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Developing efficient, low-cost and bifunctional catalysts with predominant durability for the hydrogen evolution reaction (HER) and the oxygen evolution reaction (OER) is an extraordinary challenge in the preparation of green hydrogen energy by electrochemical water splitting. Three-dimensional (3D) transition metal compounds have become a research hotspot as OER electrocatalysts, which can replace noble metal oxides such as RuO 2 and IrO 2 to reduce application costs. Herein, we synthesized a novel three-dimensional pine-tree-like bimetallic sulfide arrays on nickel foam (FeCoS/NF) using various optimization strategies such as morphology optimization, in situ growth and introduction of heterogeneous structures. The as-synthesized FeCoS/NF electrocatalyst only requires relatively low overpotential of 156 mV to achieve a current density of 20 mA cm−2 for OER, with a Tafel slope of only 37 mV dec−1. It also has a small charge transfer resistance, an electrochemical surface area and good electrochemical stability in alkaline electrolytes. The excellent performance of FeCoS/NF can be attributed to the synergistic effect and amorphous phase of FeCoS as well as the well-defined pine-tree-like array architecture with a large surface area, abundant active sites, and sufficient gas and electrolyte diffusion channels. [Display omitted] • A 3D pine-tree-like structure of FeCoS/NF electrocatalyst was synthesized. • The FeCoS/NF exhibits excellent electrocatalytic activity for OER. • FeCoS/NF-based zinc-air battery shows an open-circuit voltage of 1.27 V. [ABSTRACT FROM AUTHOR]

The design of low-cost, short time, mass preparation and high-efficiency of electrocatalysts for hydrogen evolution reaction (HER), oxygen evolution reaction (OER) and zinc air batteries are highly challenging. Herein, we design a bifunctional chrysanthemum-like electrocatalysts (Cu(OH) 2 @CoMoO 4 ·0.9H 2 O/CF) for highly efficient electrochemical water splitting by a simple and highly controllable two-step method in a few hours. This unique hierarchical electrocatalyst has porous structure and short diffusion paths, which can promote charge transfer, ion and water diffusion, and rapidly release hydrogen and oxygen bubbles. The obtained Cu(OH) 2 @CoMoO 4 ·0.9H 2 O/CF composite exhibits low overpotentials of 57 mV at −10 mA cm−2 toward the HER, which is superior to most of the previously reported CoMoO 4 -based electrocatalysts. And the Cu(OH) 2 @CoMoO 4 ·0.9H 2 O/CF exhibits excellent performance of 355 mV at 100 mA cm−2 toward the OER. Benefiting from the unique hierarchical heterostructure and the coupling effect between the inner and outer layers, the Cu(OH) 2 @CoMoO 4 ·0.9H 2 O/CF catalysts were endowed with high activity for water splitting. [Display omitted] [ABSTRACT FROM AUTHOR]

Developing a high-efficiency, stable and inexpensive bifunctional electrocatalyst/photocatalyst for hydrogen evolution reaction (HER) with suitable Gibbs free energy of hydrogen and rich electron transport channels remains a significant challenge. Herein, noble-metal-free Co nanoparticles decorated CePO 4 nanowires Co/CePO 4 were synthesized using Co-BTC/CePO 4 as a precursor via hydrothermal and calcination methods. A robust coupling heterostructure interface can be generated through carefully designed routes between Co nanoparticles and CePO 4 nanowires. In the HER process, the heterostructure interface can promote the composite catalysts conductivity, increase the active sites, charge-transfer efficiency, and adjust the desorption energy of hydrogen, thus enhancing their HER activity. Benefited from its specific structure, the obtained Co/0.1CePO 4 catalyst exhibits splendid electrocatalytic HER performance with an overpotential of only − 108 mV at − 10 mA cm−2 and a low Tafel slope of 85 mV decade−1, which is superior to many reported noble-metal-free catalysts. Especially, Co/0.1CePO 4 catalysts show an overpotential close to commercial 20 wt % Pt/C (−377 mV vs −340 mV) at a high current density of − 200 mA cm−2. Co/0.1CePO 4 catalyst also exhibits excellent photocatalytic hydrogen production rate (~87.5 μmol h−1) when working with organic photosensitizer Eosin Y. Furthermore, the Co/0.1CePO 4 catalyst reveals favorable stability in both electrocatalytic and photocatalytic HER. This research provides a new insight for fabricate efficient and stable composite HER catalysts. [Display omitted] • Composite of CePO 4 with Co as electro/photo-catalytic HER catalyst is reported. • Co/0.1CePO 4 exhibits excellent electrocatalytic HER performance with the overpotential of − 377 mV close to Pt/C (−340 mV) at high current density 200 mA cm−2. • Co/0.1CePO 4 shows superb photocatalytic HER performance with H 2 generation rate of 87.5 μmol h−1 when sensitized with Eosin-Y. • Mechanism of electro/photo-catalytic HER over Co/CePO 4 catalyst is proposed. [ABSTRACT FROM AUTHOR]

The design and synthesis of high-performance catalysts for hydrogen evolution reaction (HER) is of significant importance for electrocatalysis reaction. In this study, 0D Ag nanoparticles were successfully loaded onto 2D Ni(OH)2 nanosheets by a one-step hydrothermal method for enhancing the electrocatalytic ability. The special structure of Ni(OH)2 with only 2 wt% Ag on 3D nickel foam (NF) exhibited a high surface area and excellent charge transfer channels. Furthermore, the synergistic effect as well as the transfer of electron density between Ag and Ni(OH)2 contributed to a high HER activity. As a result, Ni(OH)2–Ag/NF exhibited excellent HER performance with an overpotential of 89 mV to obtain a current of 10 mA cm−2 in an alkaline electrolyte, 155 mV lower than that of Ni(OH)2/NF. After 10 hours of stability test and more than 1000 cycles, negligible loss of the initial catalytic activity to drive a current density of 10 mA cm−2 verified excellent stability during the alkaline HER process. This research provides a new idea to integrally construct ultralow noble metal catalysts with outstanding HER performance and results in new advances in the field of hydrogen evolution. [ABSTRACT FROM AUTHOR]

Few-layer and 1T-rich MoS2 is synthesized by a one-step solvothermal process using a rigid segment-containing polysulfide as a concomitant sulfur source and in situ intercalator. The prepared MoS2 displays superior hydrogen evolution reaction activity, providing a facile and mild approach for the development of high performing MoS2 and other two-dimensional lamellar materials. [ABSTRACT FROM AUTHOR]

Metal‐organic frameworks (MOFs) have been considered as promising platforms for preparing the efficient oxygen evolution reaction (OER) catalysts, but few of them are directly employed as active components due to their poor electrical conductivity. Herein, a lamellar bimetallic MFN (MIL‐53(FeNi)) encapsulated in graphene aerogel‐grafted Ni foam has been developed (denoted as MFN@GA/NF). The graphene aerogel (GA) provides abundant space for the in‐situ growth of MFN and functions as a "bridge" to connect nickel foam (NF) with MFN by virtue of good conductivity. Benefitting from its structural integrity, the obtained hierarchical MFN@GA/NF exhibited excellent OER performances in alkaline media with an overpotential of 250 mV (20 mA cm−2) and 326 mV (200 mA cm−2), as well as remarkable stability in continuous electrolysis for over 100 h. This work provides a new channel for engineering MOF‐based functional materials with featured architectures. [ABSTRACT FROM AUTHOR]

The fabrication of cost‐effective and performance‐advanced electrocatalysts is in great requirements for water splitting to achieve sustainable oxygen production. A simple and effective precursor of ZIF‐67 particles mounted on Cu(OH)2 nanorods was induced by a template alignment method. After annealing, hierarchical CoO polyhedron‐decorated CuO/Cu2O (CuOx) nanorods on Cu foam (denoted as CuOx@CoO NRs/CF) were achieved, which displayed the heterojunction in CuOx components, hierarchical configuration and outward active sites. These features, verified by HRTEM, SEM, XPS and EDX, optimized the oxygen evolution reaction (OER) electrocatalyst. Benefiting from its large electrochemical surface area and the synergetic effect between CuOx and CoO, CuOx@CoO NRs/CF exhibited considerable catalytic activity with a low overpotential of 254 mV to obtain a current density of 10 mA cm−2 in alkaline electrolyte and a scarce loss of the initial catalyst activity over 24 h and over 5000 cycles. This work provides a channel to enhance the performance in OER. [ABSTRACT FROM AUTHOR]

