Porous metal oxides in the role of electrochemical CO_(2) reduction reaction

The global energy-related CO_(2) emissions have rapidly increased as the world economy heavily relied on fossil fuels.This paper explores the pressing challenge of CO_(2) emissions and highlights the role of porous metal oxide materials in the electrocatalytic reduction of CO_(2)(CO_(2)RR).The focus is on the development of robust and selective catalysts,particularly metal and metal-oxide-based materials.Porous metal oxides offer high surface area,enhancing the accessibility to active sites and improving reaction kinetics.The tunability of these materials allows for tailored catalytic behavior,targeting optimized reaction mechanisms for CO_(2)RR.The work also discusses the various synthesis strategies and identifies key structural and compositional features,addressing challenges like high overpotential,poor selectivity,and low stability.Based on these insights,we suggest avenues for future research on porous metal oxide materials for electrochemical CO_(2) reduction.

miRNA-137-5p improves spatial memory and cognition in Alzheimer's mice by targeting ubiquitin-specific peptidase 30

Background:Alzheimer’sdisease(AD)is a prevalent neurodegenerative disorder causing progressive dementia.Research suggests that microRNAs(miRNAs)could serve as biomarkers and therapeutic targets for AD.Reduced levels of miR-137 have been observed in the brains of AD patients,but its specific role and down stream mechanisms remain unclear.This study sought to examine the therapeutic potential of miR-137-5p agomir in alleviating cognitive dysfunction induced in AD models and explore its potential mechanisms.Methods:This study utilized bioinformatic analysis and a dual-l uciferase reporter assay to investigate the relationship between miR-137-5p and ubiquitin-specific peptidase 30(USP30).In vitro experiments were conducted using SH-SY5Y cells to assess the impact of miR-137-5p on Aβ1-42 neurotoxicity.In vivo experiments on AD mice evaluated the effects of miR-137-5p on cognition,Aβ1-42 deposition,Tau hyperphosphorylation,and neuronal apoptosis,as well as its influence on USP30 levels.Results:It was discovered that miR-137-5p mimics efficiently counteract Aβ1-42 neurotoxicity in SH-SY5Y cells,a protective effect that is negated by USP30 overexpression.In vivo experiments demonstrated that miR-137-5p enhances the cognition and mobility of AD mice,significantly reducing Aβ1-42 deposition,Tau hyperphosphorylation,and neuronal apoptosis within the hippocampus and cortex regions.Mechanistically,miR-137-5p significantly suppresses USP30 levels in mice,though USP30 overexpression partially buffers against miR-137-5p-i nduced AD symptom improvement.Conclusion:Our study proposes that miR-137-5p,by instigating the downregulation of USP30,has the potential to act as a novel and promising therapeutic target for AD.

Long cycle performance of NC@VN/MnO cathode for AZIBs based on Mn/V relay type collaboration

Aqueous zinc ion batteries(AZIBs) have received great attention because of their non-toxicity,high safety,low cost,high abundance,and high specific power.However,their specific capacity is still low compared with lithium ion battery,and current academic research interesting has been focused on developing new cathode materials with high specific capacity.In this study,a Mn/V hybrid polymer framework is designed by a simple self-polymerization scheme.During subsequent calcination,ultrafine VN quantum dots and MnO nanoparticles are generated in situ and stably encapsulated inside N-doped carbon(NC) shells to obtain a novel hybrid cathode NC@VN/MnO for AZIBs.According to the density functional theory(DFT) calculation,the hybrids of MnO and VN can generate both interfacial effects and built-in electric fields that significantly accelerate ion and electron transport by tuning the intrinsic electronic structure,thus enhancing electrochemical performance.A synergistic strategy of composition and structural design allows the rechargeable AZIBs to achieve low-cost and excellent long-cycle performance based on a relay type collaboration at different cycling stages.Consequently,the NC@VN/MnO cathode has output a capacity of 108.3 mA h g^(-1)after 12,000 cycles at 10 A g^(-1).These results clearly and fully demonstrate the advantages of the hybrid cathode NC@VN/MnO.

