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Recovering chemical energy embedded in pollutants is significant in achieving carbon-neutral industrial wastewater treatment. Considering that industrial wastewater is usually treated in a decentralized manner, in situutilization of chemical energy to achieve waste-to-treasure should be given priority. Herein, the chemical energy released by the electroreduction of Cr(VI) was used to enhance on-site H2O2generation in a stacked flow-through electrochemical system. The driving force of water flow efficiently coupled O2evolution with 2-e O2reduction to facilitate H2O2generation by transporting anode-produced O2to the cathode. Meanwhile, the chemical energy released by Cr(VI) promoted O2evolution and impeded H2evolution by regulating the electrode potentials, accounting for the enhanced H2O2generation. The system could completely reduce 10–100 ppm of Cr(VI), reaching the maximum H2O2concentration of 2.41 mM. In particular, the H2O2concentrations in the Cr(VI)-containing electrolyte were 10.6–88.1% higher than those in the Cr(VI) free electrolyte at 1.8–2.5 V. A 24-day continuous experiment demonstrated the high efficiency and stability of the system, achieving a 100% reduction efficiency for 100 ppm of Cr(VI) and producing ∼1.5 mM H2O2at 1.8 V. This study presents a feasible strategy for Cr(VI) detoxification and synchronous on-site H2O2generation, providing a new perspective for innovative Cr(VI) wastewater treatment toward resource utilization.

Industrial hypersaline wastewaters contain diverse pollutants that harm the environment. Recovering clean water, alkali and acid from these wastewaters can promote circular economy and environmental protection. However, current electrochemical and advanced oxidation processes, which rely on hydroxyl radicals to degrade organic compounds, are inefficient and energy intensive. Here we report a flow-through redox-neutral electrochemical reactor (FRER) that effectively removes organic contaminants from hypersaline wastewaters via the chlorination–dehalogenation–hydroxylation route involving radical–radical cross-coupling. Bench-scale experiments demonstrate that the FRER achieves over 75% removal of total organic carbon across various compounds, and it maintains decontamination performance for over 360 h and continuously treats real hypersaline wastewaters for two months without corrosion. Integrating the FRER with electrodialysis reduces operating costs by 63.3% and CO2emissions by 82.6% when compared with traditional multi-effect evaporation-crystallization techniques, placing our system at technology readiness levels of 7–8. The desalinated water, high-purity NaOH (>95%) and acid produced offset industrial production activities and thus support global sustainable development objectives.

Solar water evaporation (SWE) has emerged as an appealing method for water and salt recovery from hypersaline wastewater. However, different ions usually transfer and accumulate uncontrollably during ion–water separation, making salt fractionalization impractical for conventional SWE, and the resulting mixed salts are hard to use and still require significant costs for disposal. To achieve salt fractionalization and reutilization, achieving ion–water and ion–ion separation simultaneously are crucial in advancing SWE toward sustainability. Here, we present a wood-derived nanofluidic solar-driven fractional crystallizer that regulates the ion transfer processes and extracts nearly pure salt from a mixture of salts. SWE continuously induces capillary flow to propel and concentrate the ions in the wood channels. Meanwhile, engineered functional groups on the channel walls dominate the ion separation process via differentiated interactions with different ions. During ion transfer through channels, SO42–approaches the channel wall to compete for the positive charges and propels Cl–away, slowing SO42–transport and enlarging the transport energy barrier gap (2.65 to 19.28 kJ mol–1) between SO42–and Cl–. Through in situobservation, positive charges on the channel wall make SO42–lag Cl–12.4 times that of bare Wood-D, accounting for the enhanced ion separation and the consequent fractional salt crystallization.