• A peroxidase-like artificial enzyme with elevated catalysis capacity has been achieved. • The down-sized Fe 3 O 4 nanoparticles were dispersed throughout the urchin-like MnO 2 burrs. • The defect in structure as well as the synergistic effect would allow extra enzyme ability. • The limit of detection for glucose was estimated to be 0.75 μmol L−1. In order to lower the limit of detection of glucose, a peroxidase-like artificial enzyme with elevated catalysis capacity has been achieved. Fe 3 O 4 -doped MnO 2 microspheres were fabricated through a two-step hydrothermal method for this purpose. TEM revealed that down-sized Fe 3 O 4 nanoparticles were dispersed throughout the urchin-like MnO 2 burrs. An additional XRD peak beyond Fe 3 O 4 and MnO 2 nanoparticles was observed, indicating a dislocation structure was formed. The defect in structure as well as the synergistic effect would allow extra enzyme ability. Based on the steady-state kinetic analyses and Michaelis–Menten model, the Michaelis–Menten constants (K m and v max) were figured out. The results showed that the Fe 3 O 4 –MnO 2 composite has elevated affinity toward the substrate TMB and H 2 O 2. The limit of detection for glucose was estimated to be 0.75 μmol L−1 based on the Fe 3 O 4 –MnO 2 composite artificial enzyme. The superparamagnetic properties endowed the material easy separation. The composite of this structure will provide a highly sensitive candidate method for accurate detection of glucose. [ABSTRACT FROM AUTHOR]

In order to develop efficient and earth-abundant catalysts for large-scale hydrogen evolution via water splitting, a Ni/Ni(OH)2 dual composition electrocatalyst was manufactured via a two-step electrodeposition procedure. The stepwise fabricated 3D hierarchical nanoarrays as well as the concurrent dual composition electrodeposition yielded a papillae-like hybrid crystal structure. The high electrochemically active surface area, defect-rich hybrid crystal structure, and synergistic effects of the dual composition provided an elevated catalytic performance. Only 53 mV overpotential was needed to deliver a current density of 10 mA cm−2 with a small Tafel slope of 54.5 mV dec−1 to catalyze the HER in alkaline media. Approximately 81% catalytic activity could be maintained after 20 h of continuous testing, demonstrating long-term stability. Our findings offer an efficient approach to design and fabricate efficient noble-metal-free alkaline HER electrocatalysts. [ABSTRACT FROM AUTHOR]

The fabrication of non‐noble element electrocatalysts with comparable catalytic activity with Pt‐based materials is in great requirements for water splitting to achieve sustainable hydrogen production. Cu2S/MoS2 heterojunction nanorod arrays on copper foam were prepared for this purpose. The nitrogen doping was achieved in situ. HRTEM, SEM, XPS and EDX verified the heterojunction interfacial texture and the defect‐rich nanoarray configuration. The heterojunction interfacial texture, the defect rich configuration and the outward active sites optimized the structure required as a high‐efficient hydrogen evolution reaction (HER) electrocatalyst. As a result, the charge transfer resistance of the nanoarrays was estimated to be 5.4 Ω at −200 mV versus RHE, even lower than both the precursors. The electrochemical double layer capacitance was 49.95 mF cm−2, which was higher than both the precursors. The Cu2S/MoS2 heterojunction nanoarrays‐like electrocatalyst exhibited significant performance with a low overpotential (91 mV at 10 mA cm−2) and a small Tafel slope (41 mV dec−1) in alkaline electrolyte with 85.3 % retained ability after 1000 cycle runs. This work paves a road for developing high‐performance HER electrocatalysts. His and HER: Nitrogen doped Cu2S/MoS2 heterojunction nanorod arrays grafted on copper foam in situ have been created for efficient hydrogen evolution reaction. The results showed the remarkably improved catalytic activity by designing and tuning the heterostructure, conductivity and active sites. [ABSTRACT FROM AUTHOR]

• Composite of CePO 4 with Ni as a HER catalyst is reported. • CePO 4 lead to enhanced electrical conductivity and H 2 desorption ability. • Ni/CePO 4 shows excellent electrocatalytic HER performance at high current density. • Mechanism of photocatalytic HER over CePO 4 -Ni with Eosin Y photosensitizer and electrocatalytic HER are proposed. Developing suitable electrocatalyst/photocatalyst cocatalyst with electron transfer and desorption of hydrogen active sites is extremely significance for hydrogen evolution reaction (HER). Herein, we develop a series of Ni/(m)CePO 4 catalyst with rich interfaces via thermal treatment at low temperature with Ni-BTC/CePO 4 as precursor. The as-synthesized Ni/(m)CePO 4 heterojunction possess compact heterogeneous interface, and large specific surface area by loading Ni nanosphere on CePO 4 nanowire. By carefully designing method, the powerfully intimated heterointerface between Ni and CePO 4 conducive to the conversion of adsorption energy toward H atoms and electron conductivity, which enhance the synergic effect for electro-/photo-catalytic HER performances. Impressively, the Ni/0.1CePO 4 catalyst renders outstanding electrocatalytic HER activity with an lowest overpotential of −120 mV at −10 mA cm−2 and a optimal Tafel slope of 72 mV dec−1. The overpotential of Ni/0.1CePO 4 catalyst is −288 mV at −100 mA cm−2, close to 20 wt% Pt/C. With Eosin Y as photosensitizer, the photocatalytic performance for H 2 generation speed is around 64 umol h−1. Additionally, the Ni/0.1CePO 4 catalyst exhibits wonderful cycle stability in both electro-/photo-catalytic HER. The possible speculation of mechanisms of HER have also been proposed. This work provides a new insight into design HER catalysts for electro-/photo-catalytic hydrogen evolution reaction. [ABSTRACT FROM AUTHOR]

Three dimensional (3D) magnetic graphene oxide–chitosan (GO–CS) composites with orderly self-assembled magnetite (Fe 3 O 4 ) nanoparticles (GO–CS–Fe3O4) were successfully fabricated. First, the covalent functionalization of graphene oxide (GO) using chitosan (CS) was successfully accomplished via a facile amidation process, forming a 3D network. In the as-fabricated GO–CS composites, GO sheets remained less aggregated, exhibiting a large surface area, and the interconnected pores in the hydrogels allowed object molecules to diffuse easily into the composites. Subsequently, the GO–CS–Fe 3 O 4 composites were synthesized using FeCl 3 ·6H 2 O and GO–CS composite as the starting materials through a solvothermal reaction. The resulting composite combined the features of the high surface area of GO, abundant amino, and hydroxyl functional groups of CS, and the magnetic response of magnetic nanoparticles. For further application, these composites were utilized to immobilize Candida rugosa lipase via different routes, and they showed excellent immobilization capacities. [ABSTRACT FROM AUTHOR]

A facile one-pot synthesis of size-tunable mesoporous carboxyl-functionalized magnetic colloidal nanocrystal clusters (MCNCs) with high magnetization (82.0 emu/g), large surface area (95 m 2 /g), and excellent colloidal stability has been developed. The mesostructured MCNCs were synthesized by a solvothermal approach with iron (III) chloride hexahydrate as a precursor, ethylene glycol as a reducing agent, ammonium acetate as a porogen, and ethylenediaminetetraacetic acid disodium salt (EDTA-2Na) as a surface-modification agent. Glucoamylase was immobilized onto the mesoporous MCNCs via the different routes. These immobilized glucoamylase exhibited excellent thermal stability and reusability in comparison with the free enzyme. The residual activity of immobilized enzyme remained above 65% after 6 h, while free glucoamylase was only left over 45% of the initial activity. And the residual activity of the immobilized enzyme was about 60% of the initial activity after the 10th reuse. [ABSTRACT FROM AUTHOR]