Simultaneous realization of high sulfur utilization and lithium dendrite-free via dual-effect kinetic regulation strategy toward lithium-sulfur batteries

With the high theoretical specific capacity and energy density,lithium-sulfur batteries(LSBs)have been intensively studied as promising candidates for energy storage devices.However,LSBs are largely hindered by inferior sulfur utilization and uncontrollable dendritic growth.Herein,a hierarchical functionalization strategy of stepwise catalytic-adsorption-conversion for sulfur species via the synergetic of the efficiently catalytic host cathode and light multifunctional interlayer has been proposed to concurrently address the issues arising on the dual sides of the LSBs.The multi-layer SnS_(2) micro-flowers embedded into the natural three-dimensional(3D)interconnected carbonized bacterial cellulose(CBC)nanofibers are fabricated as the sulfur host that provides numerous catalytic sites for the rapid catalytic conversion of sulfur species.Moreover,the distinctive CBC-based SnO_(2)-SnS_(2) heterostructure network accompanied high conductive carbon nanofibers as the multifunctional interlayer promotes the rapid anchoringdiffusion-conversion of lithium polysulfides,Li^(+)flux redistribution,and uniform Li deposition.LSBs equipped with our strategy exhibit a high reversible capacity of 1361.5 m A h g^(-1)at 0.2 C and superior cycling stability with an ultra-low capacity fading of 0.031%per cycle in 1000 cycles at 1.5 C and 0.046%at 3 C.A favorable specific capacity of 859.5 m A h g^(-1)at 0.3 C is achieved with a high sulfur mass loading of 5.2 mg cm^(-2),highlighting the potential of practical application.The rational design in this work can provide a feasible solution for high-performance LSBs and promote the development of advanced energy storage devices.

Recent progress in rate and cycling performance modifications of vanadium oxides cathode for lithium-ion batteries

The emergency of high-power electrical appliances has put forward higher requirements for the power density of lithium-ion batteries.Vanadium oxides with large theoretical capacities and high operating voltages are considered as prospective alternatives for the cathode of a new generation of lithium-ion batteries.However,the poor rate and cycling performance caused by the sluggish electrons/lithium transportation,irreversible phase changes,vanadium dissolution and large volume changes during the repeated lithium intercalation/deintercalation hinder their commercial development.Several optimizing routes have been carried out and extensively explored to address these problems.Taking V_(2)O_(5),VO_(2)(B),V_(6)O_(13),and V_(2)O_(3)as examples,this article reviewed their crystal structures and lithium storage reactions.Besides,recent progress in modification methods for the electrochemical insufficiencies of vanadium oxides,including nanostructure,heterogeneous atom doping,composite and self-supported electrodes has been systematically summarized and finally,the challenges for the industrialization of vanadium oxide cathodes and their development opportunities are proposed.

Histological observation on acellular nerve grafts co-cultured with Schwann cells for repairing defects of the sciatic nerve

