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Abstract Constructing nanolaminate membranes made of two-dimensional graphene oxide nanosheets has gained enormous interest in recent decades. However, a key challenge facing current graphene-based membranes is their poor rejection for monovalent salts due to the swelling-induced weak nanoconfinement and the transmembrane co-transport of anions and cations. Herein, we propose a strategy of electrostatic-induced ion-confined partitioning in a reduced graphene oxide membrane for breaking the correlation of anions and cations to suppress anion-cation co-transport, substantially improving the desalination performance. The membrane demonstrates a rejection of 95.5% for NaCl with a water permeance of 48.6 L m−2 h−1 bar−1 in pressure-driven process, and it also exhibits a salt rejection of 99.7% and a water flux of 47.0 L m−2 h−1 under osmosis-driven condition, outperforming the performance of reported graphene-based membranes. The simulation and calculation results unveil that the strong electrostatic attraction of membrane forces the hydrated Na+ to undergo dehydration and be exclusively confined in the nanochannels, strengthening the intra-nanochannel anion/cation partitioning, which refrains from the dynamical anion-cation correlations and thereby prevents anions and cations from co-transporting through the membrane. This study provides guidance for designing advanced desalination membranes and inspires the future development of membrane-based separation technologies.

Direct hydrogen peroxide electrosynthesis offers a sustainable alternative to the traditional energy-intensive anthraquinone technology. Here, the authors report a scalable cobalt single-site catalyst for hydrogen peroxide synthesis at industrial-relevant currents in acidic, neutral or alkaline electrolyte.

The development of highly water-permeable membranes is key for the treatment of high salinity waters. Here the authors enhance the water permeability of a metal-organic framework nanoporous membrane via an intra-crystalline defect engineering strategy.

Efficient electroreduction of CO2 to multi-carbon products is challenging. Here, the single atom Cu encapsulated on N-doped porous carbon catalysts are designed for reducing CO2 to acetone at low overpotentials and the active sites are identified as Cu coordination with four pyrrole-N atoms.

Objective To investigate the the timing of the first time of hyperbaric oxygen therapy and its effect on the recovery of neurological function and quality of life in patients with acute moderate to severe carbon monoxide poisoning. Methods A retrospective analysis was carried out in the patients with acute carbon monoxide poisoning admitted to our hyperbaric oxygen treatment center from January 2015 to June 2018. The patients who met the criteria of poisoning within 24 h, did not receive hyperbaric oxygen treatment in other hospitals, and had moderate or severe poisoning were divided into 3 groups according to the first treatment time, that is, ultra-early group (shorter than 6 h after poisoning), early group (within 6~12 h), and ordinary group (in 12~24 h after poisoning). The degree of recovery (complete recovery, partial recovery, no recovery), Glasgow coma index (GCS), simple mental state scale (MMSE), Barthel index (BI) and incidence of delayed encephalopathy after treatment was compared among the 3 groups. Results A total of 136 patients were eligible for admission, including 39 in the ultra-early group, 51 in the early group and 46 in the ordinary group. There were no significant differences in age, sex distribution and total treatment times among the groups. At the end of treatment, the proportions of patients with complete recovery were 43.5%, 31.4%, and 17.4%, respectively in the ultra-early group, early group and ordinary group. The improvement of GCS score was 4.85, 3.87 and 3.01, respectively, that of MMSE score was 19.01, 14.05, and 12.34, respectively, and that of BI was 75.48, 68.24 and 54.58, respectively, in the 3 groups. In 1 year after the treatment, delayed encephalopathy was observed in 2 cases (5.1%) in the ultra-early group, 7 cases (13.7%) in the early group, and 14 cases (30.4%) in the ordinary group. The ultra-early group obtained all better indicators than the ordinary group, and better percentage of complete recovery of symptoms, MMSE score and lower incidence of delayed encephalopathy when compared with the early group (all P < 0.05). Conclusion Implementation of hyperbaric oxygen therapy within 6 h after poisoning can result in a better prognosis for patients with moderate to severe acute carbon monoxide poisoning.

Electro-Fenton in neutral medium has attracted more and more attention since it can relieve the costs of H2O2 storage and pH adjustment, which are the major disadvantages limiting the practical applications of Fenton reaction. The electrode with good performance for electrochemical H2O2 production from O2 in neutral medium is of great importance in electro-Fenton. Herein, the N-doped three-dimensional carbon foam (NCF) electrode was obtained by using melamine foam as precursor. The nitrogen functional groups and graphitization degree could be tailored by adjusting the carbonization temperature. NCF1000, the sample carbonized at 1,000 °C, presents the H2O2 selectivity of 81.9%, which is the highest among those of other NCFs. The H2O2 concentration in neutral medium on NCF1000 achieved 0.87 mmol L−1 at −0.6 V, which is 1.8, 2 and 2.6 times as much as those on graphite, carbon cloth and carbon felt. Using as cathode in electro-Fenton, NCF1000 exhibits the kinetic rate of 0.062 min−1 for phenol degradation, which is 4.1 times larger than that on graphite electrode. As well, the performance of NCF1000 shows no visible attenuation after ten times phenol removal experiments, demonstrating its good reusability. These results indicate the potential of NCF as a promising alternative for commercial carbon-based electrode in electro-Fenton.