Highlights: [•] The monodisperse magnetic polystyrene microbeads were chosen as the base of support. [•] The magnetic microbeads is of dispersion and abundant functional groups. [•] Functionalizable and metal-chelate surfaces for reversible enzyme immobilization. [•] The regenerated biocatalyst still reserved its original performance. [ABSTRACT FROM AUTHOR]

We report a facile fabrication of a host-metal-guest coordination-bonding system in a mesostructured Fe3O4/chitosan nanoparticle that can act as a pH-responsive drug-delivery system. The mesostructured Fe3O4/chitosan was synthesized by a solvothermal approach with iron(III) chloride hexahydrate as a precursor, ethylene glycol as a reducing agent, ammonium acetate as a porogen, and chitosan as a surface-modification agent. Subsequently, doxorubicin (DOX), acting as a model drug (guest), was loaded onto the mesostructured Fe3O4/chitosan nanoparticles, with chitosan acting as a host molecule to form the NH2ZnIIDOX coordination architecture. The release of DOX can be achieved through the cleavage of coordination bonds that are sensitive to variations in external pH under weakly acidic conditions. The pH-responsive nature of the nanoparticles was confirmed by in vitro releases and cell assay tests. Furthermore, the relaxation efficiency of the nanoparticles as high-performance magnetic resonance imaging contrast agents was also investigated. Experimental results confirm that the synthesized mesostructured Fe3O4/chitosan is a smart nanovehicle for drug delivery owing to both its pH-responsive nature and relaxation efficiency. [ABSTRACT FROM AUTHOR]

A simple preparation process for the monodispersed pH-sensitive core-shell magnetic microspheres was carried out consisting of chitosan self-assembled on magnetic iron oxide nanoparticles. Meanwhile, glucoamylase was immobilized as a model enzyme on this carrier of FeO/CS microspheres by ionic adsorption. The morphology, inner structure, and high magnetic sensitivity of the resulting magnetic chitosan microspheres were studied, respectively, with a field emission scanning electron microscope (SEM), transmission electron microscope (TEM), FT-IR spectroscopy, thermogravimetric analysis (TGA), and a vibrating sample magnetometer (VSM). Subsequently, the properties of glucoamylase immobilized on the regenerated supports were also investigated by determining storage stability, pH stability, reusability, magnetic response, and regeneration of supports. The results from characterization and determination remarkably indicated that the immobilized glucoamylase obtained presents excellent storage stability, pH stability, reusability, magnetic response, and regeneration of supports. Therefore, this kind of magnetic FeO/CS microspheres with perfect monodispersity should be an ideal support for enzyme immobilization. [ABSTRACT FROM AUTHOR]

Abstract: Magnetic SBA-15 (FeSBA-15) was prepared via wet impregnation, calcination and reduction, and p(glycidylmethacrylate) (PGMA) was grafted on the surface of FeSBA-15 using surface-initiated atom transfer radical polymerization (SI-ATRP) for a prescribed time. The epoxy groups of the PGMA were reacted with Cu(II) metal–ligand complex (i.e., imidazole or iminodiacetic acid) to form metal–chelate brush. Subsequently, the functionalized FeSBA-15 as a regenerated support was used for enzyme immobilization. Glucoamylase was immobilized as a model enzyme on the regenerated supports through metal-ion affinity interactions. The quality of glucoamylase immobilized on the regenerated supports is defined by determining of the enzyme activity, thermal stability, and reusability. The results indicate that the metal–chelate brushes offer an efficient route to immobilize enzymes via metal-ion affinity interactions. The applicability of the regenerated supports in the current study is relevant for the conjugation of other enzymes beyond glucoamylase. [Copyright &y& Elsevier]

Investigates the association between abnormal phosphorylation sites found in Alzheimer disease and the inhibition of its biological activity. Techniques used to prepare and phosphorylate human recombinant; Effect of different kinases on microtubule binding activity; Inhibition of microtubule binding activity.

Developing high-performance nonprecious-metal electrocatalysts for the oxygen evolution reaction (OER) is crucial for efficient water splitting. Therefore, the reasonable design principle of catalyst, leading to high activity catalytic center and improving the accessibility of active sites, is undoubtedly crucial. Here, we used a kind of Prussian blue analogue (CoFe-PBA) nanoparticles to anchor the nitrogen-carbon doped CoFe 2 O 4 (CoFe 2 O 4 @NC) species to reduced graphene oxide aerogels as OER catalysts. The strong interaction between nanosized CoFe 2 O 4 @NC and the graphitic carbon shell led to synergistic effects in the OER, and the protection of the carbon shell guaranteed stability of the catalyst. As a result, the aerogel electrocatalyst exhibits more excellent activity and stability than the most advanced RuO 2 catalyst in OER under the same mass load in alkaline medium. It shows smaller overpotential of 250 mV to afford a current density of 10 mA cm−2 in a continuous working time of more than 70 hours. [Display omitted] • The catalyst has highly exposed active surface, multi-dimensional mass transfer pathway and good charge transfer ability. • The in-situ formation of nitrogen-carbon doped structure can greatly improve the catalytic activity and stability. • The binary active sites on the conductive GA network reduce the interfacial resistance and enhance catalytic activity. • The "Plum Pudding Model" structure integrates multiple requirements for catalyst design strategies. [ABSTRACT FROM AUTHOR]

Low-cost and earth-rich electrocatalysts with excellent catalytic activity in the electrochemical hydrogen evolution reaction (HER) are essential for large-scale renewable energy storage. Herein, we report a new type of core-shell Ni 2 P@CoP nanoarrays supported on nickel foam (NF) (Ni 2 P@CoP/NF) with large specific surface area, serving as an efficient cathode for hydrogen evolution reaction (HER). Plenty of tiny Ni 2 P nanosheets were tightly wrapped on the CoP nanowires, forming a rich heterostructure interface, which can provide more active sites and improve conductivity, thereby increasing their catalytic performance. What's more, the synergistic effect between Ni 2 P and CoP can promote the rapid electron transfer and improve the catalytic efficiency. The obtained Ni 2 P@CoP/NF NAs exhibited excellent HER activity with a low overpotential of 61 mV at 10 mA cm−2 and good durability in the alkaline media. The core-shell nanoarray structure of Ni 2 P@CoP/NF provides a novel method for the preparation of other heterojunction metal phosphides, which can be used to develop high performance HER electrocatalysts. [Display omitted] • Designed a new type of core-shell Ni 2 P@CoP nanoarrays supported on nickel foam. • The catalyst has a large specific surface area and rich heterostructure interfaces, which can provide more active sites. • The synergistic effect between Ni 2 P and CoP can promote the rapid electron transfer. • The obtained catalyst exhibits remarkable enhanced HER activities compared to pure Ni 2 P and CoP nanostructures. [ABSTRACT FROM AUTHOR]

Background: Increased level of serum cholic acid (CA) is often accompanied with decreased CYP2E1 expression in hepatocellular carcinoma (HCC) patients. However, the roles of CA and CYP2E1 in hepatocarcinogenesis have not been elucidated. This study aimed to investigate the roles and the underlying mechanisms of CYP2E1 and CA in HCC cell growth. Methods: The proteomic analysis of liver tumors from DEN-induced male SD rats with CA administration was used to reveal the changes of protein expression in the CA treated group. The growth of CA-treated HCC cells was examined by colony formation assays. Autophagic flux was assessed with immunofluorescence and confocal microscopy. Western blot analysis was used to examine the expression of CYP2E1, mTOR, AKT, p62, and LC3II/I. A xenograft tumor model in nude mice was used to examine the role of CYP2E1 in CA-induced hepatocellular carcinogenesis. The samples from HCC patients were used to evaluate the clinical value of CYP2E1 expression. Results: CA treatment significantly increased the growth of HCC cells and promoted xenograft tumors accompanied by a decrease of CYP2E1 expression. Further studies revealed that both in vitro and in vivo, upregulated CYP2E1 expression inhibited the growth of HCC cells, blocked autophagic flux, decreased AKT phosphorylation, and increased mTOR phosphorylation. CYP2E1 was involved in CA-activated autophagy through the AKT/mTOR signaling. Finally, decreased CYP2E1 expression was observed in the tumor tissues of HCC patients and its expression level in tumors was negatively correlated with the serum level of total bile acids (TBA) and gamma-glutamyltransferase (GGT). Conclusions: CYP2E1 downregulation contributes to CA-induced HCC development presumably through autophagy regulation. Thus, CYP2E1 may serve as a potential target for HCC drug development. [ABSTRACT FROM AUTHOR]

