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The four-electron transfer process involved in anodic oxygen evolution reaction (OER) of electrocatalytic water splitting causes the sluggish kinetics and significantly limiting the efficiency of energy conversion. It's urgent to explore low-cost, efficient and stable electrocatalysts for OER. In the work, we design the nitrogen and molybdenum co-doped CoP with nanohoneycombs structure on three-dimensional (3D) nitrogen-doped porous graphene (N/Mo–CoP@NPG) as an efficient OER electrocatalyst. The N/Mo–CoP@NPG delivers the current density of 10 mA cm−2 at a low overpotential value of 201 mV in 1.0 M KOH, meanwhile the electrocatalytic activity shows no obvious degradation after 50 h. The NPG substrate provides plentiful ligaments for growth of N/Mo–CoP nanohoneycombs and 3D network for rapid electronic transfer. Additionally, doping N and Mo atoms into CoP synergistically modifies the micromorphology and electronic structure, benefiting the electrocatalytic ability. This work offers a promising strategy to improve the electrocatalytic activity of transition metal phosphides.

A high-quality and centimeter-level three-dimensional (3D) nitrogen-doped graphene (NG) nanonetwork is synthesized via a chemical vapor deposition method to serve as a substrate and a current colle...

In order to cope with the problem of insufficient lithium metal reserves, sodium ion batteries (SIBs) are proposed and extensively studied for the next-generation batteries. In our work, hierarchical NiCo2Se4 nanoneedles/nanosheets are deposited on the skeleton of N-doped three dimensional porous graphene (NPG) by a convenient solvothermal method and subsequent gas-phase selenization process. Compared with NiCo2Se4 powder, the optimized NiCo2Se4/N-doped porous graphene composite (denoted as NCS@NPG) as self-supporting anode exhibits the excellent electrode activity for SIBs, with a specific capacity of 500 mAh/g and 257 mAh/g at a current density of 0.2 A/g and 6.4 A/g, respectively. The high specific capacity as well as rate capacity can be attributed to the three-dimensional graphene skeleton with high electrical conductivity and pore structure, which provides convenient ion and electron transmission channels.

A facile two-step approach is employed to prepare novel Ni2P@CNT hybrid photocatalyst, which is assembled by nickel phosphide (Ni2P) nanoparticles on the inner wall of graphitic carbon nitride tube (CNT). This unique microstructure endows Ni2P@CNT with close interfacial interaction, promotes efficient separation of photoexcited charge carriers and provides enriched sites for photocatalytic reaction. Moreover, the hybrid system is found to exhibit more superior photocatalytic hydrogen evolution activity than pure CNT and Pt-decorated CNT (Pt@CNT). As a consequence, the work illustrates the essential role of experimental process on the final morphology and performance, which is expected to pave a new method to construct various kind of excellent photocatalyst.

Zinc-vanadium oxides have been attracting increasing consideration as anode materials for lithium/sodium-ion batteries (LIBs and SIBs) recently. Present applications are hampered by issues, including their inferior electric conductivity and enormous volume variation. Herein, nitrogen-doped carbon wrapped Zn3V3O8 (Zn3V3O8/NC) microspheres composed of abundant nanosheets were developed as an anode material by a self-assembly strategy and subsequent surface decoration. The resulting Zn3V3O8/NC porous hybrid exhibited a high specific capacity, impressive rate capability, and long-term cycling stability for both LIBs and SIBs. Notably, the superior electrochemical properties could be assigned to novel meso/microporous features, hybrid nitrogen-doped carbon, and mixed storage mechanisms.

Molybdenum dioxides (MoO2) featuring low cost and high theoretical capacity endow them competitive anode materials for lithium-ion batteries (LIBs)/sodium-ion batteries (SIBs). However, the low electrical conductivity and severe volume expansion occurring during the ion insertion/extraction process hamper their practical application. Herein, a novel dual-annealing design has been developed for the synthesis of highly uniform MoO2 nanopopcorns decorated with nitrogen-doped carbon shell (MoO2/NC). Owing to the unique structural characteristics and vital amorphous NC component, the MoO2/NC nanopopcorn hybrid composite exhibits stabilized charge storage capacity of 1073 mAh g-1 after 200 cycles for LIBs, while 301 mAh g-1 after 500 cycles for SIBs at 0.5 A g-1. Furthermore, when the current density increases to 5 A g-1, the specific capacity could still maintain 630 mAh g-1 and 174 mAh g-1 for LIBs and SIBs, respectively, which disclose the outstanding rate capability of MoO2/NC nanopopcorn anode.

