Alkali metals(Li,Na,and K)are promising candidates for high-performance rechargeable alkali metal battery anodes due to their high theoretical specific capacity and low electrochemical potential.However,the actual app...Alkali metals(Li,Na,and K)are promising candidates for high-performance rechargeable alkali metal battery anodes due to their high theoretical specific capacity and low electrochemical potential.However,the actual application of alkali metal anodes is impeded by the challenges of alkali metals,including their high chemical reactivity,uncontrolled dendrite growth,unstable solid electrolyte interphase,and infinite volume expansion during cycling processes.Introducing carbon nanotube-based nanomaterials in alkali metal anodesis an effective solution to these issues.These nanomaterials have attracted widespread attention owing to their unique properties,such as their high specific surface area,superior electronic conductivity,and excellent mechanical stability.Considering the rapidly growing research enthusiasm for this topic in the last several years,we review recent progress on the application of carbon nanotube-based nanomaterials in stable and dendrite-free alkali metal anodes.The merits and issues of alkali metal anodes,as well as their stabilizing strategies are summarized.Furthermore,the relationships among methods of synthesis,nano-or microstructures,and electrochemical properties of carbon nanotube-based alkali metal anodes are systematically discussed.In addition,advanced characterization technologies on the reaction mechanism of carbon nanotube-based nanomaterials in alkali metal anodes are also reviewed.Finally,the challenges and prospects for future study and applications of carbon nanotube-based AMAs in high-performance alkali metal batteries are discussed.展开更多
Gas hydrate drilling expeditions in the Pearl River Mouth Basin,South China Sea,have identified concentrated gas hydrates with variable thickness.Moreover,free gas and the coexistence of gas hydrate and free gas have ...Gas hydrate drilling expeditions in the Pearl River Mouth Basin,South China Sea,have identified concentrated gas hydrates with variable thickness.Moreover,free gas and the coexistence of gas hydrate and free gas have been confirmed by logging,coring,and production tests in the foraminifera-rich silty sediments with complex bottom-simulating reflectors(BSRs).The broad-band processing is conducted on conventional three-dimensional(3D)seismic data to improve the image and detection accuracy of gas hydratebearing layers and delineate the saturation and thickness of gas hydrate-and free gas-bearing sediments.Several geophysical attributes extracted along the base of the gas hydrate stability zone are used to demonstrate the variable distribution and the controlling factors for the differential enrichment of gas hydrate.The inverted gas hydrate saturation at the production zone is over 40% with a thickness of 90 m,showing the interbedded distribution with different boundaries between gas hydrate-and free gas-bearing layers.However,the gas hydrate saturation value at the adjacent canyon is 70%,with 30-m-thick patches and linear features.The lithological and fault controls on gas hydrate and free gas distributions are demonstrated by tracing each gas hydrate-bearing layer.Moreover,the BSR depths based on broad-band reprocessed 3D seismic data not only exhibit variations due to small-scale topographic changes caused by seafloor sedimentation and erosion but also show the upward shift of BSR and the blocky distribution of the coexistence of gas hydrate and free gas in the Pearl River Mouth Basin.展开更多
This paper is concerned with the Navier-Stokes/Allen-Cahn system,which is used to model the dynamics of immiscible two-phase flows.We consider a 1D free boundary problem and assume that the viscosity coefficient depen...This paper is concerned with the Navier-Stokes/Allen-Cahn system,which is used to model the dynamics of immiscible two-phase flows.We consider a 1D free boundary problem and assume that the viscosity coefficient depends on the density in the form ofη(ρ)=ρ^(α).The existence of unique global H^(2m)-solutions(m∈N)to the free boundary problem is proven for when 0<α<1/4.Furthermore,we obtain the global C^(∞)-solutions if the initial data is smooth.展开更多
