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This study aims to investigate the potential nanotoxic effects of TiO2 nanoparticles (TNPs) to dams and pups during lactation period. TiO2 nanoparticles are accumulated in mammary glands of lactating mice after i.v. administration. This accumulation of TiO2 NP likely causes a ROS-induced disruption of tight junction of the blood-milk barrier as indicated by the loss of tight junction proteins and the shedding of alveolar epithelial cells. Compared to larger TNPs (50 nm), smaller ones (8 nm) exhibit a higher accumulation in mammary glands and are more potent in causing perturbations to blood-milk barrier. An alarming finding is that the smaller TNPs (8 nm) are transferred from dams to pups through breastfeeding, likely through the disrupted blood-milk barrier. However, during the lactation period, the nutrient quality of milk from dams and the early developmental landmarks of the pups are not affected by above perturbations. [ABSTRACT FROM AUTHOR]

• Seasonal variation pattern of evapotranspiration of Platycladus orientalis. • Comparing the differences between the evapotranspiration and liquid flow methods. • The accuracy of lyismeter method is more stable than that of sap-flow method. A comprehensive understanding of the changing patterns and the contribution of each component of the forest ecosystem to evapotranspiration is necessary for an accurate assessment of biological quality, terrestrial ecosystem production, energy exchange, and water use efficiency. In this study, two methods (i.e., the sap-flow and lysimeter methods) were used to partition evapotranspiration (ET) into evaporation(E) and transpiration(T) components using stable isotope techniques. The factors affecting the contribution of T to ET (F T) were evaluated. The results showed that F T presents seasonal variation patterns throughout the year. Both methods accurately simulated the ET partitioning and its seasonal variation. The ET value estimated by the sap-flow method was less than that estimated by the lysimeter method. In contrast, the simulated value of T calculated using the lysimeter method was higher than that calculated by the sap-flow method. However, this was within allowable limits. The lysimeter method is more accurate and suitable for monitoring forest ecosystem evapotranspiration in practical experiments. This study provides a technical reference for the optimal calculation method of ET partitioning using a stable isotope-based technique. It provides baseline information to better understand water vapour exchange in forest ecosystems in China. [ABSTRACT FROM AUTHOR]

Lanthanide-doped TiO2 nanoparticles (La-TiO2NP)-modified electrode was successfully prepared by the sol-gel and dip-coating methods on the indium tin oxide electrode. Scanning electron microscopy, X-ray photoelectron spectroscopy, X-ray diffraction, and photoluminescence spectra were used to characterize its structure and composition. The degradation efficiency of methyl orange could be increased by 26.17% with the La-TiO2NP-modified electrode compared with that using the pure TiO2NP-modified electrode under applied voltage of 0.3 V with illumination. The as-prepared electrode also exhibited good repeatability and reproducibility. © 2012 American Institute of Chemical Engineers Environ Prog, 32: 302-306, 2013 [ABSTRACT FROM AUTHOR]

Abstract: Pt nanoparticles decorated TiO2 nanotubes (Pt/TiO2NTs) modified electrode has been successfully synthesized by depositing Pt in TiO2NTs, which were prepared by anodization of the Ti foil. Scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), and electrochemical methods were adopted to characterize their structures and properties. The Pt/TiO2NTs electrode shows excellent electrocatalytic activity toward methanol oxidation reaction (MOR) in alkaline electrolyte without UV irradiation. [Copyright &y& Elsevier]