[Display omitted] Covalent organic frameworks (COFs) with controlled porosity, high crystallinity, diverse designability and excellent stability are very attractive in metal-free heterogeneous photocatalysis of volatile organic compounds (VOCs) degradation. In order to construct the high optimal performance COFs under feasible and universal conditions, herein, the visible light-driven hollow COF TAPB-PDA (H-COF TAPB-PDA) microcapsule was designed by a facile dual-ligand regulated sacrificial template method. The H-COF TAPB-PDA microcapsule possesses improved surface area, high crystallinity, broad absorption range and high stability, which enables enhanced substrates and visible light adsorption, photogenerated electrons-holes separation and transfer, and facilitate the generation of reactive radicals. Importantly, it was found to be a highly efficient photocatalyst for toluene degradation under visible-light irradiation compared with the solid COF TAPB-PDA , and the degradation efficiency of toluene reached 91.8 % within 180 min with the conversion rate of CO 2 was 68.9 %. Additionally, the H-COF TAPB-PDA presented good recyclability and long-term stability after multiple photocatalytic reuses. Furthermore, the active sites of H-COF TAPB-PDA in photocatalytic degradation of toluene was proposed by XPS and DFT calculations, and the degradation pathway and mechanism was proposed and analyzed. The result presented great prospect of morphologic design of hollow COFs in metal-free heterogeneous photocatalysis for VOCs degradation. [ABSTRACT FROM AUTHOR]

Designing ultrahigh energy density and mass-loading of electrocatalysts for hydrogen evolution is highly desirable but remains a great challenge. Herein, a 3D high-rise architectural structure consisting of dense Ni(OH) 2 nanoparticles on CuMoO 4 nanocube heterostructure arrays on Ni foam (Ni(OH) 2 /CuMoO 4 /NF) is developed via a hydrothermal reaction, calcination and electrodeposition method. Benefitting from the optimized electronic configuration, hierarchical high-rise architecture, and large specific surface area and mesoporous, the Ni(OH) 2 /CuMoO 4 /NF exhibits superior hydrogen evolution reaction (HER) activity in 1.0 M KOH solution. Ni(OH) 2 /CuMoO 4 /NF only requires low overpotential of 70 mV achieving a current density of 10 mA cm−2 with a low Tafel slope of 80 mV dec−1, and superior long-term stability toward HER. This work provides a new structural design to high-rise architectural structures for efficient catalytic application. [Display omitted] • A highly topological nickel hydroxide doped copper molybdate oxide composite was synthesized. • The high-topology structure with a heterogeneous interface enhances the conductivity. • The typical structure and proper components contribute to the electrochemical activity. [ABSTRACT FROM AUTHOR]

Background: Alzheimer's disease (AD) and related Tauopathies are characterised by the pathologically hyperphosphorylated and aggregated microtubule‐associated protein Tau, which is accompanied by neuroinflammation mediated by activated microglia. However, the role of Tau pathology in microglia activation or their causal relationship remains largely elusive. Methods: The levels of nucleotide‐binding oligomerisation domain (NOD)‐like receptor pyrin domain containing 3 (NLRP3) acetylation and inflammasome activation in multiple cell models with Tau proteins treatment, transgenic mice with Tauopathy, and AD patients were measured by Western blotting and enzyme‐linked immunosorbent assay. In addition, the acetyltransferase activity of Tau and NLRP3 acetylation sites were confirmed using the test‐tube acetylation assay, co‐immunoprecipitation, immunofluorescence (IF) staining, mass spectrometry and molecular docking. The Tau‐overexpressing mouse model was established by overexpression of human Tau proteins in mouse hippocampal CA1 neurons through the adeno‐associated virus injection. The cognitive functions of Tau‐overexpressing mice were assessed in various behavioural tests, and microglia activation was analysed by Iba‐1 IF staining and [18F]‐DPA‐714 positron emission tomography/computed tomography imaging. A peptide that blocks the interaction between Tau and NLRP3 was synthesised to determine the in vitro and in vivo effects of Tau–NLRP3 interaction blockade on NLRP3 acetylation, inflammasome activation, microglia activation and cognitive function. Results: Excessively elevated NLRP3 acetylation and inflammasome activation were observed in 3xTg‐AD mice, microtubule‐associated protein Tau P301S (PS19) mice and AD patients. It was further confirmed that mimics of 'early' phosphorylated‐Tau proteins which increase at the initial stage of diseases with Tauopathy, including TauT181E, TauS199E, TauT217E and TauS262E, significantly promoted Tau–K18 domain acetyltransferase activity‐dependent NLRP3 acetylation and inflammasome activation in HEK293T and BV‐2 microglial cells. In addition, Tau protein could directly acetylate NLRP3 at the K21, K22 and K24 sites at its PYD domain and thereby induce inflammasome activation in vitro. Overexpression of human Tau proteins in mouse hippocampal CA1 neurons resulted in impaired cognitive function, Tau transmission to microglia and microgliosis with NLRP3 acetylation and inflammasome activation. As a targeted intervention, competitive binding of a designed Tau–NLRP3‐binding blocking (TNB) peptide to block the interaction of Tau protein with NLRP3 inhibited the NLRP3 acetylation and downstream inflammasome activation in microglia, thereby alleviating microglia activation and cognitive impairment in mice. Conclusions: In conclusion, our findings provide evidence for a novel role of Tau in the regulation of microglia activation through acetylating NLRP3, which has potential implications for early intervention and personalised treatment of AD and related Tauopathies. [ABSTRACT FROM AUTHOR]

Two rhodamine B-based Schiff bases (RBF, RBC) with different substituent groups (-F and -COOH) have been synthesized. In order to study the sensing properties of two Schiff bases for metal ions, the interaction of Schiff bases with different metal ions was studied over UV-Vis absorption spectra and photofluorescent spectra. The results show that the RBF is a turn-on fluorescent chemosensor for Al3+ ions with being highly selective and sensitive in ethanol. The value of the fluorescence increase factor shows a good linear relationship with the concentration of Al3+ in the range of 1-9 μM with a detection limit of 0.8 μM. Meanwhile, upon addition of Al3+ or Fe3+ ions, the fluorescence intensity of RBC increased significantly (FFe3+FAl3+=0.77). These studies show that, compared with the carboxyl group (-COOH), the introduction of fluorine atoms (-F) to a rhodamine B-based Schiff base can significantly improve selectivity to Al3+. [ABSTRACT FROM AUTHOR]

Developing earth-abundant, low-cost, high-efficiency electrocatalysts for hydrogen evolution reaction (HER) by structure design is still a grand challenge. Herein, we fabricated Ni nanoparticles encapsulated by carbon loaded in two-dimensional carbon nanosheets (2D Ni@C@SU) using a molten salt (NaCl)-assisted pyrolysis method. Because of the large specific surface area (262.35 m²/g) and high electrical conductivity, the prepared 2D Ni@C@SU-0.75 electrocatalyst exhibits excellent HER electrocatalytic activity with the overpotential of −105 mV at −10 mA cm−2 and −367 mV at −200 mA cm−2, which is close to the commercial benchmark Pt/C (η 200 = −339 mV). Besides, the catalyst displays incredible durability in the electrocatalytic HER. This research indicates that the green solid-state synthetic strategy provides a new window for designing new Ni-based composite catalysts for electrocatalytic HER. [Display omitted] • Catalysts were prepared by a facile one-step synthesis. • The synthesis process is green and solvent-free. • Ni@C@SU-0.75 catalyzes hydrogen evolution reaction with -105 mV at 10 mA/cm2, and exhibited a good stability. • The 2D nanosheets encapsulated structure can increase the active sites and promote proton/electron transport. [ABSTRACT FROM AUTHOR]