Introduction: Circular RNAs (CircRNA) have emerged as an interest of research in recent years due to its regulatory role in various kinds of cancers of human body. Esophageal squamous cell carcinoma (ESCC) is one of the major disease subtype in Asian countries, including China. CircRNAs are formed by back-splicing covalently joined 3′- and 5′- ends rather than canonical splicing and are found to have binding affinity with miRNAs that conjointly contribute to oncogenesis. Materials and methods: 4 pairs of normal, cancer adjacent tissues and cancer tissues were analyzed by high-throughput RNA sequencing and 84 differentially upregulated circRNAs were detected in cancer tissues. hsa_circ_0032746 was silenced by siRNA and lentivirus and then further proliferation, migration and invasion were performed by CCK-8 and transwell assays. Bioinformatic analysis  predicted binding affinity of circRNA/miRNA/mRNA axis. Results: After qPCR validation, we selected a novel upregulated hsa_circ_0032746 to explore its biogenetic functions which showed high expression in cancer tissues but not in cancer adjacent tissues. The clinicopathological relation of hsa_circ_0032746 showed positive correlation with the tumor location (P= 0.026) and gender (P= 0.05). We also predicted that hsa_circ_0032746 could sponge with microRNA. Bioinformatic analysis predicted 11 microRNA response element (MRE) sequences of hsa_circ_0032746 and dual luciferase reporter assay confirmed binding affinity with miR4270 evidencing further study of circRNA/miRNA role. The knockdown of hsa_circ_0032746 by siRNA and lentivirus demonstrated that proliferation, invasion and migration of ESCC were inhibited in vitro and vivo experiments. Bioinformatic analysis further predicted MCM3 as a target of miR-4270 and was found upregulated in ESCC upon validation. miR4270 mimic decreased the level of hsa_circ_0032746 and MCM3 while further rescue experiments demonstrated that hsa_circ_0032746 was dependent on miR4270/MCM3 axis on the development process of ESCC. Conclusion: We revealed for the first time that circ_0032746/mir4270/MCM3 contributes in proliferation, migration and invasion of ESCC and could have potential prognostic and therapeutic significance.

Hydroxyl radical (•OH) can hydroxylate or dehydrogenate organics without forming extra products and is thereby expediently applied in extensive domains. Although it can be efficiently produced through single-electron transfer from transition-metal-containing activators to hydrogen peroxide (H2O2), narrow applicable pH range, strict activator/H2O2ratio requirement, and byproducts that are formed in the mixture with the background matrix necessitate the need for additional energy-intensive up/downstream treatments. Here, we show a green Fenton process in an electrochemical cell, where the electro-generated atomic H* on a Pd/graphite cathode enables the efficient conversion of H2O2into •OH and subsequent degradation of organic pollutants (80% efficiency). Operando liquid time-of-fight secondary ion mass spectrometry verified that H2O2activation takes place through a transition state of the Pd–H*–H2O2adduct with a low reaction energy barrier of 0.92 eV, whereby the lone electron in atomic H* can readily cleave the peroxide bridge, with •OH and H2O as products (ΔGr= −1.344 eV). Using H+or H2O as the resource, we demonstrate that the well-directed output of H* determines the pH-independent production of •OH for stable conversion of organic contaminants in wider pH ranges (3–12). The research pioneers a novel path for eliminating the restrictions that are historically challenging in the traditional Fenton process.

The synergetic effect of neighboring heterogeneous atoms is capable of enabling unexpected catalytic performance, and the design of a well-ordered atomic structure and elaborating the underlying interactions are crucial for the development of superior electrocatalysts in fuel cells. We demonstrate here that an ordered Pd–Hg intermetallic alloy with dimensions of several nanometers can be subtly manipulated using a mild wet-chemical reduction approach. On the basis of combined results of XPS and HAADF-STEM analysis, the adjacent regions of metallic atoms were found to be evenly occupied by heterogeneous elements from the distribution features of the surface structure. Due to charge transfer from Hg to neighboring Pd, the down-shift of the d-band center in PdHg alloys was theoretically beneficial for desorption of crucial intermediates (*OH), both in anodic ethanol oxidation reaction (EOR) and in cathodic oxygen reduction reaction (ORR). In the presence of Hg atoms with lower *OH desorption energy, the rapid dissociation of *OH from Pd facilitated the final H2O formation, with superior ORR efficiency comparable to Pt/C catalysts. Remarkably, the rapid combination of *OH on Hg atoms with CH3CO* on neighboring Pd atoms unambiguously favored generation of acetate ions (rate-determining) in the catalytic EOR process, resulting in a high mass activity (7.68 A per mgPd). This well-ordered atomic structure also shows excellent long-term stability in ethylene glycol oxidation reaction and ORR.

Degradation of chlorinated disinfection by-products using the electroreduction process has been considered as a promising approach for advanced water treatment, while the removal efficiency is restricted by a high barrier for dechlorination of intermediates only by reductive atomic hydrogen (H*) and excessive cost required for reducing atmosphere. In this paper, we predict that the dechlorination efficiency for trichloroacetic acid (TCA), a typical chlorinated disinfection by-product, can be accelerated via a synchronous reduction–oxidation process, where the dechlorination barrier can be lowered by the oxidation reactions toward the critical intermediates using hydroxyl radicals (·OH). Based on scientific findings, we constructed a synchronous reduction–oxidation platform using a Pd-loaded Cu/Cu2O/CuO array as the core component. According to the combined results of theoretical and experimental analyses, we found that the high dispersion of nano-sized Pd on a photocathode was beneficial for the production of a high concentration of H* at low overpotential, a perquisite for initiating the dechlorination reaction. Simultaneously, excess H* has the potential to convert O2to H2O2in ambient conditions (air condition), and H2O2can be further activated by a Cu-containing substrate to ·OH for attacking the critical intermediates. In this system, ∼89.1% of TCA was completely dechlorinated and ∼26.8% mineralization was achieved in 60 min, which was in contrast to the value of ∼65.7% and mineralization efficiency of only ∼1.7% achieved through the reduction process (Ar condition).