Free amino acid(FAA)is the important component of vinegar that infl uences quality perception and consumer acceptance.FAA is one of the major metabolites produced by microorganisms;however,the microbial metabolic netw...Free amino acid(FAA)is the important component of vinegar that infl uences quality perception and consumer acceptance.FAA is one of the major metabolites produced by microorganisms;however,the microbial metabolic network on FAA biosynthesis remains unclear.Through metagenomic analysis,this work aimed to elucidate the roles of microbes in FAA biosynthesis during Monascus rice vinegar fermentation.Taxonomic profiles from functional analyses showed 14 dominant genera with high contributions to the metabolism pathways.The metabolic network for FAA biosynthesis was then constructed,and the microbial distribution in different metabolic pathways was illuminated.The results revealed that 5 functional genera were closely involved in FAA biosynthesis.This study illuminated the metabolic roles of microorganisms in FAA biosynthesis and provided crucial insights into the functional attributes of microbiota in vinegar fermentation.展开更多
Nitrogen(N),phosphorus(P)and carbon(C)are essential nutrients for rice growth and development,but the response of nutrient absorption by rice plants to different types of nitrogen fertilizer(N-fertilizer)under saline-...Nitrogen(N),phosphorus(P)and carbon(C)are essential nutrients for rice growth and development,but the response of nutrient absorption by rice plants to different types of nitrogen fertilizer(N-fertilizer)under saline-alkali conditions is unclear.This study conducted a 147-day field-scale experiment to evaluate rice biomass and nutrient absorption capacity with five N-fertilizer applications.The results showed that the biomass.展开更多
1.Introduction and context Enormous emphasis is currently being paid to the decarbonization of the global built environment as a leading priority for the engineering community and related industrial sectors[1].One of ...1.Introduction and context Enormous emphasis is currently being paid to the decarbonization of the global built environment as a leading priority for the engineering community and related industrial sectors[1].One of the main contributors to the overall emissions footprint of the built environment-and thus a cornerstone of efforts to achieve decarbonization-is the emissions profile of construction materials during their production and utilization.The cement and concrete sector is the largest-volume contributor to the emissions incurred in meeting the world’s construction material needs and is therefore targeted in the discussion of the deep,rapid decarbonization that must be achieved in order to minimize irreversible damage to the Earth and its ecosystems.展开更多
Viologens known as a kind of promising negolyte materials for aqueous organic redox flow batteries,face a critical stability challenge due to the S_N2 nucleophilic attack by hydroxide ions(OH-)during the battery cycli...Viologens known as a kind of promising negolyte materials for aqueous organic redox flow batteries,face a critical stability challenge due to the S_N2 nucleophilic attack by hydroxide ions(OH-)during the battery cycling.In this work,a N-cyclic quaternary ammonium-grafted viologen molecule,viz.1,1'-bis(4,4'-dime thylpiperidiniumyl)-4,4'-bipyridinium tetrachloride((DBPPy)Cl_(4)),is developed by the molecular engineering strategy.The obtained(DBPPy)Cl_(4) molecule shows a decent solubility of 1.84 M and a redox potential of-0.52 V vs.Ag/AgCl,Experimental and theoretical results reveal that the grafted N-cyclic quaternary ammonium groups act as the steric hindrance to prevent nucleophilic attack by OH~-,increasing the alkali resistance of the electroactive molecule.The symmetrical battery with 0.50 M(DBPPy)Cl4shows negligible decay during the 13-day cycling test.As demonstration,the flow battery utilizing 1.0 M(DBPPy)Cl_(4) as the negolyte and 1-(1-oxyl-2,2',6,6'-tetramethylpiperidin-4-yl)-1'-(3-(trimethylammonio)propyl)-4,4'-bipyridinium trichloride as the posolyte exhibits a high capacity retention rate of 99.99%per cycle at 60 mA cm^(-2).展开更多