FeNi bimetallic oxides are considered as a potential catalyst candidate material for efficient oxygen evolution. However, low conductivity, rapid structural collapse, and metal ion release always lead to electrochemical performance and poor stability, which become major challenges in the electrochemical process. Herein, we synthesized self-standing 3D rose-like bimetallic oxides modified nitrogen-doped graphite aerogels (FeNiOx@N/GA) by the facile layer-by-layer self-assembled method. The unique 2D/3D structure composed of 2D ultrathin graphene nanosheets decorated 3D microflowers can provide a large active area and a rapid charge transfer rate. Moreover, both oxidation and nitrogen doping can improve the reaction kinetics of the material, thereby exhibiting higher catalytic activity. FeNiO X @N/GA exhibits excellent oxygen evolution reaction (OER) performance (η 10 =291 mV) and low Tafel slope (39 mV dec−1) in the 1 M KOH. This work can be expected to provide a novel and valid method for rational design and manufacture of advanced bimetallic oxides-based positive electrode toward efficient OER. Meanwhile, FeNiOx@N/GA is loaded on nickel foam and displays good electrochemical properties as an air-cathode in Zn-Air battery, demonstrating outstanding practicability. [Display omitted] [ABSTRACT FROM AUTHOR]

The design and fabrication of stable, high-performance, and affordable oxygen evolution reaction (OER) electrocatalysts is essential for performing practical water electrolysis and generating green hydrogen energy. Here, we report that 2D few layer Ni 3 Fe nanosheets embedded with 2D porous nitrogen doped carbon (N-Ni x Fe@CF) from asphalt waste and then convolved and assembled into 1D hollow nanotube structures by Lewis acid molten salt etching method, which were used as electrocatalysts for OER. Benefiting from the integrate of 1D hollow nanotube structure and 2D porous nanosheets, the close contact between catalysts and support, and the increased conductivity, the resultant N-Ni 3 Fe@CF catalysts exhibited high catalytic activities in the OER with low overpotential at a current density of 10 mA cm−2 (114 mV), low Tafel slope (166.6 mV dec−1), and excellent electrochemical stability. This work provides a new concept for expanding the use of asphalt wastes and by-products, as well as a straightforward synthesis method for producing economical, efficient, and long-lasting alkaline OER electrocatalysts. • A 1D hollow nanotube shape N-Ni x Fe@CF was prepared by Lewis acid molten salt etching method. • The N-Ni x Fe@CF exhibits excellent electrocatalytic activity for oxygen evolution reaction. • It outperforms commercial noble metal-based catalyst of RuO 2 and most catalysts reported so far. • The outstanding OER activity is ascribed to the novel synthetic process and porous structure. [ABSTRACT FROM AUTHOR]

Object handover is one of the fundamental tasks of service robots. This paper focuses on a robot-to-human object handover controller applied to a domestic service robot. People in need often have manual operation constraints caused by different body postures or declined physical functions. The preplanned handover strategy used in previous studies potentially increases their cognitive burden and makes it difficult to meet their needs for flexible real-time control and intuitive interaction. It also remains challenging to deal with sensing and prediction errors, motion planning and coordination. The robot no longer provides assistance after an object is delivered to a preplanned handover location, and the receiver needs to make extra efforts to get the object released. Therefore, inspired by a human study, a handover controller is designed based on a manually guided handover strategy that solve problems from grasp adjustment to object release in dynamic retraction motion. Flexible control and intuitive interaction are enabled through motion with continuous support from the robot. Without additional sensors or modeling learning, changes in motion and energy consumption are taken into account to explore an appropriate release timing. The results of robot-to-human handover experiments and the user studies indicate that the receiver can freely pull an object to a suitable location as desired and smoothly obtain the object’s control to complete a subsequent task using the proposed controller with proper release timing. [ABSTRACT FROM AUTHOR]

• The content of total nitrogen and ammonia nitrogen in pit mud was rapidly detected. • The characteristic wavelength is extracted by the combination of VCPA-IVSO. • Four prediction models (ELM, SVM, LSSVM, PSO-LSSVM) are established. Total nitrogen and ammonium nitrogen play a pivotal role in preserving the soil's nutrient ecosystem, and rapid determination of their levels in the soil can help improve soil utilization. In this study, hyperspectral imaging technology(HSI) was used to achieve rapid determination of total and ammonia nitrogen in pit mud. Both types of spectral data were pre-processed and the characteristic wavelengths were screened using a combination of variable combined population analysisand iterative variable subset optimization (VCPA-IVSO). Four prediction models (ELM, SVM, LSSVM, PSO-LSSVM) based on characteristic wavelengths and full wavelengths were developed. The results showed that the PSO-LSSVM model with the NIR characteristic wavelengths was more effective in predicting total and ammonia nitrogen in pit sludge (total nitrogen: R c 2 = 0.9999, RMSEC = 0.0014, R p 2 = 0.9892, RMSEP = 0.0111, RPD = 9.6225; ammonia nitrogen: R c 2 = 0.9941, RMSEC = 4.3004, R p 2 = 0.9644, RMSEP = 9.8962, RPD = 5.3).The distribution of total nitrogen and ammonia nitrogen in the region of interest is visually analyzed using the determined best model. These results underscore the potential of HSI as a rapid and non-destructive method for detecting total and ammonia nitrogen levels in pit mud. [ABSTRACT FROM AUTHOR]

Background: Obesity is a worldwide health problem that has been implicated in many diseases, including Alzheimer's disease (AD). AD is one of the most common neurodegenerative disorders and is characterized by two pathologies, including extracellular senior plaques composed of amyloid-β (Aβ) and intracellular neurofibrillary tangles (NFTs) consisting of abnormally hyperphosphorylated tau. According to current research, a high-fat diet (HFD) could exacerbate Aβ accumulation, oxidative damage, and cognitive defects in AD mice. However, the accurate role of HFD in the pathogenesis of AD is far more unclear.Objective: To explore the accurate role of HFD in the pathogenesis of AD.Methods: Open Field, Barns Maze, Elevated zero-maze, Contextual fear condition, Tail suspension test, western blotting, immunofluorescence, Fluoro-Jade C Labeling, Perls' Prussian blue staining, and ELISA were used.Results: HFD caused nonheme iron overload in the brains of APPswe/PS1dE9 (APP/PS1) mice. Furthermore, the administration of M30 (0.5 mg/kg) for iron chelation once every 2 days per os (p.o.) for 1 month remitted memory deficits caused by HFD in APP/PS1 mice. Notably, a variety of hematological parameters in whole blood had no difference after iron chelation. In addition, iron chelation effectively reduced synaptic impairment in hippocampus and neuronal degeneration in cortex in the HFD-fed APP/PS1 mice. Meanwhile, iron chelation decreased Aβ1-40 and Aβ1-42 level as well as neuroinflammation in HFD-fed APP/PS1 mice.Conclusion: These data enhance our understanding of how HFD aggravates AD pathology and cognitive impairments and might shed light on future preclinical studies. [ABSTRACT FROM AUTHOR]

4,4′-Spirobi[pentacyclo[5.4.0.0 2,6 .0 3,10 .0 5,9 ]undecane] ( 10 ) is first successfully prepared by a nine step synthetic scheme starting from the key intermediate (cyclopentadiene derivate, 2 ). This synthetic scheme avoids using the hardly obtainable spiro[4.4]nonatetraene ( 18 ) as the starting material. In the structure of 10 , two polycyclic cages share one spiro-carbon so that it has high density (1.2663 g/cm 3 ) and high volumetric heat of combustion (53.353 MJ/L). [ABSTRACT FROM AUTHOR]

