属性,改进了气溶激活模拟.
科学领域:
- 大气化学和物理大气化学和物理
- 环境科学环境科学
- 计算化学是一种计算化学.
背景情况:
- 大气中的气溶是复杂的混合物,通过云相互作用和化学反应影响气候.
- 由有机化合物影响的粒子表面特性是气溶行为的关键.
- 对于许多有机化合物在热层温度下的实验表面张力数据很少.
研究的目的:
- 开发和验证机器学习模型,用于预测有机化合物与大气气溶相关的温度依赖的纯成分表面张力.
- 为了解决对大气相关有机化合物缺乏实验数据的问题.
- 评估预测的表面张力对气溶激活过程的影响.
主要方法:
- 编制了各种有机化合物和温度的实验纯成分表面张力数据的数据库.
- 训练了四个机器学习模型,使用分子结构 (SMILES) 和温度作为输入.
- 利用极端梯度增强下降与MACCS关键描述符,以实现最佳模型性能.
- 为不完整的结构数据开发了一个使用摩尔质量,元素比率和温度的简化模型.
主要成果:
- 使用MACCS描述符的极端梯度增强模型实现了~1mJ m-2的根平均平方误差 (RMSE) 进行表面张力预测.
- 一个简化的模型在分子结构信息不完整的情况下,实现了~2mJ m-2的RMSE.
- 预测的表面张力值显著改变了热力学模型中气溶激活的临界超和值.
结论:
- 机器学习有效地预测了大气相关有机化合物的表面张力,填补了关键数据缺口.
- 开发的模型提供了准确的估计,即使有不完整的分子信息.
- 准确的表面张力预测对于完善气候模型和了解气溶与云的相互作用至关重要.
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