The existence of alkali metals in fl ue gases originating from stationary sources can result in catalyst deactivation in the low-temperature selective catalytic reduction(SCR)of nitrogen oxides(NO_(x)).It is widely ac...The existence of alkali metals in fl ue gases originating from stationary sources can result in catalyst deactivation in the low-temperature selective catalytic reduction(SCR)of nitrogen oxides(NO_(x)).It is widely accepted that alkali metal poisoning causes damage to the acidic sites of catalysts.Therefore,in this study,a series of CoMn catalysts doped with heteropolyacids(HPAs)were prepared using the coprecipitation method.Among these,CoMnHPMo exhibited superior catalytic performance for SCR and over 95%NO_(x) conversion at 150-300.Moreover,it exhibited excellent catalytic activity and stability after alkali poisoning,demonstrating outstanding alkali metal resistance.The characterization indicated that HPMo increased the specifi c surface area of the catalyst,which provided abundant adsorption sites for NO_(x) and NH_(3).Comparing catalysts before and after poisoning,CoMnHPMo enhanced its alkali metal resistance by sacrifi cing Brønsted acid sites to protect its Lewis acid sites.In situ DRIFTS was used to study the reaction pathways of the catalysts.The results showed that CoMnHPMo maintained high NH_(3) adsorption capacity after K poisoning and then reacted rapidly with NO intermediates to ensure that the active sites were not covered.Consequently,SCR performance was ensured even after alkali metal poisoning.In sum-mary,this research proposed a simple method for the design of an alkali-resistant NH_(3)-SCR catalyst with high activity at low temperatures.展开更多
Internal curing agents (ICA) based on super absorbent polymer have poor alkali tolerance and reduce the early strength of concrete.An alkali tolerate internal curing agent (CAA-ICA) was designed and prepared by using ...Internal curing agents (ICA) based on super absorbent polymer have poor alkali tolerance and reduce the early strength of concrete.An alkali tolerate internal curing agent (CAA-ICA) was designed and prepared by using sodium carboxymethyl starch (CMS) with high hydrophilicity,acrylic acid (AA) containing anionic carboxylic group and acrylamide (AM) containing non-ionic amide group as the main raw materials.The results show that the ratio of CAA-ICA alkali absorption solution is higher than that existing ICA,which solves the low water absorption ratio of the ICA in alkali environment.The water absorption ratio of CAA-ICA in saturated Ca(OH)_(2) solution is 95.8 g·g^(-1),and the alkali tolerance coefficient is 3.4.The application of CAA-ICA in cement-based materials can increase the internal relative humidity and miniaturize the pore structure.The compressive strength of mortar increases up to 12.95%at 28 d,which provids a solution to overcome the reduction of the early strength.展开更多
High-energy density lithium-ion batteries(LIBs)with layered high-nickel oxide cathodes(LiNi_(x)Co_(y)Mn_(1-x-y)O_(2),x≥0.8)show great promise in consumer electronics and vehicular applications.However,LiNi_(x)Co_(y)M...High-energy density lithium-ion batteries(LIBs)with layered high-nickel oxide cathodes(LiNi_(x)Co_(y)Mn_(1-x-y)O_(2),x≥0.8)show great promise in consumer electronics and vehicular applications.However,LiNi_(x)Co_(y)Mn_(1-x-y)O_(2)faces challenges related to capacity decay caused by residual alkalis owing to high sensitivity to air.To address this issue,we propose a hazardous substances upcycling method that fundamentally mitigates alkali content and concurrently induces the emergence of an anti-air-sensitive layer on the cathode surface.Through the neutralization of polyacrylic acid(PAA)with residual alkalis and then coupling it with 3-aminopropyl triethoxysilane(KH550),a stable and ion-conductive cross-linked polymer layer is in situ integrated into the LiNi_(0.89)Co_(0.06)Mn_(0.05)O_(2)(NCM)cathode.Our characterization and measurements demonstrate its effectiveness.The NCM material exhibits impressive cycling performance,retaining 88.4%of its capacity after 200 cycles at 5 C and achieving an extraordinary specific capacity of 170.0 mA h g^(-1) at 10 C.Importantly,this layer on the NCM efficiently suppresses unfavorable phase transitions,severe electrolyte degradation,and CO_(2)gas evolution,while maintaining commendable resistance to air exposure.This surface modification strategy shows widespread potential for creating air-stable LiNi_(x)Co_(y)Mn_(1-x-y)O_(2)cathodes,thereby advancing high-performance LIBs.展开更多
This paper is devoted to the study of the shape of the free boundary for a threedimensional axisymmetric incompressible impinging jet.To be more precise,we will show that the free boundary is convex to the fluid,provi...This paper is devoted to the study of the shape of the free boundary for a threedimensional axisymmetric incompressible impinging jet.To be more precise,we will show that the free boundary is convex to the fluid,provided that the uneven ground is concave to the fluid.展开更多