The key to the layout of the roof horizontal long drilling hole is to accurately locate the range of gas-conducting fracture zone. In this paper, the discrete element method (DEM) is firstly adopted to quantitatively simulate the porosity distribution in goaf from a microscopic perspective, with the 6306 working face of the Tangkou coal mine as an engineering example. Then, the three-dimensional porosity distribution data is extracted and converted into a two-dimensional array form, which was verified by the mathematical model established by previous work. After that, combining the DEM data and mathematical model result, user-defined function (UDF) codes are written and imported into computational fluid dynamics (CFD) software to simulate the gas distribution in the goaf before and after the drilling of the working face. The results show that the gas in goaf is mainly distributed in the upper position after drilling, and the proportion of gas in the bottom position is largely reduced. The boreholes arrangement in the gas-guiding fissure zone is reasonable effectively reducing the gas concentration in goaf. [Display omitted] • Analysis of the gas-guiding fissure zone from a macro and mesoscopic perspective. • The model porosity data set is obtained based on the DEM simulator. • The porosity data into a two-dimensional array and import it into CFD. [ABSTRACT FROM AUTHOR]

[Display omitted] • N-doped biomass material with photocatalytic properties was synthesized. • Material functioned as an optical sensor for detecting and degrading PFOA. • PFOA's specific recognition was achieved using the 4-tert-butylcalix[6]aromatic. • Proposed mechanism for PFOA detection and degradation. In this study, we successfully synthesized SMIP@N-CF, a nitrogen-doped biomass carbon fiber, using supramolecular imprinting technology. This material has good perfluorooctanoic acid (PFOA) adsorption properties and excellent photocatalytic ability. Therefore, it is possible to apply SMIP@N-CF to the detection system of PFOA for visual detection and to the photocatalytic process based on peroxymonosulfate (PMS) for the degradation of PFOA. The Independent Gradient Model (IGM) explains that visual detection relies on the rapid adsorption of PFOA by functional monomers, covering the catalytic site and resulting in a color change. Experimental evidence verifies its good linear response within the 0.07–90 µM range. Density Functional Theory (DFT) elucidates that charge transfer between pyridine N and C atoms activated PMS to produce reactive oxygen species to degrade PFOA, and the final degradation rate reached 94.3 %. The successful application of SMIP@N-CF provides a new idea for further understanding nitrogen-doped biomass materials and provides a scientific basis for detecting and degrading PFOA in water. [ABSTRACT FROM AUTHOR]

Developing highly efficient, low-cost and superior stable electrocatalysts for the oxygen evolution reaction (OER) is essential for coping with global energy shortage and environmental crisis. In this article, a polymetallic catalyst of ultrathin Fe(OH) 3 nanosheets uniformly embedded in NiCo 2 O 4 porous nanotube arrays (Fe(OH) 3 -NiCo 2 O 4 /NF) was synthesized via a simple hydrothermal-annealing and electrodeposition method. Benefits from the synergistic effect and their unique interactions between Fe(OH) 3 and NiCo 2 O 4 , the Fe(OH) 3 -NiCo 2 O 4 /NF triggers optimum electronic properties, rich multiple active sites, and favorite free adsorption energy, resulting in excellent OER catalytic activities. Meanwhile, the highly porous of Fe(OH) 3 and NiCo 2 O 4 effectively promotes a multichannel architecture for charge transfer and gas/ion diffusion to improve stability. Such core-shell Fe(OH) 3 -NiCo 2 O 4 /NF hybrid was used as a polymetallic catalyst, exhibiting a small overpotential of 268 mV at a current density of 50 mA cm−2 and low Tafel slope of 73.1 mV dec−1 for OER in 1 M KOH. In the battery system with Fe(OH) 3 -NiCo 2 O 4 /NF as the cathode and zinc sheet as the anode, the zinc-air battery (ZAB) exhibits an open-circuit voltage of 1.32 V and an instantaneous current of 0.96 A. This material provides a new idea for the coupling of amorphous materials and transition metal compound, and the application of ZAB. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • 2D MOFs-based nanosheets with rich oxygen vacancies were designed. • The Kirkendall effect successfully regulated the oxygen vacancies. • The presence of oxygen vacancies improved the photocatalytic ability of the cathode. • PFOA degradation and TOC removal efficiency reached 93 % and 92 % in 180 min. • The mechanism of adsorption and degradation of PFOA in heterogeneous systems was described clearly. In heterogeneous solar photo-electro-Fenton (SPEF) degradation of perfluorooctanoic acid (PFOA), improving the binding energy between the catalyst and PFOA on a surface molecular level to facilitate absorption, diffusion, and degradation is a great challenge. Herein, we attained this goal in two steps: First, developing of two-dimensional (2D) MOFs-based CoFe nanosheets with layered structures as photo-electrocatalysts, which own abundant unsaturated coordination sites to accelerate rapid mass transport and charge transfer. Secondly, the construction of abundant oxygen vacancies (OVs) at low temperatures in 2D CoFe causes hybridization of the d-band of Fe and LUMO orbital of O in PFOA, enhancing PFOA's binding capacity by theoretical analysis. OVs also reduced the band gap of CoFe and increased the efficiency of electron-hole separation, thereby improving photo-electrocatalytic activity and enabling rapid degradation of PFOA. Moreover, it can maintain a good degradation effect in complex ionic background conditions and actual water samples. These findings extend the applications of catalysts and consolidate the effect of OVs on photo-electrocatalysis for wide environmental applications. [ABSTRACT FROM AUTHOR]

[Display omitted] • Cu-MOFs derived CNF/Cu-C dual-functional membrane catalyst was synthesized. • Simultaneously efficient visual detection and SPEF degradation of PFOA are proposed. • PFOA inhibited peroxidase-like activity of CNF/Cu-C by hindering Cu active sites. • Enhanced degradation and mineralization efficiency of PFOA via SPEF are achieved. • States of active Cu species is regulated for enhanced photo-electric property. Developing bi-functional materials to simultaneously detect and degrade persistent pollutant perfluorooctanoic acid (PFOA) is of significant importance for environmental and human health. In this study, a copper-based mimic enzyme colorimetric detecting sensor coupling with solar photo-electro-Fenton degradation (SPEF) system was built based on Cu/carbon nanofiber (CNF-Cu/C) membrane. Self-supporting flexible CNF-Cu/C membrane was successfully prepared by solvothermal method with further secondary seed growth and in-situ thermal reduction. Based on calcination temperature regulation, the obtained CNF-Cu/C membrane derived from MOFs/polyacrylonitrile (HKUST/PAN) membrane was characterized by 3D carbon fiber network dispersed with porous carbon skeleton embedded copper species, which exhibited good dispersibility, cycling stability and excellent electrical conductivity. With excellent peroxidase-like activity, CNF-Cu/C can rapidly detect PFOA based on the inhibition of color reaction of tetramethylbenzidine (TMB) with detection limit of 0.133 μM. Furthermore, CNF-Cu/C also exhibited outstanding optical properties and oxygen redox reaction (ORR) activity, and the removal efficiency of PFOA in Cu-SPEF system reached 98.22 % within 180 min under optimal conditions. Based on the results of free radical quenching experiment, EPR experiment and HPLC-MS experiments, the degradation mechanism and degradation path of PFOA by SPEF system were further speculated. [ABSTRACT FROM AUTHOR]

• The alternation of AD-like pathology is similar in two STZ mouse models. • The deficits of insulin signaling occur in both of STZ mouse models. • Rapamycin reverses AD-like pathology in two STZ mouse models. • Rapamycin improves AKT/AMPK/p70s6/GSK-3β signal pathway. Alzheimer's disease (AD) and type 2 diabetes mellitus (T2DM) share some pathological features, including tau hyperphosphorylation and deficits in insulin signaling, but the underlying mechanism and effective drugs for treating AD are unknown. The AD-like brain impairments are almost same in both of mouse type 2 DM models induced by the multiple low-dose intraperitoneal (i.p.) streptozotocin (STZ) injection and twice intracerebroventricular (i.c.v.) STZ injection. We found that memory disorders, impairment of insulin signaling, and AD-like tauopathies were exhibited in two different STZ-induced mouse models and that the level of Advanced Glycation End Products (AGEs) was increased in two STZ mouse models. Inhibition of mTORC1 with rapamycin reversed the deficits of insulin signaling associated kinases activity, decreased levels of AGEs and AD-like tau phosphorylation, and also improved memory deficit in both STZ mice. Rapamycin attenuated HG-induced tau hyperphosphorylation via the AKT/AMPK/GSK-3β pathways and p70S6K in SH-SY5Y cells. Taken together, these data demonstrated that rapamycin improved STZ-induced AD-like tauopathies and memory deficit in mice via improving p70S6K and AKT/AMPK/GSK-3β signaling and decreasing AGEs. Therefore, regulating insulin signaling via mTORC1 is a new strategy for preventing T2DM-associated AD, and mTORC1 is a potential drug target. [ABSTRACT FROM AUTHOR]