It is extremely necessary to develop highly efficient and low-cost non-noble metal electrocatalysts for hydrogen evolution reaction (HER) under a pH-universal condition in the realm of sustainable energy. Herein, we have successfully prepared phosphorus doped Fe3O4 nanoflowers on three-dimensional porous graphene (denoted as P–Fe3O4@3DG) via a simple hydrothermal and low-temperature phosphating reaction. The P–Fe3O4@3DG hybrid composite not only demonstrates superior performance for HER in 1.0 M KOH with low overpotential (123 mV at 10 mA/cm2), small Tafel slope (65 mV/dec), and outstanding durability exceeding 50 h, but also exhibits satisfying performances under neutral and acidic medium as well. The 3D graphene foam with large porosity, high conductivity, and robust skeleton conduces to more active sites, and faster electron and ion transportation. The phosphorus dopant provides low Gibbs free energy and ability of binging H+. The synergistic effect of 3DG substrate and P–Fe3O4 active material both accelerates the catalytic activity of Fe-based hybrid composite for HER.

α-Phase molybdenum trioxide (α-MoO3) is one of the promising anode materials for lithium storage due to its high theoretical capacity and unique intercalation reaction mechanism. Herein, through an efficient step-by-step solvothermal synthesis strategy, multi-layered MoO3 nanosheets are encapsulated by nitrogen-doped carbon (NC) and ultrathin TiO2 double-shells to obtain hierarchical core-shell nanospheres (MoO3@TiO2@NC). The unique nanostructure enables shortening the Li+ diffusion distance, buffer the volume change during the intercalation/deintercalation process, and increase the active sites for the electrochemical reaction. Based on the hierarchical nanostructure and the synergistic effect of each component, the MoO3@TiO2@NC electrode exhibits a high Li+ storage capacity around 979.6 mA h g-1 after 200 cycles at 0.2 A g-1, a stable cycle performance of 800.3 mA h g-1 at 1 A g-1 after 700 cycles and an excellent rate capability of 418.0 mA h g-1 at 5 A g-1. Furthermore, the MoO3@TiO2@NC-based coin-type full cell with a commercial LiNi1/3Mn1/3Co1/3O2 cathode exhibited a good cycling stability at 0.2 A g-1 for 100 cycles (∼190 mA h g-1) and rate capability (134 mA h g-1 at 5 A g-1).

The preparation of an Earth-abundant, highly efficient and durable bifunctional electrocatalyst for water electrolysis is indispensable and in great demand. Herein, a bifunctional catalyst, cobalt–chromium phosphide (Co2Cr1-P) merged with a substrate of three-dimensional graphene foam (3DGF), was reported. The Co2Cr1-P@3DGF composite demonstrates remarkable electrocatalytic activities for the production of hydrogen and oxygen in 1.0 M KOH, which only requires a low overpotential of 118 and 270 mV to afford 10 mA cm−2, respectively. Additionally, when applying Co2Cr1-P@3DGF as a catalytic electrode for alkaline overall water splitting, the demanded cell voltage at 10 mA cm−2 is merely 1.56 V. The superior performance is attributable to the incorporation of the Cr element into CoP and the good conductivity of the 3D graphene network substrate.