Inhomogeneous plastic deformation and recrystallization behavior of Mg-Gd-Y-Zn-Zr alloy containing only intragranular lamellar long-period stacking ordered (LPSO) phase were investigated by isothermal compression experiments at the temperatures of 350–450 °C, and the strain rates of 0.001 ∼ 10 s−1. Results showed that Mg-Gd-Y-Zn-Zr alloys with varying degrees of bimodal structures were obtained after compression. The lamellar LPSO phase directions in residual coarse grains were aligned in the radial direction (RD). Dynamic recrystallization (DRX) grains induced at grain boundaries, kinked bands, and lamellar shearing regions during compression synergistically promoted coarse grain refinement. Moreover, the condition of high temperature and medium strain rate (450 °C-0.1 s−1) contributed to the uniform extension of "mantle layers" of fine DRX grains. In contrast, the condition of medium temperature and high strain rate (400 °C-10 s−1) could accelerate the deflection of CD-directed (compression direction) LPSO lamellae and the formation of local high-energy regions, facilitating the generation of recrystallization band. In addition, a high strain rate (400 °C-10 s−1) is more conducive to the formation of a heavily bimodal structure than a high temperature (450 °C-0.1 s−1). Only a larger spacing of LPSO lamellae (∼1.4 μm) could meet the spatial requirements of recrystallization. Further analysis revealed that the continuous dynamic recrystallization (CDRX) mechanism characterized by the expansion of "mantle layers" and nucleation along kinked boundaries and lamellar shearing regions was the primary grain refinement mechanism. The discontinuous dynamic recrystallization (DDRX) mechanism only exhibited a limited role due to the inhibition of the highly dense lamellar LPSO phase on grain boundaries bulging. After compression, the orientation of residual coarse grains gradually deviated toward the CD. While the recrystallization with limited proportion and random orientation cannot significantly weaken the basal texture. [Display omitted] • Highly densely packed LPSO-phase lamellae were constructed through homogenization treatment. • The DRX behavior affected by the exclusively lamellar LPSO-phase was revealed. • Increasing the strain rate was more conducive to fostering recrystallization than raising the temperature. • A bimodal structure was obtained due to the local microstructural refinement caused by partial recrystallization. • The CDRX mechanism, rather than the DDRX mechanism, dominated the compression process. [ABSTRACT FROM AUTHOR]

[Display omitted] In this study, leveraging the tunable surface groups of MXene, the two-dimensional (2D) Nb 2 C T x with OH terminal (NC) was synthesized. 2D ZnIn 2 S 4 (ZIS) nanosheets were prepared with the aid of sodium citrate, enhancing the exposure ratio of active (1 1 0) facet. On this basis, 2D/2D ZnIn 2 S 4 /Nb 2 C T x heterojunctions were fabricated to improve photocatalytic hydrogen evolution reaction (HER) performance. The optimized 6 wt%Nb 2 C T x /ZnIn 2 S 4 -450 (6NC/ZIS-450) photocatalyt exhibits a remarkable HER rate of 3603 μmol g−1h−1, which is 10 times superior to that of the original ZnIn 2 S 4. Its apparent quantum efficiency (AQE) at 380 nm reaches 14.9 %. Meanwhile, even after 5 rounds of HER, the activity of 2D/2D ZnIn 2 S 4 /Nb 2 C T x heterojunction remained at 90 %, far superior to that of pure ZnIn 2 S 4 (34 % and 31 %). Energy band structure analysis and density functional theory (DFT) calculation indicate that Nb 2 C T x adsorbed with OH exhibit a low work function. By serving as a hole cocatalyst, it effectively boosts the photocatalytic HER rate of ZnIn 2 S 4 /Nb 2 C T x heterojunction and inhibits the photocorrosion of ZnIn 2 S 4. This unique insight, via hole transport highways and increased exposure of active facets, effectively enhances the activity and stability of sulfides photocatalysts. [ABSTRACT FROM AUTHOR]

The authors report that CuOx/NiOy hollow nanocomposites are an effective bifunctional catalyst capable of oxidizing glucose and reducing hydrogen peroxide. Synthesis is based on a solvothermal process and subsequent thermal treatment. The structure can be controlled by adjusting the amounts of added NiCl2 during the solvothermal etching process, and core-shell, yolk-shell or hollow structures can be obtained. The porous hollow structure composite of type CuO30/NiO90 was used to modify a glassy carbon electrode. It exhibits excellent electrocatalytic activity towards glucose oxidation in solution of pH 13, typically at a working potential of +0.60 V (vs. Ag/AgCl). This enables voltammetric sensing of glucose with (a) a low limit of detection (0.08 μM, at S/N = 3), (b) over a wide linear range (0.20 μM - 2.5 mM), and (c) high sensitivity (2043 μA·mM−1·cm−2). The sensor is reproducible, selective and stable. It can be used to detect glucose in spiked human serum. The CuO30/NiO90 composite also displays good electrocatalytic activity towards reduction of H2O2 in neutral aqueous medium, typically at an applied potential of −0.35 V. It has a detection limit of 90 nM, a sensitivity of 271.1 μA·mM−1·cm−2, and a linear detection range that extends from 0.30 μM to 9.0 mM.CuOx/NiOy nanocomposites with three different structures were synthesized by coordinated etching precipitation method. The hollow structure CuO30/NiO90 was coated on the surface of glassy carbon electrode for the amperometric determination of glucose and hydrogen peroxide. [ABSTRACT FROM AUTHOR]

