使用机器学习模型预测素物种和微量有机污染物的反应动态
Jingyi Zhu1, Yuanxi Huang1, Qihang Yi2
1Hunan Engineering Research Center of Water Security Technology and Application, College of Civil Engineering, Hunan University, Changsha, 410082, PR China.
Chemosphere
|November 10, 2023
概括
机器学习模型预测素物种和微量有机污染物的反应速率 (k) 值. 这些模型使用分子描述符和指纹准确估计未知的k值,帮助机械学理解.
科学领域:
- 环境化学环境化学
- 计算化学计算化学
- 化学动力学 化学动力学
背景情况:
- 活性基物种 (基,基,二基离子) 和微量有机污染物 (TrOCs) 之间的反应对环境过程至关重要.
- 速率常数 (k 值) 对于理解这些反应机制至关重要,但对于许多TROC来说通常是不可用的.
- 需要预测模型来估计这些基本的动力参数.
研究的目的:
- 开发基于机器学习 (ML) 的定量结构-活性关系 (QSAR) 模型,用于预测具有TROC的活性素物种的反应速率常数 (k).
- 确定最佳的ML算法和分子表示 (分子描述符和指纹) 以准确预测k值.
- 为了获得对影响不同素物种反应性的因素的机械洞察力.
主要方法:
- 评估了五种ML算法:随机森林,神经网络,XGBoost,支持矢量机 (SVM) 和多线性回归.
- 分子描述符 (MDs) 和分子指纹 (MFs) 被用作QSAR模型的输入特征.
- 用SHAP分析来解释模型,以了解预测驱动因素和机制关系.
主要成果:
- 最佳模型实现了高预测精度:MD-XGBoost用于Cl• (R2test=0.876) 和Br• (R2test=0.743),以及MF-SVM用于Cl2•− (R2test=0.853).
- 与Cl•和Br•相比,取电子/捐电子组显著影响了Cl2•−的反应性.
- 输入特征的选择 (MDs与MFs) 是至关重要的,MDs更适合Cl•/Br•,MFs更适合Cl2•−.
结论:
- 开发的ML-QSAR模型提供了可靠的工具,用于预测素物种和TROC的未知反应速率常数 (k值).
- 这些模型提供了统计学上合理的预测和对影响反应性的因素的机制性见解.
- 这些预测工具可以加速环境化学和污染物降解途径的研究.
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