This study focuses on treating Guadua angustifolia bamboo fibers to enhance their properties for reinforcement applications in composite materials.Chemical(alkali)and physical(dry etching plasma)treatments were used s...This study focuses on treating Guadua angustifolia bamboo fibers to enhance their properties for reinforcement applications in composite materials.Chemical(alkali)and physical(dry etching plasma)treatments were used separately to augment compatibility of Guadua angustifolia fibers with various composite matrices.The influence of these treatments on the fibers’performance,chemical composition,and surface morphology were analyzed.Statistical analysis indicated that alkali treatments reduced the tensile modulus of elasticity and strength of fibers by up to 40%and 20%,respectively,whereas plasma treatments maintain the fibers’mechanical performance.FTIR spectroscopy revealed significant alterations in chemical composition due to alkali treatments,while plasma-treated fibers showed minimal changes.Surface examination through Scanning Electron Microscopy(SEM)revealed post-treatment modifications in both cases;alkali treatments served as a cleanser,eliminating lignin and hemicellulose from the fiber surface,whereas plasma treatments also produce rough surfaces.These results validate the impact of the treatments on the fiber mechanical performance,which opens up possibilities for using Guadua angustifolia fibers as an alternative reinforcement in composite manufacturing.展开更多
In this study,the impacts of egg consumption on mice model of metabolic syndrome(Met S)were comparatively investigated.Mice were divided into five groups(n=8):normal diet group(ND),high-fat diet group(HFD),HFD with wh...In this study,the impacts of egg consumption on mice model of metabolic syndrome(Met S)were comparatively investigated.Mice were divided into five groups(n=8):normal diet group(ND),high-fat diet group(HFD),HFD with whole egg group(WE),HFD with free-yolk egg substitute group(YFES),and HFD with lovastatin group(Lov).Main biochemical indexes and a non-targeted lipidomic analysis were employed to insight the lipid profile changes in serum.It was revealed that WE could significantly improve serum biochemical indexes by reducing body weight,low-density lipoprotein cholesterol(LDL-C)and total cholesterol(TC),while increasing high-density lipoprotein cholesterol.YFES exhibited remarkably better performance in increasing phosphatidylglycerol and phosphatidic acids,while decreasing phosphatidylinositol than WE.A total of 50 differential lipids biomarkers tightly related to glycerophospholipids metabolism were screened out.Carnitine C18:2 and C12:1,SM(d18:0/12:0),and SM(d18:1/14:1)were significantly upregulated in YFES compared to WE.YFES reduced expression of SREBP-1c and Cpt1a,while did not affect the expression of PPAR-α.Sphingomyelin biomarkers were positively related to the TC(|r|>0.6),while PPAR-αwas negatively correlated with triglyceride and LDL-C levels.To sum up,YFES attenuated HFD-induced Met S by improving the serum phospholipids,which account for its modulation of glycerophospholipid metabolism.展开更多
This study explores a symmetric configuration approach in anion exchange membrane(AEM)water electrolysis,focusing on overcoming adaptability challenges in dynamic conditions.Here,a rapid and mild synthesis technique f...This study explores a symmetric configuration approach in anion exchange membrane(AEM)water electrolysis,focusing on overcoming adaptability challenges in dynamic conditions.Here,a rapid and mild synthesis technique for fabricating fibrous membrane-type catalyst electrodes is developed.Our method leverages the contrasting oxidation states between the sulfur-doped NiFe(OH)2 shell and the metallic Ni core,as revealed by electron energy loss spectroscopy.Theoretical evaluations confirm that the S–NiFe(OH)_(2) active sites optimize free energy for alkaline water electrolysis intermediates.This technique bypasses traditional energy-intensive processes,achieving superior bifunctional activity beyond current benchmarks.The symmetric AEM water electrolyzer demonstrates a current density of 2 A cm^(-2) at 1.78 V at 60℃ in 1 M KOH electrolyte and also sustains ampere-scale water electrolysis below 2.0 V for 140 h even in ambient conditions.These results highlight the system's operational flexibility and structural stability,marking a significant advance-ment in AEM water electrolysis technology.展开更多