A Fe-Co dual-metal co-doped N containing the carbon composite (FeCo-HNC) was prepared by adjusting the ratio of iron to cobalt as well as the pyrolysis temperature with the assistance of functionalized silica template. Fe1Co-HNC, which was formed with 1D carbon nanotubes and 2D carbon nanosheets including a rich mesoporous structure, exhibited outstanding oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) catalytic activities. The ORR half-wave potential is 0.86 V (vs. reversible hydrogen electrode, RHE), and the OER overpotential is 0.76 V at 10 mA cm−2 with the Fe1Co-HNC catalyst. It also displayed superior performance in zinc–air batteries. This method provides a promising strategy for the fabrication of efficient transition metal-based carbon catalysts. [ABSTRACT FROM AUTHOR]

[Display omitted] In this work, potassium acetate (KAc) was added during the synthesis of a Zn-Fe based metal-organic framework (Fe-ZIF-8) to increase the fixed amount of Fe while simultaneously enhancing the number of pores. Electrospinning was utilized to embed KAc-modified Fe-ZIF-8 (Fe-ZIF-8-Ac) into the polyacrylonitrile nanofiber mesh, to obtain a network composite (Fe@NC-Ac) with hierarchical porous structure. Fe@NC-Ac was co-pyrolyzed with thiourea, resulting in Fe, N, S co-doped carbon electrocatalyst. The electrochemical tests indicated that the prepared catalyst displayed relatively remarkable oxygen reduction reaction (ORR) catalytic activity, with an onset potential (E onset) of 1.08 V (vs. reversible hydrogen electrode, RHE) and a half-wave potential (E 1/2) of 0.94 V, both higher than those of the commercial Pt/C (E onset = 0.95 V and E 1/2 = 0.84 V), respectively. Assembled into Zn-air batteries, the optimized catalyst exhibited higher open circuit voltage (1.698 V) and peak power density (90 mW cm−2) than those of the commercial 20 wt% Pt/C (1.402 V and 80 mW cm−2), respectively. This work provided a straightforward manufacturing strategy for the design of hierarchical porous carbon-based ORR catalysts with desirable performance. [ABSTRACT FROM AUTHOR]

The conventional synthesis route of graphene oxide (GOG), based on Hummers method, suffers from explosion risk, environmental concerns and a tedious synthesis process, which increases production costs and hinders its practical applications. Herein, we report a novel strategy for preparing few-layer graphene oxide (GOH) from humic acid via simple hydrothermal treatment. The formation of GOH is mainly attributed to the hydrolysis, oxidation and aromatization of humic acid under hydrothermal conditions. The as-prepared few-layer GOH has typical morphology (thin and crumpled sheets with the thickness of ~3.2 nm), crystal structure (a Raman ID/IG ratio of 1.09) and chemical composition (an X-ray Photoelectron Spectroscopy (XPS) O/C atomic ratio of 0.36) of few-layer GOG. The thermally reduced GOH (r-GOH) delivers considerable area capacitance of 28 µF·cm−2, high rate capability and low electrochemical resistance as supercapacitor electrodes. The described hydrothermal process shows great promise for the cheap, green and efficient synthesis of few-layer graphene oxide for advanced applications. [ABSTRACT FROM AUTHOR]

Intelligent membranes with adaptive gating channels play a crucial role in cellular functions and separation processes. This study introduces a novel approach to controlling channel expansion using biomimetic adaptive aggregates, fundamentally overcoming the drawbacks of existing methods relying on intertwined polyelectrolyte chains for channel blockage. Specifically, a pH‐responsive 2D material membrane is constructed through the self‐assembling of protein‐mimetic zwitterionic polydopamine (ZPDA) soft molecular aggregates within graphene oxide (GO) interlayers. Similar to the conformational switch of inserted proteins in cellular membranes, the embedded ZPDA in GO nanofluidic channels undergoes an adaptive conformational transformation in response to pH changes. This dynamic adjustment of ZPDA physicochemical properties allows for reversible regulation of GO nanofluidic channel size and charge by external pH modulation. The resulting GO/ZPDA membrane exhibits programmable separation performance for dye molecules (i.e., water permeance of 18.8–35.4 L m−2 h−1 bar−1 and molecular selectivity of 73.7–32.9) and salt ions (i.e., ionic permeance of 0.69–1.25 mol m−2 h−1 and ionic selectivity of 20.8–21.9). This work sheds new light on the engineering of intelligent stimuli‐responsive 2D nanofluidic channels with adaptive gating properties, holding promise across a wide range of applications including separation, drug delivery, sensing, and catalysis. [ABSTRACT FROM AUTHOR]