Surface-adsorbed active species are intermediates with strong activities in heterogeneous catalytic reactions. Effective stabilization of these intermediates is crucial to improve the catalytic performance. Here, we demonstrated highly active bimetallic palladium–indium (Pd–In) nanoparticles (NPs) that can stabilize atomic H* on the surface and show efficient electrocatalytic reduction performance toward bromate. The optimal atomic ratio of Pd to In was investigated with the aim of efficient formation and strong stabilization of H*, thus facilitating the reduction and decontamination of carcinogenic bromate. Pd2In3was the most active catalyst, with a high rate constant of 0.029 min–1, whereas the rate constant for monometallic Pd NPs was only 0.009 min–1. Density functional theory calculations suggest that Pd2In3NPs decrease the work function and provide strong H* stabilization ability. By employing a flow-through electrode coated with Pd2In3NPs to enhance the mass transport, the utilization of H* could be boosted and the reduction kinetics increased up to 7.5 times.

Lanthanum (La)-based materials have been recognized as promising adsorbents for aqueous phosphate removal. The incorporation of base metals into La (oxy)hydroxides represents an effective strategy to improve adsorption performance. Understanding how base metals affect phosphate adsorption is challenging but essential for the development of effective materials for phosphorus control. Herein, we demonstrated a high-performance LaFe (oxy)hydroxide and studied its mechanisms on phosphate adsorption. The P K edge X-ray absorption near edge structure (XANES) analysis showed that PO43–was preferentially bonded with La, and the lattice oxygen in LaFe (oxy)hydroxide was demonstrated to be the active site. The O K edge XANES suggested that Fe optimized the electron structure of La, and Fe/La metal orbital hybridization resulted in the shift of oxygen p character to unoccupied states, facilitating phosphate adsorption. Furthermore, surface analysis showed that the pore size and volume were increased due to the introduction of Fe, which enabled efficient utilization of the active sites and fast adsorption kinetics. The dual effects of Fe in LaFe (oxy)hydroxide greatly enhance the effectiveness of La and represent a new strategy for the development of future phosphorus-control materials.

Utilization of photocatalytic reactions to trigger persistent large-scale reactions could be an alternative path for practical solar energy conversion to relieve environmental pressure nowadays. We took the view that the photoinduction of transition states was critical for improving the activity of catalytic reactions. On the basis of theoretical predictions, the reaction Gibbs free energy of permonosulfate (PMS) activation can be rapidly reduced by molybdenum with low valence. We therefore constructed a multiphasic molybdenum dichalcogenide (MoS2) heterostructure-based photosystem that enabled generation of Mo transition states by visible light excitation. According to combination results of electron paramagnetic resonance, photoelectrochemical analysis, and X-ray photoelectron spectroscopy, we confirmed that the optimized 2H/1T heterojunction permitted the transport of excited interfacial electrons from the semiconductive 2H phase to the metallic 1T phase, and synchronously partially reduced Mo(IV) to Mo(III) at the interface. This intensified the charge transfer between the MoS2and PMS-containing solution, thereby efficiently splitting the PMS molecules into •OH and SO4•–radicals. In this system, a type of refractory herbicide, 2,4-dichlorophenoxyacetic acid (2,4-D), can be degraded within 60 min at a rate constant of 6.20 × 10–2min–1using multiphasic MoS2with a 1T/2H ratio of 1:1.

A N2fixation by the electrocatalytic nitrogen reduction reaction from humidified air is regarded to be a critical tool for producing NH3and reducing the globally accelerating CO2emissions. Notwithstanding great efforts to improve catalyst activity and selectivity, promoting catalyst accessibility to high N2concentrations to ensure that active sites fulfill their function should be a promising design direction. Here, Au nanoparticles are firmly anchored through atomic O on the surface of two-dimensional Ti3C2using an ultrasound reduction process. Akin to the conspicuous role of the web in the predatory process of spiders, N2adsorption experiments primarily suggest that a Ti3C2“web” is beneficial for extraction of N2from air, and embedding high valence-state Au clusters in the Ti3C2“web” strengthens the chemical bonding effect toward N2molecules. The high energy of N2adsorption on the interface between gold clusters and Ti3C2is the driving force for weakening triple N≡N bonds, and thereby the activation energy barrier is lowered via effective stabilization of N2H* species and destabilizing NH2NH2* under an alternative pathway. With Au loading content of ∼0.94%, Au/Ti3C2exhibits an outstanding average yield of 30.06 μg h–1mg–1for NH3production, with a high Faraday efficiency of 18.34% at −0.2 V.