Novel carbon self-doped graphitic carbon nitride tube (denoted as C-CNT) was fabricated by the means of a facile in situ solvothermal method with melamine and glucose as precursor and additive, respectively. The C-CNT not only remained unique hexagonal tubular structure obtained from supramolecular self-assembly method, but also introduced aromatic carbon into CN framework under the glucose-assisted hydrothermal conditions. The as-prepared C-CNT exposed abundant nitrogen defects and dramatically improved the valid separation of photoexcited charge carriers, hence achieving excellent photocatalytic hydrogen evolution activity (32.3 μmol h−1, λ > 420 nm), which was up to 4.24 and 12-folds higher than pristine carbon nitride tube (CNT) and traditional bulk counterpart (BCN), respectively. Therefore, this work highlights an assisted hydrothermal approach to successfully prepare carbon-rich graphitic carbon nitride with hexagonal tubular structure.

Zinc-vanadium oxides have been attracting increasing consideration as anode materials for lithium/sodium-ion batteries (LIBs and SIBs) recently. Present applications are hampered by issues, including their inferior electric conductivity and enormous volume variation. Herein, nitrogen-doped carbon wrapped Zn

In order to cope with the problem of insufficient lithium metal reserves, sodium ion batteries (SIBs) are proposed and extensively studied for the next-generation batteries. In our work, hierarchical NiCo

α-Phase molybdenum trioxide (α-MoO

The impact of different Helicobacter pylori (H. pylori) status (H. pylori negative, H. pylori eradication and H. pylori persistence) on the development of metachronous gastric lesions after endoscopic resection of early gastric cancer is not well defined. Thus, a systematic review and meta-analysis was performed to investigate this relationship. Two authors independently searched the electronic databases (Pubmed, Embase, the Cochrane Library and Web of Science) through March 2018, without language restriction. Pooled risk ratio for metachronous gastric lesions with regard to H. pylori status was calculated using fixed- or random-effects models, and heterogeneity and publication bias were also measured. 20 eligible studies were finally identified in systematic review, and 17 out of 20 studies were further included in meta-analysis. H. pylori eradication was associated with overall 50% lower odds of metachronous events (RR = 0.50; 95 % CI 0.41-0.61). Pooled risk ratios for metachronous gastric neoplasm were 0.85 (95 % CI 0.43-1.68) between H. pylori-eradicated and -negative patients, and 0.63 (95 % CI 0.35-1.12) between H. pylori-negative and -persistent patients, respectively. In conclusion, based on the best available evidence, eradication of H. pylori can provide protection against secondary gastric neoplasm, and this quantitative benefit seemed greater than among asymptomatic individuals. Metachronous risk seems comparable between H. pylori-eradicated and -negative population, or between H. pylori-negative and -persistent patients.

Molybdenum dioxides (MoO

The design of high-performance anodes is crucial for the whole for lithium-ion batteries (LIBs). Binary transition metal oxides (bi-TMOs), especially cobalt vanadates featuring high theoretical lithium storage capacity endow them promising anode materials. However, low electric conductivity as well as tremendous volume change occurring during the process of de−/lithiation restrict their commercialization. Herein, the as-devised novel spinel Co2VO4 yolk-shell microspheres coated with nitrogen-doped carbon shell (Co2VO4@NC) were synthesized by the method of a self-templated solvothermal preparation and following in-situ pyrolysis of polydopamine (PDA) film, which demonstrates excellent properties as anode for LIBs by virtue of the unique spinel structural characteristics, mixed lithium storage mechanism, micro/nanolization of the yolk-shell structure and vital amorphous NC component. In detail, the unique Co2VO4@NC electrode displays the high Li ion storage capacity (1255 mAh g−1 at 0.2 A g−1), the superior cycling stability (1227 mAh g−1 at 0.5 A g−1 after 400 cycles) as well as outstanding reversible capability (remaining 862 mAh g−1 when return to 0.1 A g−1 from 5 A g−1, larger than initial 796 mAh g−1).

In the work, the porous FeMnO3 nanocages combined with nitrogen-doped carbon shells (FeMnO3@NC) are studied as the anode material for lithium ion batteries (LIBs). The FeMnO3@NC composite can inherit the nanocage-like structure of Prussian blue analogue (PBA) precursor, which is capable of buffering volume expansion and promoting the penetration of electrolyte. The nitrogen-doped carbon layer enhances the electronic transmission and structure stability of perovskite-type FeMnO3. Therefore, the composite electrode exhibits superior electrochemical performances, including desirable rate capability, excellent cycling stability and high capacity of ~1008 mAh g−1 after 500 cycles at 1 A g−1. Considering the features of FeMnO3@NC composite with environmental friendliness, low cost, and outstanding lithium ion storage performance, it is expected to become a promising material for new hybrid energy storage devices.