The excellent physicochemical properties of two-dimensional transition-metal dichalcogenides (2D TMDCs) such as WS2 and WSe2 provide potential benefits for biomedical applications, such as drug delivery, photothermal therapy, and bioimaging. WS2 and WSe2 have recently been used as chemosensitizers; however, the detailed molecular basis underlying WS2- and WSe2-induced sensitization remains elusive. Our recent findings showed that 2D TMDCs with different thicknesses and different element compositions induced autophagy in normal human bronchial epithelial cells and mouse alveolar macrophages at sublethal concentrations. Here, we explored the mechanism by which WS2 and WSe2 act as sensitizers to increase lung cancer cell susceptibility to chemotherapeutic agents. The results showed that WS2 and WSe2 enhanced autophagy flux in A549 lung cancer cells at sublethal concentrations without causing significant cell death. Through the autophagy-specific RT2 Profiler PCR Array, we identified the genes significantly affected by WS2 and WSe2 treatment. Furthermore, the key genes that play central roles in regulating autophagy were identified by constructing a molecular interaction network. A mechanism investigation uncovered that WS2 and WSe2 activated autophagy-related signaling pathways by interacting with different cell surface proteins or cytoplasmic proteins. By utilizing this mechanism, the efficacy of the chemotherapeutic agent doxorubicin was enhanced by WS2 and WSe2 pre-treatment in A549 lung cancer cells. This study revealed a feature of WS2 and WSe2 in cancer therapy, in which they eliminate the resistance of A549 lung cancer cells against doxorubicin, at least partially, by inducing autophagy. [ABSTRACT FROM AUTHOR]

• Non-lethal WS 2 , WSe 2 , NbS 2 and NbSe 2 induced comparable autophagy in MH-S cells. • The four TMDCs activated autophagy pathways in an outer chalcogen-dependent manner. • Extensive endosomal escape only occurred for WSe 2 and NbSe 2 nanosheets. • Perturbation of autophagy sensitized the MH-S cells to respirable benzo[a]pyrene. Increasing risks of incidental and occupational exposures to two-dimensional transition metal dichalcogenides (2D TMDCs) due to their broad application in various areas raised their public health concerns. While the composition-dependent cytotoxicity of 2D TMDCs has been well-recognized, how the outer chalcogenide atoms and inner transition metal atoms differentially contribute to their perturbation on cell homeostasis at non-lethal doses remains to be identified. In the present work, we compared the autophagy induction and related mechanisms in response to WS 2 , NbS 2 , WSe 2 and NbSe 2 nanosheets exposures in MH-S murine alveolar macrophages. All these 2D TMDCs had comparable physicochemical properties, overall cytotoxicity and capability in triggering autophagy in MH-S cells, but showed outer chalcogen-dependent subcellular localization and activation of autophagy pathways. Specifically, WS 2 and NbS 2 nanosheets adhered on the cell surface and internalized in the lysosomes, and triggered mTOR-dependent activation of autophagy. Meanwhile, WSe 2 and NbSe 2 nanosheets had extensive distribution in cytoplasm of MH-S cells and induced autophagy in an mTOR-independent manner. Furthermore, the 2D TMDCs-induced perturbation on autophagy aggravated the cytotoxicity of respirable benzo[a]pyrene. These findings provide a deeper insight into the potential health risk of environmental 2D TMDCs from the perspective of homeostasis perturbation. [Display omitted] [ABSTRACT FROM AUTHOR]

Abstract Abnormal lysosomal pH values have been associated with cellular dysfunctions and many diseases. However, tools to monitor dynamic changes of pH values in live-cell lysosomes are limited. Herein, biocompatible near-infrared (NIR) fluorescent dyes HAN1 - 4 for lysosome-targeting staining were rationally designed and synthesized with the aid of a spiropyran in situ switching (SIS) strategy. The novel SIS-based dyes share the following special characteristics: 1) pH-dependent ratiometric fluorescent patterns matched nicely with pH windows of lysosomes, 2) light-independent real-time spiropyran in situ switching behavior in lysosomes and 3) pH-sensitive fluorescence in the NIR region, thereby ensuring their applications in obtaining highly specific images of live-cell lysosomes with a weak background signal. Among them, the HAN2 probe was found to induce the best ratiometric response toward pH in the range corresponding to lysosomal pH window, thus being further applied for the real-time tracking of lysosomal subtle pH changes in stressed cells undergoing drug and heat stimulations. Live-cell super-resolution and confocal fluorescent imaging indicate that our SIS-based NIR probes are robust and can be applied for the accurate detection of lysosomal pH in complex biosystems. Graphical abstract A ratiometric near-infrared fluorescence strategy based on spiropyran in situ switching for tracking dynamic changes of lysosomal pH is proposed. Image 1 Highlights • Lysosome-targetable fluorescent probes HAN1 - 4 were developed based on a spiropyran in situ switching strategy. • Probe HAN2 displays a desirable ratiometric near-infrared fluorescence response for H+ over biological species. • Probe HAN2 can be applied for real-time tracking dynamic changes of live-cell lysosomal pH. [ABSTRACT FROM AUTHOR]

