相关实验视频

Updated: Jan 8, 2026

Characterization, Quantification and Compound-specific Isotopic Analysis of Pyrogenic Carbon Using Benzene Polycarboxylic Acids BPCA

Characterization, Quantification and Compound-specific Isotopic Analysis of Pyrogenic Carbon Using Benzene Polycarboxylic Acids BPCA

Published on: May 16, 2016

二氧化碳合成方法与被动采样技术相结合,用于大气CO2中的14C测量

Bommadeni Arun¹, Neha Ashok Fulzele¹, Menaka M¹

¹Safety, Quality, and Resource Management Group, Indira Gandhi Centre for Atomic Research, Kalpakkam, Tamilnadu 603102, India.

Radiation protection dosimetry

|December 13, 2025

概括

这项研究使用被动采样和合成测量了大气中二氧化碳 (CO2) 中的碳-14 (14C) 活性. 在大气中的CO2中,14C的平均特异活性被确定为246.3±2.5 Bq/kg C.

科学领域:

环境科学环境科学
放射化学放射化学是指辐射化学.
大气化学大气化学

背景情况:

在大气中的二氧化碳 (CO2) 中精确测量碳-14 (14C) 对环境监测和气候研究至关重要.
被动采样为收集大气样本提供了一种具有成本效益和可访问性的方法.
合成是一种可靠的方法,用于制备液体闪计数样品.

研究的目的:

测量14C在大气CO2中的特异活性.
为了验证被动采样技术与合成相结合,用于大气二氧化碳分析.
为了确定大气中基线14C水平.

主要方法:

使用被动采样技术收集大气中的二氧化碳,将其吸收到2N氧化 (NaOH) 溶液中.
吸收的二氧化碳被合成成,使用气相色谱检验纯度为99%.
使用与NIST标准校准的液体闪计数器测量14C活动,系统效率为70.2%±0.8%.

主要成果:

在7天内2N NaOH溶液中吸收的平均碳量为5.27 ± 0.20 g.
在大气二氧化碳中测量的14C的特定活性水平在240.9至250.0 Bq/kg C.之间.
在大气中的CO2中,14C的平均特异活性被确定为246.3±2.5 Bq/kg C.

结论:

与合成相结合的被动采样技术是确定大气CO2中的14C特异活性的一种可行的方法.
该研究提供了有关大气当前14C水平的重要数据.
这种方法可用于长期大气监测和研究.

更多相关视频

Measuring Carbon-based Contaminant Mineralization Using Combined CO2 Flux and Radiocarbon Analyses

Measuring Carbon-based Contaminant Mineralization Using Combined CO2 Flux and Radiocarbon Analyses

Published on: October 21, 2016

Calibrated Passive Sampling - Multi-plot Field Measurements of NH3 Emissions with a Combination of Dynamic Tube Method and Passive Samplers

Calibrated Passive Sampling - Multi-plot Field Measurements of NH3 Emissions with a Combination of Dynamic Tube Method and Passive Samplers

Published on: March 21, 2016

相关概念视频

¹³C NMR: ¹H–¹³C Decoupling

¹³C NMR: ¹H–¹³C Decoupling

The probability of having two carbon-13 atoms next to each other is negligible because of the low natural abundance of carbon-13. Consequently, peak splitting due to carbon-carbon spin-spin coupling is not observed in spectra. However, protons up to three sigma bonds away split the carbon signal according to the n+1 rule, resulting in complicated spectra.
A broadband decoupling technique is used to simplify these complex, sometimes overlapping, signals. Broadband decoupling relies on a...

NMR Spectroscopy of Benzene Derivatives

NMR Spectroscopy of Benzene Derivatives

Simple unsubstituted benzene has six aromatic protons, all chemically equivalent. Therefore, benzene exhibits only a singlet peak at δ 7.3 ppm in the 1H NMR spectrum. The observed shift is far downfield because the aromatic ring current strongly deshields the protons. Any substitution on the benzene ring makes the aromatic protons nonequivalent, and the protons split each other. The peak is, therefore, no longer a singlet and the splitting pattern and their associated coupling...