BACKGROUND： Animal experiments and clinical studies about tissue engineering method applied to repair nerve injury mainly focus on seeking ideal artificial nerve grafts, nerve conduit and seed cells. Autologous nerve, allogeneic nerve and xenogeneic nerve are used to bridge nerve defects, it is one of the methods to promote the repair of nerve injury by culturing and growing Schwann cells, which can secrete various neurotrophic factor activities, in the grafts. OBJECTIVE ： To observe the effect of acellular nerve grafts co-cultured with Schwann cells in repairing defects of sciatic nerve. DESIGN： An observational comparative study.SETTING： Tissue Engineering Laboratory of China Medical University.MATERIALS： The experiment was carried out in the Tissue Engineering Laboratory of China Medical University between April 2004 and April 2005. Forty neonatal Sprague-Dawley rats of 5-8 days （either males or females） and 24 male Wistar rats of 180-220 g were provided by the experimental animal center of China Medical University. METHODS： ① Culture of Schwann cells： The bilateral sciatic nerves and branchial plexus were isolated from the 40 neonatal SD rats. The sciatic nerves were enzymatically digested with collagenase and dispase, isolatd, purified and cultured with the method of speed-difference adhersion, and identified with the SABC immunohistochemical method. ② Model establishment： In vitro Schwann cells were microinjected into 10-mm long acellular nerve grafts repairing a surgically created gap in the rat sciatic nerve. According to the different grafted methods, the animals were randomly divided into three groups： autografts （n=8）, acellular nerve grafts （n=8）, or acellular nerve grafts with Schwann cells （n=8）. ③ The regenerated nerve fiber number and average diameter of myeline sheath after culture were statistically anlayzed. MAIN OUTCOME MEASURES： ① The regenerated nerve ultrastructure, total number and density of myelinated nerve fibers, and the thickness of myeline sheath were observed under electron microscope. ② The images were processed with the Mias-1000 imaging analytical system to calculate the number of myelinated nerve fibers, and the thickness of myeline sheath. RESULTS： All the 24 Wistar rats were involved in the analysis of results. ① Results observed under transmission electron microscope： The regenerated myelinated nerve fibers in the group of acellular nerve grafts with Schwann cells were more even than those in the group of acellular nerve grafts, the number of myelinated nerve fibers and thickness of myelin sheath were close to those in the allografts group （P 〉 0.05）, but significantly different from those in the group of acellular nerve grafts （P 〈 0.05）. ② Results observed under scanning electron microscope： A great amount of Schwann cells with two polars were observed in the group of grafts with Schwann cells, the feature of cultured Schwann cells showed shoulder by shoulder, head to head. ③ The number of myelinated nerve fibers and thickness of myelin sheath analyzed by Mias-1000 imaging system in the group of acellular nerve grafts with Schwann cells were close to those in the autografts group （P 〉 0.05）, but significantly different from those in the group of acellular nerve grafts （P 〈 0.05）.CONCLUSION： Host axonal regeneration is significantly increased after implant of acellular nerve grafts. Acellular nerve grafts with Schwann cells offers a novel approach for repairing the gap of nerve defect.

Steady State Temperature Study on RF LDMOS with Structure Modification

This paper is devoted to temperature analysis on power RF LDMOS with different feature parameters of die thickness, pitch S length and finger width. The significance of these three parameters is determined from temperature comparison obtained by 3D Silvaco-Atlas device simulator. The first three simulations focus on temperature variation with the three factors at different output power density respectively. The results indicate that both the thinner die thickness and the broaden pitch S length have distinct advantages over the shorter finger width. The device, at the same time, exhibits higher temperature at a larger output power density. Simulations are further carried out on structure with combination of different pitch s length and die thickness at a large 1W/mm output power density and the temperature reduction reaches as high as 55%.

高熵二硼化物纳米颗粒的组分设计与催化降解抗生素研究

开发高熵硼化物材料的功能特性对于拓宽其在极端环境中的潜在应用至关重要.为此,本文通过调控材料的组分开发出具有高效催化性能的高熵二硼化物(HEB_(2))纳米颗粒:首先基于对HEB_(2)的尺寸差异因子、混合焓以及体系自蔓延燃烧模式的理论分析,我们采用一种简便、快速、低成本的燃烧合成方法合成了6种不同组分的HEB_(2)纳米颗粒;然后,通过对材料的组分进行调控实现了HEB_(2)纳米颗粒活化过硫酸盐降解抗生素的高效催化能力(四环素的最高去除效率可达93.5%).不同吸附位点的吸附能和差分电荷密度的第一性原理计算结果进一步证实了HEB_(2)优异的催化性能主要归因于Ti组元,而非高熵效应.此外,基于检测到的活性氧和计算的反应能垒,我们提出了HEB_(2)活化过硫酸盐降解抗生素的潜在催化机理.本研究不仅为HEB_(2)高效催化降解抗生素的组分设计提供了理论依据,而且显示出HEB_(2)在去除自然水体中新污染物方面的潜在应用前景.