The article reports on the electrochemical performance of electron cyclotron resonance (ECR) carbon film particularly when detecting biomolecules. An ultra-flat carbon film electrode consisting of sp² and sp³ mixed bonds was developed using the ECR sputtered carbon film. Each base in the oligonucleotides can be measured by applying the film.

Hydraulic fracturing is widely recognized as a potential stimulation technology for the development of challenging natural gas hydrate. However, the fracturing behavior of non-diagenetic hydrate reservoirs has peculiar characteristics that are different from those of conventional oil and gas reservoirs. Herein, a fully coupled fluid-mechanical model for simulating hydraulic fracturing in hydrate-bearing sediments (HBS) was established based on the discrete element method, and the influence of hydrate saturation, in situ stress, and injection rate on the meso-fracture evolution was investigated. The results indicate that with the increase in hydrate saturation, the fracture morphology transitions from bi-wing to multi-branch, thereby enhancing fracture complexity. Both tensile and shear failure modes exist, and the tensile failure between the weakly cemented sediment particles is dominant. The tensile strength of HBS is an exponential function of hydrate saturation, with the breakdown pressure being governed by hydrate saturation and in situ stress, with the form being consistent with the classical Kirsch equation. Additionally, lower in situ stress and higher injection rates are conducive to the generation of microcracks, whereas an excessive injection rate reduces the fracture length. These findings contribute to understanding the meso-evolution mechanism of hydraulic fractures and guide the design of on-site hydraulic fracturing plans of natural gas hydrate reservoirs. [ABSTRACT FROM AUTHOR]

Thixotropic compression tests were carried out on a repetitive upsetting-extrusion (RUE) processed AZ91D magnesium alloy at temperatures ranging from 500 °C to 550 °C by using a Gleeble-1500 thermal-mechanical simulator. Semi-solid stress-strain data were obtained. A modified constitutive model was established to describe the thixotropic behavior of the RUE strained alloys. The results revealed that three stages of elastic-like deformation, strain hardening deformation and rheological viscoplastic deformation were involved in the thixoforming process. Furthermore, the compressed microstructures in semi-solid state were investigated with referring to microstructure observation. Dominant deformation mechanisms during the thixotropic compression were considered as the slipping or rotating mechanism of the solid particles along the liquid films, the slipping mechanism between the solid particles, the plastic deformation mechanism of the solid particles and the DRX behavior of the solid particles, whose function varied with the change of temperature and strain rate. [ABSTRACT FROM AUTHOR]

[Display omitted] • FeCo-NC was prepared by the gel self-limiting method. • 320-Fe 1 Co 1.5 -NC-800 has high specific surface area and mesoporous structure. • The potential difference between ORR and OER was 0.72 V. Exploring efficient noble-metal-free electrocatalysts for the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) is crucial for the development of rechargeable Zn-air batteries. Herein, a self-limiting method using an agarose gel was proposed to prepare bimetallic (iron and cobalt) nitrogen-doped carbon composites (FeCo-NC). The resulting FeCo-NC catalyst has a high surface area and a hierarchical porous structure. The optimized FeCo-NC electrocatalyst exhibits a small potential difference (ΔE) = 0.72 V between the ORR half-wave potential and the OER potential at a current density of 10 mA cm−2 in alkaline media. Impressively, the FeCo-NC Zn-air battery exhibits a high open-circuit voltage, large power density, and outstanding charge–discharge cycling stability. This study provides an effective means of designing electrocatalysts and energy conversion systems. [ABSTRACT FROM AUTHOR]

