相关实验视频

Updated: Jul 7, 2025

Investigating Long-Distance Transport of Perfluoroalkyl Acids in Wheat via a Split-Root Exposure Technique

Investigating Long-Distance Transport of Perfluoroalkyl Acids in Wheat via a Split-Root Exposure Technique

Published on: September 28, 2022

通过拉曼光谱解码PFAS污染:一个联合的DFT和机器学习调查

Yangxiu Chen¹, Yanjun Yang², Jiaheng Cui²

¹College of Physics, Sichuan University, Chengdu, China.

Journal of hazardous materials

|December 21, 2023

概括

密度函数理论 (DFT) 对40种 perfluoroalkyl物质 (PFAS) 的计算拉曼光谱揭示了不同的光谱指纹. 使用PCA和t-SNE进行高级分析,可以有效地区分这些PFAS化合物和异构体,以改善检测.

科学领域:

环境化学环境化学
分析化学分析化学
计算化学计算化学

背景情况:

perfluoroalkyl物质 (PFAS) 是普遍存在的环境污染物,需要强大的检测方法.
现有的PFAS识别分析技术可能是复杂和耗时的.
了解不同PFAS的独特光谱特性对于准确的环境监测至关重要.

研究的目的:

使用密度函数理论 (DFT) 计算和分析40种关键的 perfluoroalkyl 物质 (PFAS) 的拉曼光谱.
识别与特定的PFAS化学键和功能组相关的特征拉曼峰,振动模式和光谱区域.
研究分子结构 (异构体分支,链长,功能组) 对PFAS拉曼光谱的影响.

主要方法:

进行密度函数理论 (DFT) 计算以模拟拉曼光谱.
进行了光谱特征的系统比较,包括峰值位置和振动模式.
化学测量技术,主要成分分析 (PCA) 和t分布式静态邻居嵌入 (t-SNE) 被应用到光谱数据上.
创建了一个光谱数据库,使用受控噪声来增强差异化.

主要成果:

针对关键化学键 (C-C,CF2,CF3) 和功能组 (-COOH, -SO3H等) 确定了特定的拉曼光谱区域. ) 的情况.
分子结构变化 (同位素分支,链长,功能组) 已被证明显著影响光谱特征和峰值位置.
PCA和t-SNE有效地区分了40种PFAS化合物及其异构体,基于它们计算的拉曼光谱.

结论:

拉曼光谱学,结合DFT计算和化学分析,提供了一种强大的方法来区分各种PFAS化合物.
该研究为开发先进,快速和准确的PFAS检测和环境样本特征表征方法提供了基础.
产生的光谱数据库和分析方法对改善环境监测和监管合规性有很大的前景.

关键词:

密度函数理论计算计算密度函数理论计算机器学习机器学习 perfluoroalkyl 物质是一种高醇基物质.拉曼光谱法拉曼光谱法拉曼光谱法

更多相关视频

Identifying Per- and Polyfluorinated Chemical Species with a Combined Targeted and Non-Targeted-Screening High-Resolution Mass Spectrometry Workflow

Identifying Per- and Polyfluorinated Chemical Species with a Combined Targeted and Non-Targeted-Screening High-Resolution Mass Spectrometry Workflow

Published on: April 18, 2019

Detection and Quantification of Plasmodium falciparum in Aqueous Red Blood Cells by Attenuated Total Reflection Infrared Spectroscopy and Multivariate Data Analysis

Detection and Quantification of Plasmodium falciparum in Aqueous Red Blood Cells by Attenuated Total Reflection Infrared Spectroscopy and Multivariate Data Analysis

Published on: November 2, 2018

相关概念视频

Raman Spectroscopy: Overview

Raman Spectroscopy: Overview

The underlying principle of Raman spectroscopy is based on the interaction between light and matter, specifically molecules' inelastic scattering of photons. When a monochromatic beam of light, typically from a laser source, interacts with a sample, most scattered light has the same frequency as the incident light. This is known as Rayleigh scattering.
However, a small fraction of the scattered light exhibits a frequency shift due to the exchange of energy between the incident photons and...

Raman Spectroscopy Instrumentation: Overview

Raman Spectroscopy Instrumentation: Overview

A conventional Raman spectrophotometer includes a laser source, a sample holding system, a wavelength selector, and a detector.
The monochromatic laser source, typically using visible or near-infrared radiation, generates a highly focused beam of light. This light interacts with the molecules of the sample, scattering some of the light. Liquid and gaseous samples are usually tested in ordinary glass capillaries, while solids can be analyzed as powders packed in capillaries or as potassium...

¹³C NMR: Distortionless Enhancement by Polarization Transfer (DEPT)

¹³C NMR: Distortionless Enhancement by Polarization Transfer (DEPT)

When proton-coupled carbon-13 spectra are simplified by a broadband proton decoupling technique, structural information about the coupled protons is lost. Distortionless enhancement by polarization transfer (DEPT) is a technique that provides information on the number of hydrogens attached to each carbon in a molecule. While the DEPT experiment utilizes complex pulse sequences, the pulse delay and flip angle are specifically manipulated. The resulting signals have different phases depending on...