Metallic hydroxides have been applied as the adsorbents of oxyanion contaminants, with the oxygen-bonded metal (M–O) considered as the core site for adsorption. For enhanced adsorption toward oxyanions, multimetallic modification of M–O is a promising approach for high removal performance. Here, bimetallic La/Zr hydroxides were prepared via a solvothermal route with varying La/Zr dosages. Bimetallic La/Zr hydroxides exhibited higher oxyanion adsorption capacity than La or Zr hydroxide. A maximum phosphate adsorption capacity of ∼160 mg g–1was achieved under the La/Zr atomic ratio of 1:1, representing a new record among comparable adsorbents. X-ray photoelectron spectroscopy and X-ray absorption near-edge structure (XANES) spectroscopy showed that the incorporation of [LaO6] and [ZrO6] can induce an internal charge shuttle owing to the electronegativity difference of La and Zr. The charge transfers from La to Zr through the surrounding O 2p ligand, where the electrons in the highest occupied molecular orbitals of the [LaO6] octahedron filled unoccupied π orbitals of [ZrO6]. The as-induced internal electron shuttle in the bimetallic hydroxides primarily strengthened the formation of [MO6]···PO4species (backdonation interaction). Further, the σP–Odonation interaction between [LaO6] and [PO4] was clearly increased via intensification of the covalent coordination with O, as confirmed by the P K-edge XANES spectra for the as-used samples.

Facilitating catalyst accessibility to cleavage of N≡N bond and breakage of competition from hydrogen evolution reaction (HER) remain great challenges in catalytic nitrogen reduction reaction (NRR). By fine confining of oxygen vacancies (OVs) in atomic layered molybdenum oxide (MoO2), we herein reported a sustainable strategy to tackle the rigorous requirements, thereby figuring out the deep-seated mechanism underlying the increment mechanism. X-ray absorption near edge structure (XANES) and Electron Paramagnetic Resonance (EPR) results primarily indicated that vast majority of OVs with different concentrations distributed well on layered MoO2. Based on the combined results of chemical N2adsorption isotherm and DFT calculation, we revealed that OVs favoured chemical adsorption for N2molecular via electron donation on defective Mo, providing the prerequisite for following activation. Remarkably, the energy change calculation unveiled that suitable confined OVs on MoO2NRR followed an novel distal/alternating hybrid path, whereby the energy barrier was effectively lowered after directly protonation of N2H2* to HN2H2* (ΔG = 0.36 eV), so that OVs-MoO2catalyst exhibited a high activity and selectivity with NH3yield rate of ~12.20 μg h−1mg−1and a Faradaic efficiency of 8.2% at a low potential of −0.15 V.

Porous materials constructed from hierarchical pores are beneficial for the mass transport during the aqueous adsorption process. To achieve high performance, it is important to create adequate numbers of active centers to anchor the target ions in the solution. Synchronous construction of powerful bonding sites in the surface area amplification process should be a promising path for developing outstanding sorbents. By in situ evaporation of reductive soft organic templates, we successfully confined oxygen vacancies (VO) in porous La/Zr bimetallic oxides. For aqueous phosphate contaminants, the as-produced porous sorbent exhibited superior removal performance, with equilibrium adsorption capacities almost ∼2 times higher those that of the VO-free counterpart. Based on mass transfer model analysis, pore structure has the potential to buffer external influence on mass transfer. Under an adverse condition (pH 9.0), the mass transfer was ∼2.5 times higher than that in the pore-free one (0.10 min–1vs 0.04 min–1), ensuring the possibility of diffusing phosphate in further contact with these active sites. According to results of orbital interaction analysis and X-ray spectroscopy measurements, VO-dominated active sites not only enhanced attractive orbital bonding interaction toward phosphate but also converted repulsive interaction into attractive reaction, thereby eliminating this kinetics barrier and promoting the rate of phosphate chemisorption reaction.