The chemical activation of various precursors is effective for creating additional closed pores in hard carbons for sodium storage.However,the formation mechanism of closed pores under the influence of pore-forming ag...The chemical activation of various precursors is effective for creating additional closed pores in hard carbons for sodium storage.However,the formation mechanism of closed pores under the influence of pore-forming agents is not well understood.Herein,an effective chemical activation followed by a high-temperature self-healing strategy is employed to generate interconnected closed pores in lignin-derived hard carbon(HCs).By systematic experimental design combined with electron paramagnetic res-onance spectroscopy,it can be found that the content of free radicals in the carbon matrix influences the closure of open pores at high temperatures.Excessively high activation temperature(>700 C)leads to a low free radical concentration,making it difficult to achieve self-healing of open pores at high tempera-tures.By activation at 700°C,a balance between pore making and self-healing is achieved in the final hard carbon.A large number of free radicals triggers rapid growth and aggregation of carbon microcrys-tals,blocking pre-formed open micropores and creating additional interconnected closed pores in as-obtained hard carbons.As a result,the optimized carbon anode(LK-700-1300)delivers a high reversible capacity of 330.8 mA h g^(-1) at 0.03 A g^(-1),which is an increase of 86 mA h g^(-1) compared to the pristine lignin-derived carbon anode(L-700-1300),and exhibits a good rate performance(202.1 mA h g^(-1) at 1 A g^(-1)).This work provides a universal and effective guidance for tuning closed pores of hard carbons from otherprecursors.展开更多
The realization of a stable lithium-metal free(LiMF)sulfur battery based on amorphous carbon anode and lithium sulfide(Li_(2)S)cathode is here reported.In particular,a biomass waste originating full-cell combining a c...The realization of a stable lithium-metal free(LiMF)sulfur battery based on amorphous carbon anode and lithium sulfide(Li_(2)S)cathode is here reported.In particular,a biomass waste originating full-cell combining a carbonized brewer's spent grain(CBSG)biochar anode with a Li_(2)S-graphene composite cathode(Li_(2)S70Gr30)is proposed.This design is particularly attractive for applying a cost-effective,high performance,environment friendly,and safe anode material,as an alternative to standard graphite and metallic lithium in emerging battery technologies.The anodic and cathodic materials are characterized in terms of structure,morphology and composition through X-ray diffraction,scanning and transmission electron microscopy,X-ray photoelectron and Raman spectroscopies.Furthermore,an electrochemical characterization comprising galvanostatic cycling,rate capability and cyclic voltammetry tests were carried out both in half-cell and full-cell configurations.The systematic investigation reveals that unlike graphite,the biochar electrode displays good compatibility with the electrolyte typically employed in sulfur batteries.The CBSG/Li_(2)S70Gr30 full-cell demonstrates an initial charge and discharge capacities of 726 and 537 mAh g^(-1),respectively,at 0.05C with a coulombic efficiency of 74%.Moreover,it discloses a reversible capacity of 330 mAh g^(-1)(0.1 C)after over 300 cycles.Based on these achievements,the CBSG/Li_(2)S70Gr30 battery system can be considered as a promising energy storage solution for electric vehicles(EVs),especially when taking into account its easy scalability to an industrial level.展开更多
Objective Obesity-induced kidney injury contributes to the development of diabetic nephropathy(DN).Here,we identified the functions of ubiquitin-specific peptidase 19(USP19)in HK-2 cells exposed to a combination of hi...Objective Obesity-induced kidney injury contributes to the development of diabetic nephropathy(DN).Here,we identified the functions of ubiquitin-specific peptidase 19(USP19)in HK-2 cells exposed to a combination of high glucose(HG)and free fatty acid(FFA)and determined its association with TGF-beta-activated kinase 1(TAK1).Methods HK-2 cells were exposed to a combination of HG and FFA.USP19 mRNA expression was detected by quantitative RT-PCR(qRT-PCR),and protein analysis was performed by immunoblotting(IB).Cell growth was assessed by Cell Counting Kit-8(CCK-8)viability and 5-ethynyl-2′-deoxyuridine(EdU)proliferation assays.Cell cycle distribution and apoptosis were detected by flow cytometry.The USP19/TAK1 interaction and ubiquitinated