[Display omitted] • Fe 3 O 4 @rGO composite was rationally designed and in-situ synthetized. • Coupled architecture fully takes advantages of Fe 3 O 4 and rGO to overcome their instinct challenges. • Improved ionic kinetics, electric conductions and electrode stabilizations were achieved. • Unique synergism of Fe 3 O 4 and rGO creates favorable heterogeneous interfaces. Developing advanced electrode materials with appropriate compositions and exquisite configurations is crucial in fabricating lithium-ion batteries (LIBs) with high energy density and fast charging capability plateau. Herein, a Fe 3 O 4 @reduced graphene oxide (Fe 3 O 4 @rGO) coupled architecture was rationally designed and in-situ synthesized. Monodispersed mesoporous Fe 3 O 4 nanospheres were homogeneously formed and strongly bound on interconnected macroporous rGO frameworks to form well-defined three-dimensional (3D) hierarchical porous morphologies. This tailored Fe 3 O 4 @rGO coupled architecture fully exploited the advantages of Fe 3 O 4 and rGO to overcome their inherent challenges, including spontaneous aggregating/excessive restacking tendency, sluggish ions diffusion/electrons transportation, and severe volume expansion/structural collapse. Benefitting from their synergistic effects, the optimized Fe 3 O 4 @rGO composite electrode exhibited an improved electrochemical reactivity, electrical conductivity, electrolyte accessibility, and structural stability. The optimized composite electrode displayed a high specific capacity of 1296.8 mA h g−1 at 0.1 A g−1 after 100 cycles, even retaining 555.1 mA h g−1 at 2 A g−1 after 2000 cycles. The electrochemical kinetics analysis revealed the predominantly pseudocapacitive behaviors of the Fe 3 O 4 @rGO heterogeneous interfaces, accounting for the excellent electrode performance. This study proposes a viable strategy for use in engineering hybrid composites with coupled architectures to optimize their potential as high-performance electrode materials for use in LIBs. [ABSTRACT FROM AUTHOR]

A low-cost dual-chamber microbial fuel cell (MFC) was constructed as a biosensor for the rapid determination of biochemical oxygen demand (BOD) in domestic sewage. The operating conditions were optimized during the operation of the MFCs. The changes in the microbial community structure in the anode compartment were analyzed by 16S rRNA gene sequencing technology. The results indicated that the MFCs-BOD biosensor reached a steady state (maximum voltage of around 550 mV) within 1 week. The optimal working conditions were K3[Fe(CN)6] of 50 mm, anolyte pH of 7, and external resistance of 1000 Ω. The maximum current density and highest power density can be as high as 221.88 mA/m2 and 78.77 mW/m2, respectively. Compared with other studies, the start-up period of this MFCs-BOD biosensor was shorter (96–192 h), the determination range was wider (50–500 mg/L), and the determination time was short (within 3 h). The MFCs-BOD biosensor can accurately determine the BOD content of sewage water samples. The results of 16S rRNA gene sequencing showed that the anodic microbial community after the domestication changed significantly compared with the original inoculated anaerobic activated sludge flora, and the dominant electrogenic bacteria with the highest relative abundance belonged to Proteobacteria and Enterobacteria. The device has reliability and applicability in the BOD determination in actual domestic sewage, and this study provides a solid foundation for the future application of MFCs-BOD biosensor in the rapid determination of BOD in sewage. [ABSTRACT FROM AUTHOR]

The possible detrimental effects of nanomaterials on organisms have become a public concern because of the wide applications of nanomaterials in modern society. This study investigates the effects of silica nanoparticles (nano‐SiO2) on zebrafish development. Fluorescent nano‐SiO2 (FITC‐nano‐SiO2) is synthesized with an emission wavelength of 517 nm. Due to similar hydrodynamic size, FITC‐nano‐SiO2 is used to simulate the distribution of nano‐SiO2 in zebrafish. Nano‐SiO2 regulated col2a1a, col9a2, lect1, and her12 to delay liver development and regulated prox, wnt2bb, mypt1, and hhex caused spinal curvature. The hand2, mef2a, nkx2.5, and atp1a2a are significantly down‐regulated. The whole embryo in situ hybridization revealed amhc and flk1 are also down‐regulated. This suggests that nano‐SiO2 affected heart and blood vessels development of zebrafish. Furthermore, it is found that cell apoptosis occurred in the heart. The proapoptotic genes (bax, bid) are upregulated, and the antiapoptotic genes (bcl‐2, mcl‐1b) are down‐regulated. Nano‐SiO2 increases the endoplasmic reticulum (ER) stress‐related genes (chop, bip, perk, elF2α), indicating that the ER stress is involved in cell apoptosis. This study provides a toxicological basis for evaluating the possible hazards of nano‐SiO2 to aquatic organisms. [ABSTRACT FROM AUTHOR]

