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A dual-function cellulose nanofiber (CNF)-based bionic biosensor with good biocompatibility was developed for detecting Ag+ and acetylcholinesterase (AChE) by grafting deoxyribonucleic acid (DNA) onto CNF. The Ag+ ions captured by the biosensor acted as recognition sites for the detection of AChE. The CNF-based bionic biosensor (CNF-DNA) could detect Ag+ concentrations as low as 10-6 nM in the presence of interference metal ions (Hg2+, Ba2+, Cd2+, Mg2+, Mn2+, Pb2+, and Zn2+). DNA-template silver nanoclusters (DNA-AgNCs) were formed on the surface of CNF-DNA during the detection of Ag+ (CNF-DNA-AgNCs). This new strategy yielded CNF-DNA-AgNCs through the adsorption of Ag+ ions onto the cytosine base of the single-stranded DNA in CNF-DNA without the use of any additional reducer. Meanwhile, the CNF-DNA-AgNCs exhibited excellent sensitivity and selectivity for trace levels (0.053 mU/mL) of AChE in the presence of interference reagents. The novel strategy proposed in this paper may establish a foundation for further research on DNA-template AgNCs for developing biosensors and biomarkers for in vivo and in vitro detection.In order to remove and stabilize As(III) simultaneously from wastewater, a novel and effective method based on the in-situ formation of As(III)-containing Zn-Fe layered double hydroxides (ZnFe-As-LDHs) was developed. The influence of pH, Zn/Fe, Fe/As and adding rate on the formation of ZnFe-As-LDHs were investigated. Under the optimal conditions, the concentration of As(III) decreased from 100 to 0.13 mg/L and As leaching concentration of the ultimate sludge was 1.87 mg/L, which could meet the arsenic leaching criteria (5 mg/L) regulated by US EPA. Compared with the "ex-situ" sludge obtained by As(III) adsorbed on the pre-formed ZnFe-LDHs, the As(III) removal efficiency increased by 21.6 % and the stability of the sludge increased by 94.2 % on the in-situ formation of LDHs, which mainly attributed to 55.06 % oxidation of As(III) and co-precipitation of As with Zn and Fe. Additionally, a possible in-situ formation pathway for ZnFe-As-LDHs was illustrated. At the beginning of the process, non-crystalline ferric arsenate formed and then transformed to amorphous ferrihydrite as precursors, followed by the formation of LDHs. This work demonstrated that co-precipitating As with Zn and Fe in the wastewater to in-situ form LDHs exhibited excellent potential for removal and direct stabilization of As(III).Estuarine systems are vulnerable to metals stress, such as copper (Cu). Thus, the development of applicable tools to improve routine monitoring programs is increasingly necessary. In the present work a comprehensive Ecological Risk Assessment (ERA) was implemented by coupling the Measured Environmental Concentration (MEC), based on labile Cu (DGT) and the total dissolved Cu concentration. Additionally, toxicity data related to site-specific Predicted No Effect Concentration (PNEC) were used. As case study, estuarine areas were selected on Brazilian coast, previously reported as Cu release in shipyard areas. The results indicated an increase in concentrations of dissolved and labile Cu during the application of antifouling paints. In locations where more vessels in maintenance were found, the concentration of Cu-DGT exceeded the PNEC value (0.16 μg.L-1) and represented an important part of the total dissolved fraction (>93 %). The MEC/PNEC quotients, showed that shipyard areas represent a high ecological risk. Thus, it is highlighted the need for site-specific environmental assessments to manage complex ecosystems and set in environmental legislation. Consequently, the novel coupling of DGT technique and the derivation of a site-specific PNEC represent an easily applicable tool as an alternative to classical ERAs.Food and environmental safety issues attributable to the polybrominated diphenyl ethers (PBDEs) are gaining increasing attention, and these urge us to establish a high-performance sample-handling technique. In this study, an outstanding adsorption performance with short adsorption time (10 min) was achieved for PBDEs using a novel synthesized dispersive solid-phase extraction adsorbent, a reticulated covalent organic framework with N/O functional groups (i.e., imine linkage, triazine, and methoxy) (TAPT-DMTA-COF). By conducting sufficient experimentation and theoretical simulation on adsorption mechanism, the halogen bond between electronegative N/O atoms of TAPT-DMTA-COF and the electropositive Br atoms of PBDEs were observed to play a more pivotal role than π-π, C-H…π interactions, and hydrophobic effects. Furthermore, the positive linear relation between calculated adsorption energy and Br content directly clarified that enrichment behavior of PBDEs can be attributed to halogen bonding. These data implied that integrated nanostructure (i.e., N/O functional groups and reticulated architecture) effectively enhanced adsorption capacity. In case of PBDE analysis, this approach achieved excellent results with low limits of detection (0.03-0.13 ng L-1). Finally, the promising potential applications of aforementioned method were verified by spiking water, fish, and milk samples with PBDEs; good PBDEs recoveries were obtained.Soot samples from different fuels were produced in small and pilot combustion test benches at various O2 concentrations, and were then characterized in terms of primary particle diameter, specific surface area and oxygen content/speciation. Water sorption measurements were then carried out for soot compacted into pellet form and in powder form, using both a gravimetric microbalance and a manometric analyser. Water adsorption isotherms are all found to be Type V, and reveal the central role of the specific surface area and the oxygen content of soot. A single parametrization of the second Dubinin-Serpinsky model gives a proper fit for all isotherms. To the best of our knowledge, this is the first study to provide physico-chemical parameters and water sorption results for fire soot. Tipranavir ic50 This enables a better description of the soot cake formed on filters during a fire, in particular in industrial confined facilities as simulated in this study. Humidity can be then explicitly considered in the same way as other parameters influencing the aeraulic resistance of soot cakes.