Review on electrochemical carbon dioxide capture and transformation with bipolar membranes

Anthropogenic carbon dioxide(CO_(2))emission from the combustion of fossil fuels aggravates the global greenhouse effect.The implementation of CO_(2)capture and transformation technologies have recently received great attention for providing a pathway in dealing with global climate change.Among these technologies,electrochemical CO_(2)capture technology has attracted wide attention because of its environmental friendliness and flexible operating processes.Bipolar membranes(BPMs)are considered as one of the key components in electrochemical devices,especially for electrochemical CO_(2)reduction and electrodialysis devices.BPMs create an alkaline environment for CO_(2)capture and a stable pH environment for electrocatalysis on a single electrode.The key to CO_(2)capture in these devices is to understand the water dissociation mechanism occurring in BPMs,which could be used for optimizing the operating conditions for CO_(2)capture and transformation.In this paper,the references and technologies of electrochemical CO_(2)capture based on BPMs are reviewed in detail,thus the challenges and opportunities are also discussed for the development of more efficient,sustainable and practical CO_(2)capture and transformation based on BPMs.

Graphene-supported cobalt nanoparticles used to activate SiO_(2)-based anode for lithium-ion batteries

Although SiO_(2)-based anode is a strong competitor to supersede graphite anode for lithium-ion batteries,it still has problems such as low electrochemical activity, enormous loss of active lithium, and serious volume expansion. In order to solve these problems, we used a graphene network loaded with cobalt metal nanoparticles(rGO-Co) to coat SiO_(2) porous hollow spheres(SiO_(2)@rGO-Co). The construction of porous hollow structure and graphene network can shorten the lithium-ion(Li^(+)) diffusion distance and enhance the conductivity of the composite, which improves the electrochemical activity of SiO_(2) effectively. They also alleviate the volume expansion of the anode in the cycling process. Moreover,nano-scale cobalt metal particles dispersed on graphene catalyze the conversion reaction of SiO_(2) and activate the locked Li+in Li_(2)O through a reversible reaction, which improves the charge and discharge capacity of the anode. The capacity of SiO_(2)@rGO-Co reaches 370.4 m Ah/g after 100 cycles at 0.1 A/g,which is 6.19 times the capacity of pure SiO_(2)(59.8 mAh/g) under the same circumstance. What is more,its structure also exhibits excellent cycle stability, with a volume expansion rate of only 13.0% after 100 cycles at a current density of 0.1 A/g.

Relationship between the rise and fall of Loulan ancient city and centennial-scale climate events and cycles

The discovery of Loulan ancient city(LA)in the early 20th century has important significance for understanding the history of Western regions and the Silk Road civilization.The current academic community still has disputes on whether LA was the capital of Loulan Kingdom,the time of its rise,peak and decline,and the process,rate and driving mechanism of human activity change.This study uses the radio carbon dates(^(14)C)database of LA to reconstruct the history of the rise and fall of human activity,and finds that LA experienced more than~500 years from its rise to its peak and then to its decline:1)the city rose rapidly,and the population increased rapidly from~A.D.0 to 230;2)the city was prosperous and flourishing,and the intensity of human activity reached its peak from~A.D.160 to 340,especially in~A.D.230,when the population reached its peak;3)the city accelerated its decline,and the intensity of human activity decreased significantly,and the population shrank rapidly from~A.D.230 to 500;4)LA was completely abandoned after~A.D.560.The results of the ^(14)C dating database do not support that LA was the early capital of the Loulan Kingdom.By comparing the human activity record of LA with the existing high-resolution palaeoclimate records in the surrounding mountainous areas of the Tarim Basin and South Asia,it is found that the superposition of centennial-scale westerly circulation strength events and the~500-year cycle of the Indian monsoon jointly controlled the precipitation and meltwater(snow)supply of the mountains in the Tarim Basin,affecting the changes of surface runoff and oasis area in the basin,which is one of the important factors causing the rise and fall of LA.