Background: Abnormally hyperphosphorylated tau is the major protein of neurofibrillary tangles in Alzheimer's disease. Insulin activates PI3K-AKT signaling and regulates tau phosphorylation. Impaired brain insulin signaling is involved in Alzheimer's disease pathogenesis. However, the effect of peripheral insulin on tau phosphorylation is controversial.Objective: In the present study, we determined the effect of peripheral insulin administration on tau phosphorylation in brain.Methods: We intraperitoneally injected a super physiological dose of insulin to mice and analyzed PI3K-AKT signaling and tau phosphorylation in brains by western blots.Results: We found that peripherally administered insulin activated the PI3K-AKT signaling pathway immediately in the liver, but not in the brain. Tau phosphorylation in the mouse brain was found to be first decreased (15 min) and then increased (30 min and 60 min) after peripheral insulin administration and these changes correlated inversely with body temperature and the level of brain protein O-GlcNAcylation. Maintaining body temperature of mice post peripheral insulin administration prevented the insulin/hypoglycemia-induced tau hyperphosphorylation after peripheral insulin administration.Conclusion: These findings suggest that peripheral insulin can induce tau hyperphosphorylation through both hypothermia and downregulation of brain protein O-GlcNAcylation during hypoglycemia. [ABSTRACT FROM AUTHOR]

A nitrogen doped bio-carbon catalyst with high specific surface area and a hierarchical interconnected porous structure was fabricated by an in situ gas-foaming strategy from sodium alginate and ammonium chloride. The optimized catalyst displays a fabulous ORR activity, providing a facile approach for the mass production of metal-free bio-carbon catalysts in fuel cells and metal–air batteries. [ABSTRACT FROM AUTHOR]

Abstract The electrochemical properties of carbon nanofibers for supercapacitor application should be improved to meet the requirement of renewable energy systems. Herein we investigate the effect of MnCo 2 O 4 on the electrochemical properties of carbon nanofibers. Nitrogen-doped carbon nanofibers incorporated with MnCo 2 O 4 nanoparticles are synthesized by carbonizing manganese-cobalt@polyacrylonitrile nanofibers under N 2 atmosphere. The composite electrode-based symmetric supercapacitor at an optimum loading of 1/2 mmol has an excellent specific capacitance of 871.5 F g−1 (at a current density of 0.5 A g−1), presents an ultra-high energy density of 30.26 Wh kg−1 and delivers an excellent cycle performance (retention rate of 89.3% after 5000 cycles). The outstanding electrochemical properties of composite electrode are mainly attributed to the doping of nitrogen and the introduction of MnCo 2 O 4 into carbon matrix. The adoption of PAN is aimed to produce the doped nitrogen in carbon bulk, which can generate pseudocapacitance and improve the electrical conductivity of carbon nanofibers. The introduction of MnCo 2 O 4 results in the formation of meso-microporous structure in CNFs, which facilitates the rapid and efficient transfer of charges into the electrode material. Besides, MnCo 2 O 4 is an active material for pseudocapacitors that can undergo redox reaction during charge/discharge process, thus enhancing the electrochemical performance of carbon nanofibers. Graphical abstract Image 1 Highlights • MnCo 2 O 4 @N-CNF is fabricated by carbonization in N 2 atmosphere. • The addition of MnCo 2 O 4 to CNF induces meso-microporous structure. • MnCo 2 O 4 @N-CNF shows high specific capacitance of 871.5 F g−1. • Symmetric supercapacitor can deliver a high energy density of 30.26 Wh kg−1. • Good cyclability with more than 89.3% capacitive retention after 5000 cycles. [ABSTRACT FROM AUTHOR]

Alzheimer's disease (AD) is characterized by progressive impairment of learning, memory, and cognitive deficits. Glutamate is the major excitatory neurotransmitter in the central nervous system and plays an important role in learning, memory, and cognition. The homeostasis and reutilization of glutamate are dependent on astrocytic uptake by glutamate transporter-1 (GLT-1) and the subsequent glutamate-glutamine cycle. Increasing evidence showed impairments in GLT-1 expression and uptake activity and glutamate-glutamine cycle in AD. Ceftriaxone (Cef) has been reported to upregulate the expression and uptake of GLT-1. Therefore, the present study was undertaken to explore whether Cef can improve cognitive deficits of APP/PS1 mice in early stage of AD by upregulating GLT-1 expression, and then promoting the glutamate-glutamine cycle. It was shown that Cef treatment significantly alleviated the cognitive deficits measured by Morris water maze test and upregulated GLT-1 protein expression in the hippocampus of APP/PS1 mice. Particularly, the activity of glutamine synthetase (GS) and the protein expression of system N glutamine transporter 1 (SN1), which are the key factors involved in the glutamate-glutamine cycle, were significantly upregulated as well after the Cef treatment. Furthermore, inhibition of GLT-1 uptake activity by dihydrokainic acid, an inhibitor of GLT-1, blocked the Cef-induced improvement on the cognitive deficits, GS activity, and SN1 expression. The above results suggested that Cef could improve cognitive deficits of APP/PS1 mice in early stage of AD by upregulating the GLT-1 expression, GS activity, and SN1 expression, which would lead to stimulating the glutamate-glutamine cycle. [ABSTRACT FROM AUTHOR]

• The MIP Co/Fe@CNF can effectively detect and degrade wastewater containing PFOA. • Imprinted cavities can shorten the transfer distance between free radicals and target contaminants. • Compared to HPLC, MIP Co/Fe@CNF is effective in the detection process. • The catalytic mechanism of MIP Co/Fe@CNF in the detection and degradation process was revealed. The polyfuoroalkyl substances, especially perfluorooctanoic acid (PFOA), are emerging as harmful environmental micropollutants that are known to globally contaminate water, air, and soil resources. Herein considering the urgent demand for the sensitive detection and effective degradation of PFOA present in water environment, a novel molecular imprinting polymer (MIP) MOFs (Co/Fe)-driven carbon nanofiber (Co/Fe@CNF) electrode has been developed for electrochemical detection and electro-Fenton (EF) degradation of PFOA. MIP was formed by one-pot step by electro-polymerization of the pyrrole in the presence of PFOA template on the Co/Fe@CNF. The MIP has a strong adsorption force on PFOA for the special O–H-π hydrogen bond between PFOA and the imprinting site, helped PFOA to access the surface of electrode. Therefore, the resulting MIP Co/Fe@CNF was able to detect PFOA with a good linear response in the range of 1 × 10-8–9 × 10-5 M, and the limit of detection (LOD) was reached 1.073 × 10-9 M. Moreover, the imprinted cavity on MIP can precisely adsorb PFOA and its intermediates to shorten the transmission distance between free radicals and targets, which enhanced the degradation ability in the EF process, and the targeted degradation efficiency reached 93% with 180 min. [ABSTRACT FROM AUTHOR]

