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Flexible wearable electronics were developed for applications such as electronic skins, human-machine interactions, healthcare monitoring, and anti-infection therapy. But conventional materials showed impermeability, single sensing ability, and no designated therapy, which hindered their applications. Thus it was still a great challenge to develop electronic devices with multifunctional sensing properties and self-driven anti-infection therapy. Herein, flexible and breathable on-skin electronic devices for multifunctional fabric based sensing and self-driven designated anti-infection therapy were prepared successfully with cellulose nanocrystals/iron(III) ion/polyvinyl alcohol (CNC/Fe3+/PVA) composite. The resultant composite films possessed robust mechanical performances, outstanding conductivity, and distinguished breathability (3.03 kg/(m2·d)), which benefited from the multiple interactions of weak hydrogen bonds and Fe3+ chelation and synergistic effects among CNC, polyaniline (PANI), and PVA. Surprisingly, the film could be assembled as a multifunctional sensor to actively monitor real-time physical and infection related signals such as temperature, moisture, pH, NH3, and human movements even at sweat states. More importantly, this multifunctional device could act as a self-driven therapist to eliminate bacterial by the release of Fe3+, which was driven by the damage of metal coordination Fe-O bonds due to the high temperature caused by infection at wound sites. Thus, the composite films had potential versatile applications in electronic skins, smart wound dressings, human-machine interactions, and self-driven anti-infection therapy.

A fundamental challenge in nanomaterial science is to facilely fabricate nonspherical polymersomes. Here, several kinds of novel tubular polymersomes were fabricated via self-assembly of amphiphilic azobenzene-containing block copolymers. Besides, their shape could be tuned by multiple approaches including changes in the chemical structure, self-assembly conditions and external stimuli.

The effect of two widely distributed macrophytes, reed and cattail, on phosphorus fractionations (PFs) of surface sediments distributions from a near-nature constructed wetland were studied in both autumn and spring. The results showed that the average values of PFs in the sediments were ranked in the order of Ca-P > Org-P > Al-P ≈ Fe-P > Ex-P > O-P. The mobile PFs, such as Al-P, Fe-P, Ex-P and Org-P influenced the TP concentrations in macrophytes free area. Only Ca-P was related with TP in macrophytes covered area, indicating the P stability of reed community sediment (RCS) and cattail community sediment (CCS). The other compositions of sediments, i.e. organic matter (OM), alkaline phosphatase activity (APA), and active-Fe were greatly decreased in the presence of macrophytes, while active-Al were slightly increased. OM and active-Al were found to be more significant related with PFs in OWS and RCS, while APA and active-Fe were related with PFs in the macrophytes covered sediments. Therefore, macrophytes induced the variation of sediment compositions and further influenced the distributions and stabilization of PFs. Moreover, cattail community performed better in declining the sediment compositions, P accumulation and its release.

Electronic skins are developed for applications such as biomedical sensors, robotic prosthetics, and human-machine interactions, which raise the interest in composite materials that possess both flexibility and sensing properties. Polypyrrole-coated cellulose nanocrystals and cellulose nanofibers were prepared using iron(III) chloride (FeCl3) oxidant, which were used to reinforce polyvinyl alcohol (PVA). The combination of weak H-bonds and iron coordination bonds and the synergistic effect of these components yielded self-healing nanocomposite films with robust mechanical strength (409% increase compared to pure PVA and high toughness up to 407.1%) and excellent adhesion (9670 times greater than its own weight) to various substrates in air and water. When damaged, the nanocomposite films displayed good mechanical (72.0-76.3%) and conductive (54.9-91.2%) recovery after a healing time of 30 min. More importantly, the flexible nanocomposites possessed high strain sensitivity under subtle strains (

Water level fluctuation and inorganic nitrogen enrichment are two serious problems caused by anthropogenic disturbances in aquatic ecosystems. They cause resource fluctuation and thus might influence the invasive-ness of alien plants. Alternanthera philoxeroides is an amphibious and widespread clonal plant which exhibits significant invasiveness. This experimental study examined the plant's morphological traits under different nitrogen concentrations and water levels. The responses of A. philoxeroides to water levels and nitrogen concentrations were similar for both land-like and riverbank-like initial conditions. A. philoxeroides showed an escape strategy of shoot elongation when its growth was suppressed by shallow submergence. No toxic symptoms but increased clonal spread was observed at high nitrogen concentrations, suggesting that A. philoxeroides not only tolerated but benefitted from nitrogen-polluted water. High nitrogen level mitigated the negative effects of submergence on its leaf survival, thereby enhancing its adaptation to water level fluctuation. Such strong adaptability and clonal spread helps A. philoxeroides to grow and invade successfully in shallow eutrophic water.

Burial characteristics and risks associated with 13 organochlorine pesticides (OCPs; α-HCH, β-HCH, γ-HCH, δ-HCH, p,p′-DDE, p,p′-DDD, p,p′-DDT, heptachlor, aldrin, dieldrin, endrin, α-endosulfan and β-endosulfan) in core sediments of Lake Baiyangdian were investigated. The core sediments were taken from areas of different anthropogenic activity along the lake. Concentrations of hexachlorocyclohexane (HCH), dichlorodiphenyltrichloroethane (DDT), heptachlor, aldrin, and endosulfan ranged from 0.64 to 2.72, nd (undetectable levels) to 2.79, 0.29 to 1.37, nd to 2.62, and nd to 1.76 ng g−1, respectively. Concentrations of OCPs in the core sediments exhibited the following spatial trend: Dongtianzhuang > Shaochedian > Zaolinzhuang. Concentrations in the surficial layer were also found to be greater than those in the bottom layer. OCPs were dominated by HCH. β-HCH was found in the greatest concentrations, indicating that the majority of HCH came from older inputs to the area. The ratio of DDT and its metabolites (DDD and DDE) also suggested a lack of recent inputs to the lake environment. The residues of heptachlor, aldrin, and endosulfan in core sediments indicated that cyclodienes were historically applied in the area. The OCP risk assessment, which was based on effect range low and threshold effect level values, suggested that the top layer of sediment in Dongtianzhuang cores had a relatively high toxicity to human health and the environment.