Solar evaporation is a cost-effective way for obtaining clean water using renewable energy. However, many solar evaporation devices still show unsatisfactory performance and suffer from inefficient utilization of absorbed solar energy. Herein, numerical simulations of solar evaporation demonstrate that the heat management is a key factor governing the solar evaporation efficiency. This prediction is confirmed through using a bilayered solar steam generation architecture [hollow glass microsphere–carbon black (HS–CB)] both in laboratory- and pilot-scale studies. The HS–CB consists of a CB film as a solar-thermal conversion layer and three-dimensional hierarchical polyvinylidene fluoride skeleton cross-linking HSs as a heat localization and water-transporting layer. A balance between thermal insulation and capillary-driven water transport can be reached by tuning the porosity of the thermal-insulating layer, thus inducing optimized heat localization. The proposed structure evaporates water with an efficiency of 82.1% under 1 sun irradiance (1 kW m–2) in the laboratory and can even stably produce 4.63 L m–2d–1(average efficiency of 37%) of purified water from highly concentrated industrial waste water in the pilot study, demonstrating its promising potential for applications in seawater desalination and brackish water purification.

The development of high-performance electrocatalytic systems for the extraction of energy from contaminants in wastewater are urgently needed in emerging renewable energy technologies. However, given that most of the contaminants are present in low concentrations, the heterogeneous catalytic reactions often suffer from slow kinetics due to mass transfer limitations. Here, we report that localized free convection induced by enthalpy change of the reaction can enhance interfacial mass transport. This phenomenon can be found around high-curvature nanosized tips. The finite-element numerical simulation shows that the heat of reactions can produce temperature gradients and subsequently lead to fluid motion at the interfaces, which facilitates the rate-limiting step (mass transfer). To demonstrate the effects of localized field-enhanced mass transport in electrocatalytic conversion of aqueous dilute species, a galvanic cell is constructed with a vertically aligned polyaniline array with sharp tips (as cathode) for the detoxification of a low concentration of carcinogenic chromate and synchronous electricity generation, which show lower overpotential (0.17 V decreased), higher reaction rate (increased by 28%), and power density (22.3 W m–2in 2 mM chromate). The power output can be scaled up (open voltage of ∼3.7 V and volumetric power density of 840.1 W m–3) by using a continuous flow-through cell with stacked electrodes for further improve the mass transport.

Hierarchical three-dimensional architectures of granphene-based materials with tailored microstructure and functionality exhibit unique mass transport behaviors and tunable active sites for various applications. The micro- /nanochannels in the porous structure can act as micro- /nano- reactors, which optimize the transport and conversion of contaminants. However, the size-effects of the micro- /nanochannels, which are directly related to its performance in electrochemical processes, have not been explored. Here, using lamellar-structured graphene films as electrodes, we demonstrate that the interlayer spacing (range from ∼84 nm to ∼2.44 μm) between graphene nanosheets governs the mass transport and electron transfer in electrochemical processes; subsequently influence the water decontamination performances. The microchannel (interlayer spacing = ∼2.44 μm) can provide higher active surface areas, but slow reaction kinetics. Densely packed graphene nanosheets (interlayer spacing = ∼280 nm), which possessed better electron conductivity and could provide higher surface-area-to-volume ratio in narrow nanochannels (7.14 μm–1), achieved the highest reaction kinetics. However, the ion-accessible surface area was decreased in highly dense films (interlayer spacing = ∼84 nm) due to serious interlayer stacking of graphene nanosheets, thereby leading poor reaction kinetics. These results demonstrate the size-effect of nanochannels in porous materials and highlight the importance of controlling mass transport and electron transfer for optimal electrochemical performance, enabling a deep understanding of the benefits and utilization of these hierarchical three-dimensional architectures in water purification.

Atmospheric water harvesting is an emerging strategy for decentralized and potable water supplies. However, water nucleation and microdroplet coalescence on condensing surfaces often result in surface flooding owing to the lack of a sufficient directional driving force for shedding. Herein, inspired by the fascinating properties of lizards and catfish, we present a condensing surface with engineered hydrogel patterns that enable rapid and sustainable water harvesting through the directional pumping and drag-reduced sliding of water droplets. The movement of microscale condensed droplets is synergistically driven by the surface energy gradient and difference in Laplace pressure induced by the arch hydrogel patterns. Meanwhile, the superhydrophilic hydrogel surface can strongly bond inner-layer water molecules to form a lubricant film that reduces drag and facilitates the sliding of droplets off the condensing surface. Thus, this strategy is promising for various water purification techniques based on liquid–vapor phase-change processes.Hydrogel fibers were proposed to integrate merits of lizard and catfish, creating surface energy gradients and Laplace pressure difference to directionally steer the droplets for enhanced atmospheric water harvesting.

