No abstract

Mercury (Hg) is one of the heavy metal pollutants in the environment. Even a very small amount of mercury can cause serious harm to human beings. Herein, we reported a new carbonothioate-based fluorescent probe for the detection of Hg without interference from other metal ions. This probe possessed a very large Stokes shift (192 nm), which could improve the detection sensitivity by minimizing the interferences resulted from self-absorption or auto-fluorescence. With the addition of Hg to the probe solution, considerable fluorescence enhancement was observed. Additionally, the Hg concentration of 0-16 μM and fluorescence intensity showed a good linear relationship (y = 22106× + 53108, R = 0.9955). Finally, the proposed probe was used to detect Hg in real water samples, and its result was satisfactory. Therefore, our proposed probe would provide a promising method for the determination of Hg in the environment.

No abstract

The Interconnected River System Network (IRSN) has become a popular and useful measure to realize the long-term health and stability of water bodies. However, there are lots of uncertain consequences derived from natural and anthropogenic pressures on the IRSN, especially the water pollution risk. In our study, a Vine Copula-based model was developed to assess the water pollution risk in the IRSN. Taking the ponds around Nanyang station as research objects, we selected five proxy indicators from water quality indexes and eutrophication indexes, which included dissolved oxygen (DO), total nitrogen (TN), total phosphorus (TP), chlorophyll-a (Chla), and ammonia nitrogen (NH3-N). Models based on three classes of vine copulas (C-, D-, and R-vine) were utilized respectively to identify the water quality indicators before and after the operation of the connection project. Our results showed that TN, Chla, and NH3-N should be considered as key risk factors. Moreover, we compared the advantages and prediction accuracy of C-, D-, and R-vine to discuss their applications. The results reveal that the Vine Copula-based modeling could provide eutrophication management reference and technical assistance in IRSN projects.