The preservation effects of chitosan copolymers(gallic acid and protocatechuic acid)on sea bass(Lateolabrax japonicus)fillets

This study was aimed at preparing chitosan(CS)-phenolic acids copolymers to obtain better preservation effect in marine products.In this work,CS was grafted onto phenolic acids such as gallic acid(GA)and protocatechuic acid(PA)by a carbodiimide coupling method.The copolymers(CS-grafted-GA(CS-g-GA)and CS-grafted-PA(CS-g-PA))were further confirmed through physicochemical properties including ultraviolet-visible(UV-Vis)spectrophotography,fourier transform infrared(FTIR)spectrometry,differential scanning calorimetry(DSC)thermogram,rheological behaviour,scanning electron microscope(SEM)and antioxidant activity analysis.Subsequently,the effects of copolymers on preservation of refrigerated sea bass(Lateolabrax japonicus)fillets were investigated.The results showed that the CS-g-GA(110.82 mg GA/g)exhibited higher grafting rate than CS-g-PA(62.63 mg PA/g).According to the assessment of UV-Vis and FTIR spectrometry,both the GA and PA were grafted onto CS successfully.SEM analysis demonstrated that the microstructure of copolymers became irregular.Meanwhile,both the CS-g-GA and CS-g-PA copolymers displayed superior thermal stability,rheological properties and antioxidant capacity than the pure CS.Furthermore,the copolymers also revealed a significantly stronger preservation effect on sea bass fillets including inhibiting microbial growth and delaying the deterioration of color,texture and sensory quality.Therefore,CS-g-GA and CS-g-PA could be used as promising preservatives for seafood.

Gentiopicroside targets PAQR3 to activate the PI3K/AKT signaling pathway and ameliorate disordered glucose and lipid metabolism

The obstruction of post-insulin receptor signaling is the main mechanism of insulin-resistant diabetes.Progestin and adipoQ receptor 3(PAQR3),a key regulator of inflammation and metabolism,can negatively regulate the PI3 K/AKT signaling pathway.Here,we report that gentiopicroside(GPS),the main bioactive secoiridoid glycoside of Gentiana manshurica Kitagawa,decreased lipid synthesis and increased glucose utilization in palmitic acid(PA) treated HepG2 cells.Additionally,GPS improved glycolipid metabolism in streptozotocin(STZ) treated high-fat diet(HFD)-induced diabetic mice.Our findings revealed that GPS promoted the activation of the PI3 K/AKT axis by facilitating DNA-binding protein 2(DDB2)-mediated PAQR3 ubiquitinated degradation.Moreover,results of surface plasmon resonance(SPR),microscale thermophoresis(MST) and thermal shift assay(TSA) indicated that GPS directly binds to PAQR3.Results of molecular docking and cellular thermal shift assay(CETSA) revealed that GPS directly bound to the amino acids of the PAQR3 NH2-terminus including Leu40,Asp42,Glu69,Tyr125 and Ser129,and spatially inhibited the interaction between PAQR3 and the PI3 K catalytic subunit(P110α) to restore the PI3 K/AKT signaling pathway.In summary,our study identified GPS,which inhibits PAQR3 expression and directly targets PAQR3 to restore insulin signaling pathway,as a potential drug candidate for the treatment of diabetes.

Coastal blue carbon： Concept, study method, and the application to ecological restoration

Coastal blue carbon refers to the carbon taken from atmospheric CO2; fixed by advanced plants(including salt marsh,mangrove, and seagrass), phytoplankton, macroalgae, and marine calcifiers via the interaction of plants and microbes; and stored in nearshore sediments and soils; as well as the carbon transported from the coast to the ocean and ocean floor. The carbon sequestration capacity per unit area of coastal blue carbon is far greater than that of the terrestrial carbon pool. The mechanisms and controls of the carbon sink from salt marshes, mangroves, seagrasses, the aquaculture of shellfish and macroalgae, and the microbial carbon pump need to be further studied. The methods to quantify coastal blue carbon include carbon flux measurements, carbon pool measurements, manipulative experiments, and modeling. Restoring, conserving, and enhancing blue carbon will increase carbon sinks and produce carbon credits, which could be traded on the carbon market. The need to tackle climate change and implement China's commitment to cut carbon emissions requires us to improve studies on coastal blue carbon science and policy. The knowledge learned from coastal blue carbon improves the conservation and restoration of salt marshes,mangroves, and seagrasses; enhances the function of the microbial carbon pump; and promotes sustainable aquaculture, such as ocean ranching.