Iron (Fe) oxides are the most commonly used adsorbent materials for the aqueous removal of Arsenic (As), but they have deficiencies, including low uptake and poor removal of the relatively higher toxicity As(III). Introduction of transition metals into Fe-containing adsorbents, an inexpensive method of altering Fe chemical states, is likewise of interest for removing As(III) from water by means of adsorption. Porous cubic Fe–Mn structures with BET surface area of 450 m2g–1were herein prepared via chemical etching of Mn-substituted Prussian Blue analogues (PBAs). Cyclic voltammetry showed a “protective” role of polyvinylpyrrolidone (PVP) during the preparation process, so that Mn with high valence state was readily preserved in this binuclear corner-sharing structure. The calculated reaction Gibbs free energy, which was the most negative of the studied adsorbents, indicated that the adsorption was promoted in the presence of high valence Mn. The structures were capable of directly capturing As(III) oxyanions to below the acceptable limits in drinking water standards, and the saturation uptake capacity of 460 mg g–1was substantially higher than comparable materials under consideration. The work therefore presents a new benchmark for As-adsorbent materials and demonstrates the promise of the porous Fe–Mn structure for rapid removal of other metal ions from contaminated water for environmental remediation.

The development of highly efficient energy conversion technologies to extract energy from wastewater is urgently needed, especially in facing of increasing energy and environment burdens. Here, we successfully fabricated a novel hybrid fuel cell with BiOCl-NH4PTA as photocatalyst. The polyoxometalate (NH4PTA) act as the acceptor of photoelectrons and could retard the recombination of photogenerated electrons and holes, which lead to superior photocatalytic degradation. By utilizing BiOCl-NH4PTA as photocatalysts and Pt/C air-cathode, we successfully constructed an electron and mass transfer enhanced photocatalytic hybrid fuel cell with flow-through field (F-HFC). In this novel fuel cell, dyes and biomass could be directly degraded and stable power output could be obtained. About 87 % of dyes could be degraded in 30 min irradiation and nearly 100 % removed within 90 min. The current density could reach up to ∼267.1 µA/cm2; with maximum power density (Pmax) of ∼16.2 µW/cm2with Rhodamine B as organic pollutant in F-HFC. The power densities were 9.0 µW/cm2, 12.2 µW/cm2, and 13.9 µW/cm2when using methyl orange (MO), glucose and starch as substrates, respectively. This hybrid fuel cell with BiOCl-NH4PTA composite fulfills the purpose of decontamination of aqueous organic pollutants and synchronous electricity generation. Moreover, the novel design cell with separated photodegradation unit and the electricity generation unit could bring potential practical application in water purification and energy recovery from wastewater.

Metal ion separation is crucial to environmental decontamination, chromatography, and metal recovery and recycling. Theoretical studies have suggested that the ion distributions in the electric double-layer (EDL) region depend on the nature of the ions and the characteristics of the charged electrode surface. We believe that rational design of the electrode material and device structure will enable EDL-based devices to be utilized in the separation of aqueous metal ions. On the basis of this concept, we fabricate an EDL separation (EDLS) device based on sandwich-structured N-functionalized graphene sheets (CN-GS) for selective separation of aqueous toxic heavy metal ions. We demonstrate that the EDLS enables randomly distributed soluble ions to form a coordination-driven layer and electrostatic-driven layer in the interfacial region of the CN-GS/solution. Through tuning the surface potential of the CN-GS, the effective separation of heavy metal ions (coordination-driven layer) from alkali or alkaline earth metal ions (electrostatic-driven layer) can be achieved.

Talin is an integrin-binding protein located at focal adhesion site and serves as both an adapter and a force transmitter. Its integrin binding activity is regulated by the intramolecular autoinhibition interaction between its F3 and RS domains. Here, we used atomic force microscopy to measure the strength of talin autoinhibition complex. Our results suggest that the lifetime of talin autoinhibition complex shows weak catch bond behavior and does not change significantly at smaller forces, while it drops rapidly at larger forces (>10 pN). Moreover, besides the complex conformation revealed by crystal structure, our molecular dynamics (MD) simulations indicate the possible existence of another stable conformation. Further analysis indicates that forces may regulate the equilibrium of the two stable binding states and result in the non-exponential force dependence of the binding lifetime. Our findings reveal a negative regulation mechanism on talin activation and provide a new point of view on the function of talin in focal adhesion.