This study focused on using cetyl trimethyl ammonium bromide (CTAB) modified Aspergillus versicolor biomass (AVB) as biosorbent to remove reactive black 5 (RB5). Effect parameters for biosorption performance including CTAB concentration, pH and contact time were investigated. Removal efficiency of RB5 by 1.5% CTAB modified AVB attained above 98% under contact time of 420 min, 200 mg/L as initial dye concentration and for pH 2. The dynamic experimental data fitted well to pseudo-second-order kinetic. Biosorption isotherm data followed Langmuir isotherm model and the maximum biosorption capacity was 227.27 mg/g. In addition, the effects of some co-contaminants in dye wastewater including mineral salts (NaCl, Na 2 SO 4 ), sodium dodecyl sulfate (SDS) and heavy metals (Zn 2+ , Ni 2+ and Pb 2+ ) on biosorption capacity and kinetics were investigated. Results demonstrated that salts and SDS would reduce biosorption capacity except heavy metals, they all would decrease the biosorption rate in different extent. The high biosorption performance for the modified AVB was due to the increased BET surface area and functional groups after CTAB modification. In summary, the modified AVB is cost effective, environmentally friendly and regenerable, which makes it an excellent material for RB5 removal from dye wastewater.

The spinel MnCo2O4 characterizing metallic synergistic effect and multi-electron transfer is a promising anode material in lithium-ion batteries (LIBs) fields. In the work, the MnCo2O4 porous nanospheres are prepared in virtue of self-assembly ability of glycerol micro-emulsion and subsequent annealing under appropriate temperature. Polypyrrole pyrolytic carbon is introduced to hybridize with low-dimension MnCo2O4 material to settle the common problems of intrinsic low electrical conductivity and severe volume expansion of electrode material. Because of hierarchical porous structure, polypyrrole pyrolytic carbon and metallic synergistic effect, the electrode delivers higher specific capacity, better rate capability and long-term cycling stability compared to several spinel-type oxides/carbon composites.

The nanostructured hybrids composed of binary transition metal oxides (bi-TMOs) have emerged as promising anode materials in lithium ion batteries (LIBs) because of their unique physicochemical properties. Herein, we report ZnO/CoO mesoporous microspheres encapsulated by nitrogen-doped carbon shells (ZnO–CoO@NC) via self-templated solvothermal synthesis and subsequent in-situ pyrolysis of polypyrrole. The core of nanohybrid is derived from single-phase ZnCo2O4 microspheres and consists of uniform two-phase ZnO/CoO nanocrystals with interparticle mesopores. By virtue of the conductive layer of N-doped carbon and the interaction between mixed ZnO and CoO, the ZnO–CoO@NC mesoporous microspheres manifest the superior lithium storage properties as anode for LIBs, which exhibits the high Li+ storage capacity and the excellent cycling performance (1457 mAh g−1 at 0.5 A g−1 after 500 cycles), along with the competitive rate capability (381 mAh g−1 at 5 A g−1).

A facile strategy for the synthesis of well-conductive Ag nanoparticles decorated mesoporous Co3O4 nanoboxes is reported. The fabrication processes involve a thermal annealing of Co3[Co(CN)6]2 Prussian blue analogue (PBA) template and subsequent in-situ chemical reductive deposition of Ag coating. The obtained electrically conductive Ag-coated Co3O4 hollow nanoboxes (Ag@Co3O4 HNBs) electrodes possess remarkable lithium storage performances as anodes including high reversible capacity, improved rate capability and long-life cyclability than bare Co3O4 HNBs. The optimized Ag@Co3O4 HNB anodes demonstrate high lithium storage capacity of 1015 mA h g−1 at 200 mA g−1, distinguished reactivated capacity (1115 mA h g−1 at 1 A g−1) and decent rate capability (339 mAh g−1 at 5A g−1). The key points of improved electrochemical behaviors for Ag@Co3O4 composites are due to the formation of Co3O4 hierarchical nanostructure with high porosity as well as the enhancement of electrical conductivity introduced by Ag nanoparticles films.