Dense ceramics with complex shape fabricated by 3D printing:A review

Three-dimensional(3D)printing technology is becoming a promising method for fabricating highly complex ceramics owing to the arbitrary design and the infinite combination of materials.Insufficient density is one of the main problems with 3D printed ceramics,but concentrated descriptions of making dense ceramics are scarce.This review specifically introduces the principles of the four 3D printing technologies and focuses on the parameters of each technology that affect the densification of 3D printed ceramics,such as the performance of raw materials and the interaction between energy and materials.The technical challenges and suggestions about how to achieve higher ceramic density are presented subsequently.The goal of the presented work is to comprehend the roles of critical parameters in the subsequent 3D printing process to prepare dense ceramics that can meet the practical applications.

Effect of the number of freeze-thaw cycles number on the quality of Pacific white shrimp (Litopenaeus vannamei): An emphasis on moisture migration and microstructure by LF-NMR and SEM

The objective of this study was to evaluate the effects of the number of freeze-thaw(F-T)cycles on moisture migration,protein degradation,microstructure and quality in Litopenaeus vannamei.The quality of samples with different F-T cycles were determined by low-field nuclear magnetic resonance(LF-NMR),magnetic resonance imaging(MRI)and scanning electron microscopy(SEM),combined with sodium dodecyl sulphate polyacrylamide gel electrophoresis(SDS-PAGE),texture properties analysis(TPA),color difference,polyphenol oxidase(PPO)activity,total volatile basic nitrogen(TVB-N),total viable count(TVC),and sensory evaluation.The results showed that F-T cycles caused a significantly increase in transverse relaxation time in T22 and T23 and a decreased brightness of pseudo-color diagram after 4 F-T cycles,indicating that water mobility increased as immobilized water was shifted to free water.The texture of samples declined as well,especially after 4 F-T cycles.The rapid growth of PPO activity caused a decrease in brightness(L*)and an increase in redness(a∗)after 3 F-T cycles.The increase of TVB-N,TVC,and sensory score explained the changes in shrimp quality which became obvious after 3 F-T cycles and unacceptable after 6 cycles.Meanwhile,fewer than 4 F-T cycles accelerated protein aggregation,while denaturation occurred after 4 cycles.Therefore,repeated F-T cycles could accelerate the changes of protein,microstructure,water distribution,and quality deterioration especially after 3 F-T cycles,with a threshold was 6 F-T cycles.

Antibacterial mechanism of Ginkgo biloba leaf extract when applied to Shewanella putrefaciens and Saprophytic staphylococcus

The antimicrobial mechanism of Ginkgo biloba leaf extracts(GBLE)when applied to predominant spoilage bacteria(Shewanella putrefaciens and Saprophytic staphylococcus)on refrigerated pomfret and minimal inhibitory concentrations(MICs)were measured by the plate counting method.GBLE at MIC and 2MIC were prepared in tryptic soy broth(TSB)medium and equivalent amounts of sterile distilled water were used in place of GBLE as a control group.The impact of GBLE on the growth of bacteria,the permeability of cell membrane,and cell wall were also investigated by growth curve of bacteria,alkaline phosphates activity(AKP),and electrical conductivity.A scanning electron microscope(SEM)was used to study the effects of GBLE on the cellular structure of S.putrefaciens and S.staphylococcus.The results showed that the MICs of GBLE when applied to S.putrefaciens and S.staphylococcus were 100 mg/mL,the inhibitory rates of MIC and 2MIC concentrations of GBLE when applied to S.putrefaciens were 36.11%and 100%,while 27.78%and 62.22%for S.staphylococcus.Meanwhile,GBLE inhibited the growth of S.putrefaciens and S.staphylococcus until the number of cells at 2MIC values decreased to 0 and 4.29 log CFU/mL,respectively,after 24 h.The electrical conductivity of bacteria increased with GBLE treatment,which was followed by an increased leakage of AKP.The SEM revealed that the structure of bacterial cells was destroyed and the bacteria began to be adhere to each other.The inhibition effect of GBLE when applied to S.putrefaciens and S.staphylococcus was related to the damage of cell membrane and cell wall.It was also revealed that GBLE damages the morphology of bacteria and had stronger effects on the cell membrane of S.putrefaciens than that of S.staphylococcus.