TAK1 levels were assayed by coimmunoprecipitation(Co-IP)assays and IB.Results In HG+FFA-challenged HK-2 cells,USP19 was highly expressed.USP19 knockdown attenuated HG+FFA-triggered growth inhibition and apoptosis promotion in HK-2 cells.Moreover,USP19 knockdown alleviated HG+FFA-mediated PTEN-induced putative kinase 1(PINK1)/Parkin pathway inactivation and increased mitochondrial reactive oxygen species(ROS)generation in HK-2 cells.Mechanistically,USP19 stabilized the TAK1 protein through deubiquitination.Importantly,increased TAK1 expression reversed the USP19 knockdown-mediated phenotypic changes and PINK1/Parkin pathway activation in HG+FFA-challenged HK-2 cells.Conclusion The findings revealed that USP19 plays a crucial role in promoting HK-2 cell dysfunction induced by combined stimulation with HG and FFAs by stabilizing TAK1,providing a potential therapeutic strategy for combating DN.展开更多
In this paper, a novel efficient energy absorber with free inversion of a metal foam-filled circular tube(MFFCT) is designed, and the axial compressive behavior of the MFFCT under free inversion is studied analyticall...In this paper, a novel efficient energy absorber with free inversion of a metal foam-filled circular tube(MFFCT) is designed, and the axial compressive behavior of the MFFCT under free inversion is studied analytically and numerically. The theoretical analysis reveals that the energy is mainly dissipated through the radial bending of the metal circular tube, the circumferential expansion of the metal circular tube, and the metal filled-foam compression. The principle of energy conservation is used to derive the theoretical formula for the minimum compressive force of the MFFCT over free inversion under axial loading. Furthermore, the free inversion deformation characteristics of the MFFCT are analyzed numerically. The theoretical steady values are found to be in good agreement with the results of the finite element(FE) analysis. The effects of the average diameter of the metal tube, the wall thickness of the metal tube, and the filled-foam strength on the free inversion deformation of the MFFCT are considered. It is observed that in the steady deformation stage, the load-carrying and energy-absorbing capacities of the MFFCT increase with the increase in the average diameter of the metal tube, the wall thickness of the metal tube, or the filled-foam strength. The specific energy absorption(SEA) of free inversion of the MFFCT is significantly higher than that of the metal tube alone.展开更多
For reaction-diffusion equations in irregular domains with moving boundaries,the numerical stability constraints from the reaction and diffusion terms often require very restricted time step sizes,while complex geomet...For reaction-diffusion equations in irregular domains with moving boundaries,the numerical stability constraints from the reaction and diffusion terms often require very restricted time step sizes,while complex geometries may lead to difficulties in the accuracy when discretizing the high-order derivatives on grid points near the boundary.It is very challenging to design numerical methods that can efficiently and accurately handle both difficulties.Applying an implicit scheme may be able to remove the stability constraints on the time step,however,it usually requires solving a large global system of nonlinear equations for each time step,and the computational cost could be significant.Integration factor(IF)or exponential time differencing(ETD)methods are one of the popular methods for temporal partial differential equations(PDEs)among many other methods.In our paper,we couple ETD methods with an embedded boundary method to solve a system of reaction-diffusion equations with complex geometries.In particular,we rewrite all ETD schemes into a linear combination of specificФ-functions and apply one state-of-the-art algorithm to compute the matrix-vector multiplications,which offers significant computational advantages with adaptive Krylov subspaces.In addition,we extend this method by incorporating the level set method to solve the free boundary problem.The accuracy,stability,and efficiency of the developed method are demonstrated by numerical examples.展开更多
基金supported by the National Key Research and Development Program of China(2020YFB1713500)the Chinese 02 Special Fund(2017ZX02408003)+1 种基金Open Fund of State Key Laboratory of Advanced Refractories(SKLAR202210)the Foundation of Department of Science and Technology of Henan Province(212102210219).