• Spent graphite was purified by pre-oxidation coupled with acid leaching process. • Purified graphite was successfully modified via surface carbon-coating method. • The surface-modified graphite possesses favorable core–shell microstructures. • Surface-modified graphite as an anode shows superior lithium storage properties. The recycling of spent lithium-ion batteries (LIBs) has become an increasingly prominent issue along with the widespread application of new energy vehicles, in which the recycling of spent graphite anode material present considerable practical value and research significance. In this work, the spent graphite was purified by pre-oxidation and acid leaching process to obtain purified graphite with industrial grade, and then surface-modified graphite was further synthesized via surface carbon-coating method by using phenol–formaldehyde resin and coal tar pitch as the carbon source, respectively. Surface-modified graphite displays the irregular core–shell structure with the graphite as the core and the amorphous carbons as shell materials. The residual metal and organic impurities on the surface of graphite removed effectively, resulting in the Li+ embedding/embedding channels being repaired, thus improving the efficient Li+ storage. The amorphous carbon layer coating the graphite surface repairs surface defects and safeguards the graphite structure, while also featuring a grid-like arrangement that enhances electron transport. Additionally, it possesses open nanopores that facilitate the efficient insertion and extraction of Li+ into and out of the graphite core. Benefit from the structure, the surface-modified graphite coated with coal tar pitch as anode for LIB delivers a superior reversible capacity (441 mAh·g−1 at current density of 50 mA·g−1) with the initial Coulomb efficiency of 81 %, an excellent cycle performance (462 mAh·g−1 at current density of 100 mA·g−1), and an outstanding cycling stability with a capacity retention of 95 % after 200 cycles at current density of 100 mA·g−1. This work provides an operative and feasible route for the purification of spent graphite, and develops a valuable outlet for the reuse of spent graphite in LIBs. [ABSTRACT FROM AUTHOR]

Membrane-based ion sieving is critical to green desalination processes such as sustainable ionic resource extraction. Two-dimensional (2D) graphene oxide (GO) membranes exhibit unique ionic transport properties owning to the supernormal enhancement of channel effects induced by diverse functional regions under nanoconfinement. However, the discrete and random distribution of the hydrophilic/hydrophobic and positively/negatively charged regions restricts the GO membrane to give full play to its potential in selective ions separation. Herein, a novel strategy is proposed to engineer the asymmetric three-tier architecture of a Janus GO membrane with rational allocation of functional regions. The wise series connection of ① surface positively charged hydrophilic layer of PEI, ② intermediate negatively charged hydrophilic layer of GO and ③ bottom hydrophobic porous layer of rGO along the cross-membrane direction established internal gradients of structure, wetting and charge, resulting in reinforced exclusion of retained divalent ions and reduced stagnation of targeted monovalent ions. Based on the continuous anisotropic gradients, the Janus GO membrane was endowed with the unique capability to act as a unidirectional ion valve system, showcasing impressive permeation performance of monovalent ions permeation rate of 0.244 mol m−2 h−1 with monovalent/divalent ions selectivity of 66.1, and remarkable nanofiltration performance of divalent salt rejections of >96.5 % with monovalent/divalent ions separation factor up to 70.9. The implications of this work will revolutionize the regulation and functionalization of 2D nanofluidic channels for selective ions transport, which is highly desirable for a wide range of green desalination applications. [ABSTRACT FROM AUTHOR]

• The aromatic ring fragments are exfoliated from lignite through mild oxidation. • SCNSs are constructed using ice template-induced assembly strategy. • The obtained SCNSs possess an ultrathin lamella with a large transverse size. • SCNSs have a specific surface area with a rich hierarchical porous architecture. • SCNSs as anodes for LIBs demonstrate satisfactory lithium storage performances. Two-dimensional (2D) porous carbon nanosheets with heteroatom doping are promising anode materials for lithium-ion batteries (LIBs) due to their distinctive sheet-like structure and excellent electrical conductivity. Limited by high preparation costs and cumbersome preparation processes, the large-scale production of carbon nanosheets remains a major challenge. Herein, a series of sulfur-doped porous carbon nanosheets (SCNSs) are successfully synthesized through ice template-induced assembly coupled with a carbonization approach using aromatic ring fragments exfoliating from lignite as the precursor and K 2 SO 4 as the sulfur source. The prepared SCNSs exhibit well-defined sheet-like structures, abundant hierarchical nanopores, large specific surface areas (∼1761 m2·g−1), and high sulfur doping contents (∼7.72 at%). Such unique microstructure characteristics of SCNSs not only provide favorable and efficient channels for the lithium-ions/electrons transportation but also offer sufficient available space or active sites for lithium-ions storage. When used as anode materials for LIBs, the SCNS-3 shows high reversible capacity (1620 mAh·g−1 at 0.05 A·g−1), excellent rate performance (315 mAh·g−1 at 2 A·g−1), and superior cycling stability (901 mAh·g−1 at 1 A·g−1 after 500 cycles). Lithium storage behavior analysis indicated that the capacitance enhancement in SCNSs anodes is primarily due to improved capacitive behavior. This study provides a novel and effective route for the large-scale production of sulfur-doped carbon nanosheets using aromatic ring fragments exfoliated from lignite, which demonstrates promising industrial application potential in LIBs anode materials. [ABSTRACT FROM AUTHOR]