A graphite-reduced graphite oxide (rGO) core–sheath structured fiber was synthesized through chemical exfoliation of graphitic carbon fiber. The graphitic carbon fiber was oxidized to form a graphite–graphite oxide core–sheath fiber and followed by thermal exfoliation to form a graphite–rGO core–sheath fiber. The core–sheath fiber with a three-dimensionally (3D) structured rGO sheath possesses a high surface area and pore size around 5.5 nm. A two-electrode supercapacitor constructed with this core–sheath fiber-based paper exhibited a high specific capacitance (140 F g–1at a current density of 1 A g–1), high power density of 45 kW/kg, and good cycling stability (10% capacity loss after 3000 cycles). The surface area normalized capacitance reached as high as 59.4 μF cm–2, indicating the effective use of surface area. The low equivalent series resistance value of 0.45 ohm in the Nyquist plot indicates an extremely small resistance between the graphite core and rGO sheet sheath. The hierarchical three-dimensional structure enables one to maximize the advantages of both graphite and rGO sheets. The 3D-structured rGO sheets sheath with regular pore structure is favorable for ion diffusion due to its interconnected porous system, while the graphite core provides an electron transport pathway with high conductivity.

We have previously shown that the protein kinase A (PKA) inhibitor, 8-chloroadenosine-3′,5′–monophosphorothioate (Rp-8-Cl-cAMPS), abolishes ocular dominance plasticity in the cat visual cortex. Here we investigate the effect of this inhibitor on orientation selectivity. The inhibitor reduces orientation selectivity in monocularly deprived animals but not in normal animals. In other words, PKA inhibitors by themselves do not affect orientation selectivity, nor does monocular deprivation by itself, but monocular deprivation in combination with a PKA inhibitor does affect orientation selectivity. This result is found for the receptive fields in both deprived and nondeprived eyes. Although there is a tendency for the orientation selectivity in the nondeprived eye to be higher than the orientation selectivity in the deprived eye, the orientation selectivity in both eyes is considerably less than normal. The result is striking in animals at 4 wk of age. The effect of the monocular deprivation on orientation selectivity is reduced at 6 wk of age and absent at 9 wk of age, while the effect on ocular dominance shifts is less changed in agreement with previous results showing that the critical period for orientation/direction selectivity ends earlier than the critical period for ocular dominance. We conclude that closure of one eye in combination with inhibition of PKA reduces orientation selectivity during the period that orientation selectivity is still mutable and that the reduction in orientation selectivity is transferred to the nondeprived eye.

Metabotropic glutamate receptors have a variety of effects in visual cortex that depend on the age of the animal, the layer of the cortex, and the group of the receptor. Here we describe these effects for group I receptors, using both in vivo and in vitro preparations. The metabotropic group I glutamate receptor agonist 3,5 dihydroxyphenylglycine (DHPG) potentiates the responses toN-methyl-d-aspartate (NMDA) and α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) in slices of rat visual cortex. It also increases, initially, the visual response in the cat visual cortex. Both these effects are largest at 3–4 wk of age and decline to insignificance by 10 wk of age. Both are also largest in lower layers of cortex, which explains why the facilitatory effects found with the general metabotropic glutamate agonist 1S,3R aminocyclopentane-1,3-dicarboxylic acid (ACPD) are observed only in lower layers. Prolonged application of DHPG in the cat visual cortex, after the initial excitatory effect, produces depression. We also found that DHPG facilitates the NMDA response in fast-spiking cells, which are inhibitory, providing a partial explanation for this. Thus there are multiple effects of group I metabotropic glutamate receptors, which vary with layer and age in visual cortex.

We compared the effect of 2 days of monocular vision on the ocular dominance of cells in the visual cortex of light-reared kittens with the effect in dark-reared kittens at 6, 9, and 14 weeks of age, and analyzed the results by layer. The size of the ocular-dominance shift declined with age in all layers in light-reared animals. There was not a large change in the ocular-dominance shift with age in dark-reared animals in any layer, suggesting that dark rearing largely keeps the cortex in the immature 6-week state until 14 weeks or longer, although there was a slight decrease in layers II, III, and IV, and a slight increase in layers V and VI. At 14 weeks, the difference between light- and dark-reared animals was smallest in layer IV, larger in layers II/III, and largest in layers V/VI, suggesting that dark rearing has a large effect on intracortical synapses and a small effect on geniculocortical synapses. There was a significant ocular-dominance shift in layer IV at 14 weeks of age in both light- animals and dark-reared animals, showing that the critical period for ocular-dominance plasticity is not ended at this age. While the ocular-dominance shift after 26 h of monocular deprivation in 6-week animals was similar in light- and dark-reared animals, after 14 h it was smaller in dark-reared animals, showing that ocular-dominance changes occur more slowly in dark-reared animals at this age, in agreement with Mower (1991). Increases in selectivity for axis of movement after 26 h of monocular vision were seen in dark-reared animals at 6 weeks of age, but not at 9 or 14 weeks of age, showing that the critical period for axial selectivity ends earlier than the critical period for ocular dominance in dark-reared animals, as it does in light-reared animals.

