一种用于测量海水中氨的便携式分析仪。

A portable analyser for the measurement of ammonium in marine waters.

机构信息

Cooperative Institute for Marine and Atmospheric Studies (CIMAS), Rosenstiel School of Marine and Atmospheric Science, University of Miami, 4600 Rickenbacker Causeway, Miami, FL 33149, USA.

出版信息

Environ Sci Process Impacts. 2013 Mar;15(3):579-84. doi: 10.1039/c2em30793f.

DOI:10.1039/c2em30793f

PMID:23738356

Abstract

A portable ammonium analyser was developed and used to measure in situ ammonium in the marine environment. The analyser incorporates an improved LED photodiode-based fluorescence detector (LPFD). This system is more sensitive and considerably smaller than previous systems and incorporates a pre-filtering subsystem enabling measurements in turbid, sediment-laden waters. Over the typical range for ammonium in marine waters (0–10 mM), the response is linear (r(2) = 0.9930) with a limit of detection (S/N ratio > 3) of 10 nM. The working range for marine waters is 0.05–10 mM. Repeatability is 0.3% (n =10) at an ammonium level of 2 mM. Results from automated operation in 15 min cycles over 16 days had good overall precision (RSD = 3%, n = 660). The system was field tested at three shallow South Florida sites. Diurnal cycles and possibly a tidal influence were expressed in the concentration variability observed.

摘要

一种便携式氨分析器已经被开发出来，并用于测量海洋环境中的原位氨。该分析器采用了改进的基于 LED 光电二极管的荧光检测器（LPFD）。与以前的系统相比，该系统的灵敏度更高，体积也小了很多，并且还集成了一个预过滤子系统，使其能够在浑浊、含沉积物的水域中进行测量。在海洋水中氨的典型范围内（0-10 mM），响应是线性的（r(2) = 0.9930），检测限（S/N 比>3）为 10 nM。海洋水的工作范围为 0.05-10 mM。在 2 mM 氨水平下，重复性为 0.3%（n = 10）。在 16 天内 15 分钟自动运行的结果具有良好的整体精密度（RSD = 3%，n = 660）。该系统在佛罗里达州南部的三个浅滩进行了现场测试。在观测到的浓度变化中，表现出昼夜循环，可能还有潮汐的影响。