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Abstract: Ice templates have been widely used for controlled assembly of nanoparticles into well‐defined 3D superstructures. However, ultrathin 2D nanofilms, which are highly desirable for wearable smart nanodevices, are seldom reported to be prepared via conventional ice‐templated assembly method. In this work, ultrathin AuAg nanofilms are successfully prepared by a simple ice‐templated assembly method from ultrathin AuAg nanowires (NWs). The ice/liquid interface is proposed as a unique platform facilitating the self‐assembly of NWs into monolayer nanofilms. Benefiting from the polymer‐like property of ultrathin AuAg NWs, the obtained ultrathin AuAg nanofilms exhibit high flexibility and excellent stability. The AuAg nanofilms prepared on the flexible polyethylene terephthalate substrate retain high transparency and conductivity under harsh environments and upon strong deformations. The nonspecific ice/liquid interfacial assembly can be further extended to prepare other ultrathin nanofilms made of various inorganic ultrathin NWs. [ABSTRACT FROM AUTHOR]

The analysis of time-series concentrations (C TS) is of great importance when investigating the biogeochemical processes of nutrients in aquatic environments. However, obtaining C TS of nutrients remains a challenge using current sampling techniques. In this study, a novel in situ sampler was constructed using reverse osmosis membrane (ROM) osmotic pumps (OP) (ROM-OP sampler), and was used to obtain the C TS of nutrients in surface waters. The sampler consisted of a sampling OP, sample storing coil, filter, bubble injection module, and preservative adding module. When deployed, the sampling OP continuously draws ambient water through the filter into the sample storing coil, while simultaneously the preservative adding module continuously delivers preservative (H 2 SO 4 solution) into the water flow. The bubble injection module periodically injects air bubbles into the sample storing coil, to segment the sample and create time stamp indicators that allow the sample age to be defined. Upon retrieval, the sample segments in the coil are sequentially pumped out of the sample storing coil and transferred into different vials for further analysis. The sampler was applied to measure the C TS of various nutrients, including dissolved total nitrogen, dissolved total phosphorus, dissolved reactive phosphorus, and nitrate in a river over a 20 day period and in municipal sewage treatment plant effluent for a 36 h period. Results showed that the ROM-OP sampler successfully obtained C TS of nutrients, capturing nutrient variations at a high temporal resolution. This sampler is relatively low-cost (~USD 300), small in size, lightweight, robust and does not require an external power source, showing high promise as an effective and efficient tool for monitoring nutrient C TS in aquatic environments. Unlabelled Image • Time-series sampler developed using osmotic pumps with reverse osmosis membrane. • Air bubbles were used to segment the water sample, with H 2 SO 4 as a preservative. • Obtained a high temporal resolution time-series of nutrient concentrations. • Excellent agreement was achieved between sampler-collected samples and spot samples. • The sampler is cheap, small size, robust and requires no external power source. [ABSTRACT FROM AUTHOR]