Active chlorine species-mediated electrocatalytic oxidation is a promising strategy for ammonia removal in decentralized wastewater treatment. Flow-through electrodes (FTEs) provide an ideal platform for this strategy because of enhanced mass transport and sufficient electrochemically accessible sites. However, limited insight into spatial distribution of electrochemically accessible sites within FTEs inhibits the improvement of reactor efficiency and the reduction of FTE costs. Herein, a microfluidic-based electrochemical system is developed for the operandoobservation of microspatial reactions within pore channels, which reveals that reactions occur only in the surface layer of the electrode thickness. To further quantify the spatial distribution, finite element simulations demonstrate that over 75.0% of the current is accumulated in the 20.0% thickness of the electrode surface. Based on these findings, a gradient-coated method for the active layer was proposed and applied to a Ti/RuO2porous electrode with an optimized pore diameter of ∼25 μm, whose electrochemically accessible surface area was 381.7 times that of the planar electrode while alleviating bubble entrapment. The optimized reactor enables complete ammonia removal with an energy consumption of 60.4 kWh kg–1N, which was 24.2% and 39.9% less than those with pore diameters of ∼3 μm and ∼90 μm, respectively.

Herein, a natural deep eutectic solvent (DES) is developed to deconstruct the recalcitrant structure of sugarcane bagasse (SCB) for further 5‐hydroxymethylfurfural (5‐HMF) production. The properties, structure of the DES, and the influence of pretreatment and reaction conditions on SCB are studied. The findings reveal that carboxylic acid DES pretreatment results in a substantial decrease of hemicelluloses and lignin. At the same time, carboxylic acid DES systems significantly improve the yield of 5‐HMF at 110 °C. Under the optimum conditions (choline chloride (ChCl)–lactic acid (8.33 wt% H2O), SCB/DES (1:10/wt:wt), temperature 110 °C, and time 4 h), the 5‐HMF yield obtained from SCB is 56.68 mol% (1.62 mg mL−1). This 5‐HMF yield is significantly higher by 25.88, 16.43, and 9.87‐folds compared to the 5‐HMF yield from the SCB treated with ChCl–urea, ChCl–glycerin, and ChCl–ethylene glycol, respectively, under the same reaction conditions. In addition, component analysis and structural characteristics suggest that the content of lignin in the SCB decreases significantly, and the cellulose and hemicellulose are partially hydrolyzed after being treated with the DES composed of ChCl and carboxylic acids. Overall, this work shows that SCB pretreatment with a carboxylic acid DES is promising for low‐cost biorefineries to achieve effective biomass fractionation and conversion. Seven kinds of deep eutectic solvents (DESs) are prepared and used for pretreatment and transformation of sugarcane bagasse (SCB). The synthetic DESs are characterized by a series of analyses. The results show that the DESs can deconstruct the SCB structure by removing lignin so that 5‐HMF can be effectively obtained from SCB after pretreatment with a DES.

A ternary green solvent γ‐valerolactone (GVL)/choline chloride (ChCl)/H2O system is used to convert rice waste to hydroxymethylfurfural (HMF) using AlCl3·6H2O as a catalyst. The effect of the reaction time, temperature, substrate, catalyst, and catalyst amount on the extraction of HMF by GVL is studied under this system. The results show that in ChCl/H2O, GVL/H2O, and GVL/ChCl/H2O systems, the HMF yield reaches the highest levels of 8.21, 12.24, and 18.60 mol% after reaction at 140 °C for 1 h, respectively. The yield of HMF obtained by reacting 0.42 mmof AlCl3·6H2O at 140 °C for 30 min is significantly higher than that of CrCl3·6H2O and FeCl3·6H2O. After reaction at 140 °C for 5 min, the extraction rate of HMF by GVL reaches more than 80%. The aqueous solution of ChCl forming the ternary system has high recyclability, and after six times, the yield loss of HMF is small. A ternary green solvent γ‐valerolactone (GVL)/choline chloride (ChCl)/H2O system is used to convert rice waste to hydroxymethylfurfural (HMF) using AlCl3•6H2O as a catalyst. The effect of the reaction time, temperature, substrate, catalyst, and catalyst amount on the extraction of HMF by GVL is studied under this system. This system may be a new and green method of HMF production.

A template approach for the synthesis of porous cobalt phosphide nanoarrays (Co2P/CoP NAs) is reported, which exhibits superior electrocatalytic activity and stability toward charge storage and hydrogen evolution.Using Co2P/CoP NAs as a charge mediator, the H2and O2evolution of alkaline water electrolysis is separated effectively in time, thereby achieving a membrane-free pathway for H2purification.Introduction of easily oxidized chemicals to replace water oxidation triggers a low energy consumption path toward H2purification.