• Fenton oxidation is developed for selective dissolution of AgNPs. • Protein corona-induced extraction was proposed for preconcentration of Ag 2 S-NPs. • An ultrahigh enrichment factor of 10,000 was obtained for Ag 2 S-NPs. • The Ag 2 S-NPs extracted can remain in intact by means of the developed method. • Recoveries of 83.7−105% from real waters can be achieved for low-level Ag 2 S-NPs. Sulfidation of silver nanoparticles (AgNPs) to generate silver sulfide nanoparticles (Ag 2 S-NPs) significantly influences their fate and toxicity in natural environments. However, the correlational research in this field was limited by the lack of methods for speciation analysis of Ag 2 S-NPs. To address this challenge, a novel protocol for the selective Ag 2 S-NP extraction from real waters was developed using protein corona-induced extraction coupled to Fenton oxidation of AgNPs with Fe3+/H 2 O 2 reagents. The ability of various concentrations of Fe3+/H 2 O 2 to selectively dissociate AgNPs into ions was first evaluated. Then, selective separation and preconcentration of the remaining Ag 2 S-NPs was established by optimizing the parameters that may affect the protein corona-induced extraction efficiency, followed by quantification with inductively coupled plasma mass spectrometry (ICP-MS), enabling an ultrahigh enrichment factor of 10,000 and extremely low detection limit (LOD) of 1.8 ng/L. The presence of humic acid (HA), inorganic salts and particles at the environmentally relevant levels had limited effects on Ag 2 S-NP extraction. As demonstrated by transmission electron microscopy (TEM) analysis and single particle ICP-MS (spICP-MS), the sizes, shapes, and compositions of Ag 2 S-NPs extracted with the proposed method remain in intact. Good recoveries of 83.7−105% were achieved for the Ag 2 S-NPs spiked in four natural waters at the level of 97.8 ng/L. Due to the high yields and applicability to Ag 2 S-NPs at environmentally relevant concentrations, this proposed method is particularly suitable to track the generation and transformation of Ag 2 S-NPs in various scenarios. [Display omitted] [ABSTRACT FROM AUTHOR]

Environmental bisphenol F (BPF) has a cyclic endocrine disruption effect, seriously threatening animal and human health. It is frequently detected in environmental samples worldwide. For BPF remediation, biological methods are more environmentally friendly than physicochemical methods. White-rot fungi have been increasingly studied due to their potential capability to degrade environmental pollutants. Phanerochaete sordida YK-624 has been shown to degrade BPF by ligninolytic enzymes under ligninolytic conditions. In the present study, degradation of BPF under non-ligninolytic conditions (no production of ligninolytic enzymes) was investigated. Our results showed that BPF could be completely removed after 7-d incubation. A metabolite of BPF, 4,4'-dihydroxybenzophenone (DHBP) was identified by mass spectrometry and nuclear magnetic resonance, and DHBP was further degraded by this fungus to form 4-hydroxyphenyl 4-hydroxybenzoate (HPHB). DHBP and HPHB were the intermediate metabolites of BPF and would be further degraded by P. sordida YK-624. We also found that cytochrome P450s played an important role in BPF degradation. Additionally, transcriptomic analysis further supported the involvement of these enzymes in the action of BPF degradation. Therefore, BPF is transformed to DHBP and then to HPHB likely oxidized by cytochrome P450s in P. sordida YK-624. Furthermore, the toxicological studies demonstrated that the order of endocrine-disrupting activity for BPF and its metabolites was HPHB > BPF > DHBP. Key points: • White-rot fungus Phanerochaete sordida YK-624 could degrade BPF. • Cytochrome P450s were involved in the BPF degradation. • The order of endocrine disrupting activity was: HPHB > BPF > DHBP. [ABSTRACT FROM AUTHOR]