相关实验视频

Updated: Jul 18, 2025

Clean Sampling and Analysis of River and Estuarine Waters for Trace Metal Studies

Clean Sampling and Analysis of River and Estuarine Waters for Trace Metal Studies

Published on: July 1, 2016

确定水性在生态系统中的同位素组成,使用薄膜中的扩散梯度

Hongqian Yin^1,2, Heng Yao¹, Wei Yuan¹

¹State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550081, China.

Analytical chemistry

|August 22, 2023

概括

使用功能化纳米颗粒的新DGT (薄膜扩散梯度) 方法有效测量水中的同位素. 这种被动采样技术有助于了解.

科学领域:

环境化学环境化学
分析化学分析化学
地质化学地质化学

背景情况:

测量超微量水性 (Hg) 同位素是困难的,因为度低 (ng L-1),需要大量的水量 (>10 L),并带来污染的风险与传统的采集采样.
精确的Hg同位素分析需要至少5 ng的Hg质量,这对于自然水样来说是一个重大挑战.
传统方法是劳动密集型,耗时,在样品处理和预缩过程中容易受到污染.

研究的目的:

开发和验证一种新的薄膜扩散梯度 (DGT) 方法,用于确定水性的度和同位素组成.
评估DGT方法在Hg吸附过程中诱导的质量依赖分化 (MDF) 和质量独立分化 (MIF).
评估DGT方法在污染水环境中的Hg生物地球化学循环的表征方面的有效性.

主要方法:

使用aminopropyl和mercaptopropyl双功能SBA-15纳米颗粒用于Hg吸附的DGT设备的开发.
通过DGT对Hg吸附的实验室分析,量化诱导的MDF和MIF.
现场部署DGT方法与传统的采集采样一起用于对Hg同位素特征进行比较分析.

主要成果:

实验室测试表明,Hg的DGT吸附会诱导大约-0.2‰的MDF和最小的MIF,MDF受扩散层厚度的影响.
现场结果表明,DGT方法和采样采样之间的一致的MIF签名 (Δ199Hg).
DGT方法在描述水性Hg MIF方面被证明是有效的,这对于理解Hg生物地球化学循环至关重要.

结论:

开发的DGT方法提供了一种被动且有效的方法来分析水中的度和同位素组成.
由于潜在的环境过程影响,建议在解释DGT的Hg-MDF数据时谨慎使用.
DGT方法成功地描述了Hg MIF,提供了有关Hg在受污染地点的生态化学循环的宝贵见解.

更多相关视频

Speciation and Bioavailability Measurements of Environmental Plutonium Using Diffusion in Thin Films

Speciation and Bioavailability Measurements of Environmental Plutonium Using Diffusion in Thin Films

Published on: November 9, 2015

Two-Dimensional Visualization and Quantification of Labile, Inorganic Plant Nutrients and Contaminants in Soil

Two-Dimensional Visualization and Quantification of Labile, Inorganic Plant Nutrients and Contaminants in Soil

Published on: September 1, 2020

相关概念视频

Voltammetric Techniques: Linear-Scan (E vs Time)

Voltammetric Techniques: Linear-Scan (E vs Time)

Polarography is a classical voltammetric technique used to analyze electrochemical reactions. This method applies a linear potential sweep to a dropping mercury electrode (DME), and the resulting current is measured. A dropping mercury electrode is commonly used as the working electrode in polarography. It consists of a capillary tube filled with mercury, where the tiny droplet forms at the tip. This droplet continuously drops from the capillary, creating a new electrode surface for each...

Precipitation Gravimetry

Precipitation Gravimetry

Precipitation gravimetry is based on converting an analyte into a sparingly soluble precipitate, which is separated by filtration and weighed. An ideal precipitate should be pure, insoluble, of known composition, and easily filtered from the reaction mixture.
In determining nickel by gravimetric analysis, a precipitant of ethanolic dimethylglyoxime is added to a hot nickel salt solution. This is quickly followed by the dropwise addition of dilute ammonia solution until precipitation occurs. A...

Gravimetry: Overview

Gravimetry: Overview

Gravimetric analysis is a quantitative method where the analyte is isolated and weighed directly or after conversion into a substance of known composition. Gravimetric analysis can be classified as precipitation, electrogravimetry, volatilization, and particulate gravimetry, based on the method used to isolate the analyte.
In precipitation gravimetry, the analyte is converted into a precipitate and weighed. For example, the silver content in a sample can be estimated by precipitating and...