Abstract Photocatalytic membranes that driven by visible light are highly desired for water treatment. Here g-C3N4 quantum dots (QDs) assembled into TiO2 nanotube array (TNA) membranes were fabricated for the first time as a visible-light-driven g-C3N4/TNA membrane. Benefiting from the synergistic effect of membrane filtration and photocatalysis, more than 60% of rhodamine B could be removed from water under visible light irradiation. Meanwhile, the g-C3N4/TNA membrane presented an enhanced anti-fouling ability during filtering water containing Escherichia coli under visible light irradiation, and a permeate flux of 2 times higher than that of filtration alone was obtained by integrated process. This study offers a promising strategy for the potential application of the visible-light-driven membranes in water treatment.

Low concentrations of pollutants in surface water challenge the assessment of chronic effects on human health. Human bone mesenchymal stem cells (hBMSCs) were employed as a sensitive and relevant in vitro model to evaluate the potential biological effects caused by mixtures of pollutants in surface water. Organic extracts of surface water collected from Hun River inhibited cell viability in a dose-dependent manner. Surface water extracts at noncytotoxic concentrations induced 533 to 1055 differentially expressed genes (DEGs) in hBMSCs after 48 h of exposure. Total of 370 genes were commonly affected by surface water from different sites and accounted for 35–69% of DEGs impaired by individual sample. Pathways related to human diseases, genetic information processing and organismal systems were enriched based on DEGs. Interleukins (IL1B, IL6 and IL8) were affected and involved in most human diseases related pathways. The significantly downregulation of COL1A1 and the variation of rheumatoid arthritis pathway suggested that surface water potentially inhibited osteogenic differentiation of hBMSCs. Clustering analysis and principle component analysis with DEGs distinguish the surface water from tributary and mainstream. The crossing-species comparison of transcriptomic changes identified 923 and 2715 differentially expressed orthologs in hBMSCs and zebrafish, respectively. After the exposure ceased, the followed osteogenic and adipogenic differentiation in hBMSCs for 14 days were inhibited by the treatment of surface water during undifferentiated period, whereas the non-polar fraction exhibited stronger potency in affecting differentiation than the mid to polar fractions. hBMSCs, combining unsupervised transcriptomic technique and specific endpoints test, are promising in screening the health effects of environmental mixtures in surface water. Keywords: Human bone mesenchymal stem cell, Surface water, Microarray, Cross species, Differentiation

Recently a novel sliver oxide Ag3AsO4 has been found to be an excellent photocatalyst with strong oxidation capability for pollutant degradation under visible light. But the origin of its high visible light photocatalytic activity was unclear which hindered further research of Ag3AsO4. For clarifying that, the electronic structure and optical properties of Ag3AsO4 have been analyzed by the hybrid density functional method. The results reveal that the Ag3AsO4 presents a narrow band gap with strong oxidation ability of the valence bands maximum edge and the highly delocalized charge distribution of the conduction bands minimum is beneficial for the carriers transfer to surface to participate in the photocatalytic reaction. These results provide clear explanations of the excellent visible light photocatalytic performance of the Ag3AsO4 from microscopic aspect. And it is significant to design novel materials with high photocatalytic performance.

MoS2/CdS photocatalyst was fabricated by a hydrothermal method for H2 production under visible light. This method used low toxic thiourea as a sulfur source and was carried out at 200°C. Thus, it was better than the traditional methods, which are based on an annealing process at relatively high temperature (above 400°C) using toxic H2S as reducing agent. Scanning electron microscopy and transmission electron microscopy images showed that the morphologies of MoS2/CdS samples were feather shaped and MoS2 layer was on the surface of CdS. The X-ray photoelectron spectroscopy testified that the sample was composed of stoichiometric MoS2 and CdS. The UV-vis diffuse reflectance spectra displayed that the loading of MoS2 can enhance the optical absorption of MoS2/CdS. The photocatalytic activity of MoS2/CdS was evaluated by producing hydrogen. The hydrogen production rate on MoS2/CdS reached 192 μmol·h−1. This performance was stable during three repeated photocatalytic processes.