Due to the advantages of large specific surface area, high mass transfer efficiency and easy access to active sites, two dimensional (2D) nanomaterials provide a great opportunity for the construction of new versatile electrocatalysts with superior properties. Herein, a graphene-templated growth of MoS 2 -Ni 3 S 2 heterostructure with porous structure is successfully prepared on the Ni foam (MoS 2 /Ni 3 S 2 @G/NF) by one pot hydrothermal method. The electronic structure and surface properties of 2D chalcogenides are modified by heterogeneous interface and component engineering, so as to prepare a high-performance transition metal composite catalytic electrode for electrochemical reaction. The optimized MoS 2 /Ni 3 S 2 @G/NF shows excellent bifunctional activity and durability in alkaline medium. It only needs 53 mV and 265 mV overpotential to reach 10 mA cm−2 current density of HER and 20 mA cm−2 current density for OER, respectively. When the composite is used as an advanced electrocatalyst for water splitting, the 1.47 V voltage required to achieve a current density of 10 mA cm−2, which is better than the most non-noble metal electrocatalysts. The heterostructures between MoS 2 , Ni 3 S 2 and graphene are conducive to the synchronous chemical adsorption of hydrogen and oxygen-containing intermediates, which can improve the catalytic activity of overall water splitting. [Display omitted] • The synergy between MoS 2 nanosheets and Ni 3 S 2 particles enhances the intrinsic electrochemical activity of the material. • Graphene increases the load of active substances and regulates the interaction between electrons with faster carrier. • 3D nickel foam provides a binder free framework for catalytic reaction, greatly reducing charge transfer resistance. [ABSTRACT FROM AUTHOR]

The novel photocatalytic advanced oxidation catalyst, ZIF-67@MXene-TA-CNF (ZIF-67@MTC) aerogels, was prepared via introducing tannic acid-coated cellulose nanofibril (TA-CNF), two-dimensional layered MXene, and ZIF-67 into a composite aerogel network. Specially, TA assisted the crosslinking of CNF through hydrogen bonds to construct the flexible aerogel skeleton, accompanied by assembly of MXene and ZIF-67. MXene not only provided sufficient attachment sites for the anchoring of ZIF-67, but also can be used as a repository for electron transfer to facilitate the separation of photogenerated electrons and holes. In the peroxymonosulfate (PMS)/aerogels/visible light system, the SO 4 -, OH and 1O 2 were generated, and 1O 2 was the main reactive species. As a result, 99.9 % of Tetrabromobisphenol A (TBBPA) can be degraded and the total organic carbon (TOC) removal efficiency reached 81.8 % within 40 min in this system. The results might provide a new concept for the design of biomass aerogels for applications in organic pollutant removal. The ZIF-67/MXene/CNF aerogels could efficiently photocatalytic TBBPA degradation via peroxymonosulfate activation. [Display omitted] [ABSTRACT FROM AUTHOR]

A new 4,5-diazafluorene-based fluorescent chemosensor has been synthesized by Schiff base condensation of 9,9-bis(3,5-dimethyl-4-aminophenyl)-4,5-diazafluorene with salicylaldehyde. The interaction of Schiff base with different metal ions has been studied over photofluorescent spectra. The results showed that Schiff base exhibited 194-fold enhancements in fluorescence at 465 nm after Zn ions. Such fluorescent responses could be detected by naked eye under UV-lamp. The complex solution ( L-Zn) exhibited reversibility with EDTA. [ABSTRACT FROM AUTHOR]

Novel biomass energy self-driven solar photo-electro-Fenton system for efficient mineralization of PFOA. [Display omitted] • The novel biomass energy driven solar photo-electro-Fenton system was constructed. • CoFe-OVs@CNF electrode exhibited both photocatalytic and electrocatalytic ability. • PFOA was highly mineralized within 300 min with low energy consumption. • The toxicity evolution during PFOA degradation was evaluated. The smart eco-friendly biomass energy driven electrical degradation system was established by coupling of glucose fuel cells (GFC) and solar photo-electro-Fenton (SPEF) processes, which was proposed for the green, economical and efficient degradation of perfluorooctanic acid (PFOA). The CoFe alloy nanoparticles with oxygen defects (O*) based on metal–organic frameworks (MOFs) were decorated on polyacrylonitrile (PAN)-driven carbon nanofiber (CNF) membrane to obtain the bifunctional photocathode (CoFe-OVs@CNF) with both extraordinary photo-catalytic and electro-catalytic abilities. PFOA was highly mineralized on CoFe-OVs@CNF through the synergy of photocatalytic oxidation and electro-Fenton processes. Moreover, the energy consumption for degradation was generated from direct electro-oxidation of glucose as the clean power on anode (GFC). The possible mechanism and degradation pathway for PFOA mineralization was investigated in detail according to intermediate analysis, active species verification and the valence state change of Co and Fe on cathode. Besides, the toxicity evolution during PFOA degradation was also evaluated to deeper insight into risk assessment of intermedia products and relative toxicity, intending to prove the potential for practical elimination of PFOA and other toxicity recalcitrant pollutants in wastewater by GFC-SPEF system. [ABSTRACT FROM AUTHOR]

FexOy@FexOy/C nanoparticles with a soap-bubble-like shell have been synthesized, and the materials exhibit excellent Fenton catalytic performance. More importantly, FexOy@FexOy/C nanoparticles as catalysts and precursors could catalyze organic dye molecules to form iron oxide@organic dye polymer core–shell nanospheres. [ABSTRACT FROM AUTHOR]

Hypoxia was shown to be associated with an increased risk of Alzheimer's disease (AD). The effects of hypoxia on the development of AD pathology and spatial memory ability and the possible molecular mechanisms remain poorly understood. In this study, we demonstrate that rats exposed to a hypoxic condition (10% oxygen concentration) for 1, 2, 4 and 8 weeks (6 h each day) displayed spatial memory impairment and increased tau phosphorylation at Ser198/199/202, Thr205, Ser262, Ser396 and Ser404 in the hippocampus. Concomitantly, the levels of Tyr216-phosphorylated glycogen synthase kinase (GSK)-3β (activated form of GSK-3β) and Tyr307-phosphorylated protein phosphatase 2A (inactivated form of PP2A) were significantly increased in the hippocampus of the rats with 1, 2, 4 and 8 weeks of hypoxia exposure, while the levels of methylated PP2A (activated form of PP2A) were significantly decreased in the hippocampus of the rats with 4 and 8 weeks of hypoxia exposure. In addition, the content of malondialdehyde, an indicator of oxidative stress, was elevated, whereas the activity of superoxide dismutase was not significantly changed in the hippocampus of the rats exposed to hypoxia. Taken together, these data demonstrated that hypoxia induced tau hyperphosphorylation and memory impairment in rats, and that the increased tau phosphorylation could be attributed to activation of GSK-3β and inactivation of PP2A. These data suggest that interventions to improve hypoxia may be helpful to prevent the development of AD pathology and cognitive impairment. © 2014 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

It is desirable to prepare efficient catalysts to activate peroxymonosulfate (PMS) for catalytic degradation of organic pollutants in water. This study reported on the preparation of a promising PMS activator, magnetic NiCo layered double hydroxides (Fe 3 O 4 @NiCo LDHs) for naproxen (NPX) degradation in aqueous solution in the presence of PMS. Fe 3 O 4 @NiCo LDHs were prepared by simple hydrothermal method. The structure characterization showed that the layered structure of the material was obvious, and there was no obvious agglomeration phenomenon. Magnetic nanoparticles Fe 3 O 4 were loaded on the surface of Fe 3 O 4 @NiCo LDHs to provide magnetism, which facilitated subsequent separation and recovery. The catalytic tests were carried out in a thermostatic oscillator (20 ℃, 180 rpm) and the results indicated that Fe 3 O 4 @NiCo LDHs exhibited excellent catalytic performances for NPX in which 83.9% of NPX was removed within 20 min. Notably, Fe 3 O 4 @NiCo LDHs maintained good reusability and stability with removal efficiency of 78.1% even after five cycles. In addition, the potential applications of Fe 3 O 4 @NiCo LDHs for the degradation of NPX in actual water samples (the tap water and Yellow River water) were also investigated. [Display omitted] • Fe 3 O 4 @NiCo LDHs were able to degrade up to 83.9% of NPX in 20 min. • Fe 3 O 4 @NiCo LDHs exhibited excellent catalytic activity for activating PMS over a wide pH range. • Both non-free radicals and free radicals contributed to NPX degradation. • The degradation pathways of NPX were proposed. • Fe 3 O 4 @NiCo LDHs/PMS system exhibited great potential in practical application. [ABSTRACT FROM AUTHOR]