Manganese monoxide (MnO) has emerged as a promising anode material in lithium-ion batteries (LIBs) due to its large lithiation capacity, low voltage hysteresis and environmental friendliness. In this work, we have developed the nitrogen-doped carbon coated MnO porous microspheres (MnO@NC), which consist of small nanocrystals with interparticle mesopores via a self-templated solvothermal synthesis and subsequent in-situ pyrolysis of polypyrrole precursors. By virtue of the conductive outer layer of nitrogen-doped carbon (NC) and the abundant inner mesopores, the hierarchical MnO@NC porous microspheres manifest the superior lithium storage properties as anode for LIBs. In detail, the optimized MnO@NC electrode delivers a high initial discharge capacity of 1037 mAh g−1 at 0.2 A g−1, remains the discharge capacity of 890 mAh g−1 at 1A g−1 after 500 cycles, indicates the outstanding rate capability with a specific capacity of 450 mAh g−1 at 5A g−1.

It is well known that Helicobacter pylori (H. pylori) is not the only indigenous bacterium in the stomach, as numerous studies have revealed that the gastric microbiota contributes to the pathogenesis of gastric disease. However, the correlation between the gastric bacterial flora and gastritis is unclear. By comparing differences in viable gastric bacteria between a gastritis group and a healthy group, we examined the potential species related to chronic gastritis. We collected juice and mucosa samples from 103 consecutive patients and identified 81 species by culturing and matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS). The positive rates of Streptococcus and Neisseria were markedly higher in the gastritis group than those in the normal group, suggesting that certain bacterial species may play vital roles in the development of gastritis rather than acting as transient microbes. This finding can be applied to the diagnosis and treatment of chronic gastritis as evidence supporting non-Helicobacter pylori infection-related gastritis.

There were some studies both in vivo and in vitro, which showed some toxic effects of Cu-NPs. This study focused on the effect of these materials on rats’ hippocampal synaptic plasticity and spatial cognition, and the possible mechanism. In this research, 16 adult male Wistar rats were randomly divided into two groups: control group and Cu-NPs group. After intranasal application of Cu-NPs (3mg/kg) for two weeks, Morris water maze (MWM) was applied to evaluate the spatial learning and memory ability followed by long-term potentiation (LTP) to assess the hippocampal synaptic plasticity. The results showed that when compared with the control group, both results of MWM and LTP were impaired in Cu-NPs group. The histology analysis showed an abnormal morphology of hippocampal neurons in rats of Cu-NPs group. The content of reactive oxygen species (ROS) increased in hippocampus homogenate in Cu-NPs group, while the glutathione peroxidase (GSH-Px) level was reduced in this group. All the results above showed that Cu-NPs can cause damage to rats’ hippocampal synaptic plasticity and spatial cognition. The excessive ROS and decrease in GSH-Px levels can cause severe oxidative stress, which may account for the influence by Cu-NPs.

Bacterial cellulose (BC) membranes with shape-memory properties allow the rapid preparation of artificial small-diameter blood vessels when combined with microfluidics-based patterning with multiple types of cells. Lyophilization of a wet multilayered rolled BC tube endows it with memory to recover its tubular shape after unrolling. The unrolling of the BC tube yields a flat membrane, and subsequent patterning with endothelial cells, smooth muscle cells, and fibroblast cells is carried out by microfluidics. The cell-laden BC membrane is then rerolled into a multilayered tube. The different cells constituting multiple layers on the tubular wall can imitate blood vessels in vitro. The BC tubes (2 mm) without cell modification, when implanted into the carotid artery of a rabbit, maintain thrombus-free patency 21 d after implantation. This study provides a novel strategy for the rapid construction of multilayered small-diameter BC tubes which may be further developed for potential applications as artificial blood vessels.