A new DGT technique comprised in a hybrid sensor for the simultaneous measurement of ammonium, nitrate, phosphorus and dissolved oxygen
A new DGT technique comprised in a hybrid sensor for the simultaneous measurement of ammonium, nitrate, phosphorus and dissolved oxygen
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混合传感器中包含的新型 DGT 技术可同时测量铵、硝酸盐、磷和溶解氧
DOI：
10.1016/j.scitotenv.2020.138447
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发表时间：
2020
影响因子：
9.8
通讯作者：
Yan Wang
中科院分区：
文献类型：
--
作者：
Mingyi Ren;Shiming Ding;Dan Shi;Zhilin Zhong;Jingxin Cao;Liyuan Yang;Daniel C.W.Tsang;Dan Wang;Donghua Zhao;Yan Wang
本文提出了一种新的薄膜扩散梯度技术（ZrO-AT DGT），将氧化锆、A-62 MP和T-42 H树脂包埋在同一凝胶中，同时测定硝酸盐（NO_3-N）、铵（NH_4-N）和磷酸盐（PO_4-P）。发现DGT摄取与pH值从3.2-8.7的变化无关。低于5、10和750 mmol·L-1 NaCl的离子强度不影响DGT对NH 4-N、NO3-N和PO 4-P的吸收。这种新的DGT被部署在天然淡水环境中，对三种营养物质的原位测量被发现是准确的。它确保了每隔3天冲洗DGT装置的暴露表面可以防止生物污垢。此外，混合传感器包括新的DGT结合层覆盖O2平面光极进行了测试，在沉积物中，以评估O2和三种营养物质的动力学。结果表明，好氧条件下，PO 4-P和NO3-N通量降低，NH 4-N通量增加。O2和NO3-N在沉积物-水界面（SWI）上几乎同时发生变化，NO3-N和PO 4-P的转化受O2动态的敏感影响。
A new diffusive gradients in thin films technique (ZrO-AT DGT) with zirconium oxide, A-62 MP and T-42H resins containing in a single binding gel was developed for simultaneous measurement of nitrate (NO3-N), ammonium (NH4-N) and phosphate (PO4-P). The DGT uptake was found to be independent of pH variation from 3.2–8.7. Ionic strengths below 5, 10 and 750 mmol·L−1NaCl did not affect DGT uptake of NH4-N, NO3-N and PO4-P, respectively. This new DGT was deployed in natural freshwater environments, with in situ measurements of the three nutrients found to be accurate. It ensured that rinsing the exposed surface of the DGT device at 3-day intervals can prevent biofouling. Additionally, a hybrid sensor comprising the novel DGT binding layer overlying an O2planar optrode was tested in sediments to evaluate the dynamics of O2and the three nutrients. Results showed that PO4-P and NO3-N fluxes decreased while fluxes of NH4-N increased under aerobic conditions. Nearly simultaneous variation in O2and NO3-N was observed at the sediment-water interface (SWI) and transformation of NO3-N and PO4-P was found to be sensitively influenced by O2dynamics.