Pilot-scale experiments on multilevel contact oxidation treatment of poultry farm wastewater using saran lock carriers under different operation model

A pilot-scale multilevel contact oxidation reactors system, coupled with saran lock carriers,was applied for the treatment of poultry farm wastewater. The removal efficiencies of CODcr, ammonia, and the total nitrogen as well as the elimination performance of CODcr and total nitrogen along the three-level contact oxidation tanks under six designed operational models were investigated. Based on the performance of the nitrogen removal of the saran lock carriers and the distribution of anoxic–aerobic interspace under the suitable operation model, the mechanism of nitrogen removal of the system was also explored. The results revealed that the intermittent aeration under parallel model is the most suitable operation model, while the removal efficiencies of CODcr, ammonia, and the total nitrogen were 86.86%, 84.04%, and 80.96%, respectively. The effluent concentration of CODcr,ammonia, and the total nitrogen were 55.6 mg/L, 8.3 mg/L, and 12.0 mg/L, which satisfy both the discharge standard of pollutants for livestock and poultry breeding industry(GB18596–2001) and the first grade of the integrated wastewater discharge standard(GB 8978–1996). Moreover, the mechanism for the nitrogen removal should be attributed to the plenty of anoxic–aerobic interspaces of the biofilm and the three-dimensional spiral structure of the saran lock carriers, where the oxygen-deficient distribution was suitable for the happening of the simultaneous nitrification and denitrification process. Therefore, the multilevel contact oxidation tanks system is an effective pathway for the treatment of the poultry farm wastewater on the strength of a suitable operation model and novel carriers.

Methods for enhancing the capacity of electrode materials in low-temperature lithium-ion batteries

Lithium-ion batteries(LIBs)have evolved into the mainstream power source of ene rgy sto rage equipment by reason of their advantages such as high energy density,high power,long cycle life and less pollution.With the expansion of their applications in deep-sea exploration,aerospace and military equipment,special working conditions have placed higher demands on the low-temperature performance of LIBs.However,at low temperatures,the severe polarization and inferior electrochemical activity of electrode materials cause the acute capacity fading upon cycling,which greatly hindered the further development of LIBs.In this review,we summarize the recent important progress of LIBs in low-temperature operations and introduce the key methods and the related action mechanisms for enhancing the capacity of the various cathode and anode materials.It aims to promote the development of high-performance electrode materials and broaden the application range of LIBs.

MnS hollow microspheres combined with carbon nanotubes for enhanced performance sodium-ion battery anode

MnS as anode material for sodium-ion batteries(SIBs)has recently attracted great attention because of the high theoretical capacity,great natural abundance,and low cost.However,it suffers from inferior electrical conductivity and large volume expansion during the charge/discharge process,leading to tremendous damage of electrodes and subsequently fast capacity fading.To mitigate these issues,herein,a three-dimensional(3D)interlaced carbon nanotubes(CNTs)threaded into or between MnS hollow microspheres(hollow MnS/CNTs composite)has been designed and synthesized as an enhanced anode material.It can effectively improve the electrical conductivity,buffer the volume change,and maintain the integrity of the electrode during the charging and discharging process based on the synergistic interaction and the integrative structure.Therefore,when evaluated as anode for SIBs,the hollow MnS/CNTs electrode displays enhanced reve rsible capacity(275 mAh/g at 100 mA/g after 100 cycles),which is much better than that of pure MnS electrode(25 mAh/g at 100 mA/g after 100 cycles)prepared without the addition of CNTs.Even increasing the current density to 500 mA/g,the hollow MnS/CNTs electrode still delivers a five times higher reversible capacity than that of the pure MnS electrode.The rate performance of the hollow MnS/CNTs electrode is also superior to that of pure MnS electrode at various current densities from 50 mA/g to 1000 mA/g.