文摘Alkali metals(Li,Na,and K)are promising candidates for high-performance rechargeable alkali metal battery anodes due to their high theoretical specific capacity and low electrochemical potential.However,the actual application of alkali metal anodes is impeded by the challenges of alkali metals,including their high chemical reactivity,uncontrolled dendrite growth,unstable solid electrolyte interphase,and infinite volume expansion during cycling processes.Introducing carbon nanotube-based nanomaterials in alkali metal anodesis an effective solution to these issues.These nanomaterials have attracted widespread attention owing to their unique properties,such as their high specific surface area,superior electronic conductivity,and excellent mechanical stability.Considering the rapidly growing research enthusiasm for this topic in the last several years,we review recent progress on the application of carbon nanotube-based nanomaterials in stable and dendrite-free alkali metal anodes.The merits and issues of alkali metal anodes,as well as their stabilizing strategies are summarized.Furthermore,the relationships among methods of synthesis,nano-or microstructures,and electrochemical properties of carbon nanotube-based alkali metal anodes are systematically discussed.In addition,advanced characterization technologies on the reaction mechanism of carbon nanotube-based nanomaterials in alkali metal anodes are also reviewed.Finally,the challenges and prospects for future study and applications of carbon nanotube-based AMAs in high-performance alkali metal batteries are discussed.
基金supported by the State Key Laboratory of Natural Gas Hydrate(No.2022-KFJJ-SHW)the National Natural Science Foundation of China(No.42376058)+2 种基金the International Science&Technology Cooperation Program of China(No.2023YFE0119900)the Hainan Province Key Research and Development Project(No.ZDYF2024GXJS002)the Research Start-Up Funds of Zhufeng Scholars Program.
文摘Gas hydrate drilling expeditions in the Pearl River Mouth Basin,South China Sea,have identified concentrated gas hydrates with variable thickness.Moreover,free gas and the coexistence of gas hydrate and free gas have been confirmed by logging,coring,and production tests in the foraminifera-rich silty sediments with complex bottom-simulating reflectors(BSRs).The broad-band processing is conducted on conventional three-dimensional(3D)seismic data to improve the image and detection accuracy of gas hydratebearing layers and delineate the saturation and thickness of gas hydrate-and free gas-bearing sediments.Several geophysical attributes extracted along the base of the gas hydrate stability zone are used to demonstrate the variable distribution and the controlling factors for the differential enrichment of gas hydrate.The inverted gas hydrate saturation at the production zone is over 40% with a thickness of 90 m,showing the interbedded distribution with different boundaries between gas hydrate-and free gas-bearing layers.However,the gas hydrate saturation value at the adjacent canyon is 70%,with 30-m-thick patches and linear features.The lithological and fault controls on gas hydrate and free gas distributions are demonstrated by tracing each gas hydrate-bearing layer.Moreover,the BSR depths based on broad-band reprocessed 3D seismic data not only exhibit variations due to small-scale topographic changes caused by seafloor sedimentation and erosion but also show the upward shift of BSR and the blocky distribution of the coexistence of gas hydrate and free gas in the Pearl River Mouth Basin.
基金supported by the Key Project of the NSFC(12131010)the NSFC(11771155,12271032)+1 种基金the NSF of Guangdong Province(2021A1515010249,2021A1515010303)supported by the NSFC(11971179,12371205)。
文摘This paper is concerned with the Navier-Stokes/Allen-Cahn system,which is used to model the dynamics of immiscible two-phase flows.We consider a 1D free boundary problem and assume that the viscosity coefficient depends on the density in the form ofη(ρ)=ρ^(α).The existence of unique global H^(2m)-solutions(m∈N)to the free boundary problem is proven for when 0<α<1/4.Furthermore,we obtain the global C^(∞)-solutions if the initial data is smooth.
基金The authors are grateful for the financial support from National Natural Science Foundation of China(32001728).
文摘Free amino acid(FAA)is the important component of vinegar that infl uences quality perception and consumer acceptance.FAA is one of the major metabolites produced by microorganisms;however,the microbial metabolic network on FAA biosynthesis remains unclear.Through metagenomic analysis,this work aimed to elucidate the roles of microbes in FAA biosynthesis during Monascus rice vinegar fermentation.Taxonomic profiles from functional analyses showed 14 dominant genera with high contributions to the metabolism pathways.The metabolic network for FAA biosynthesis was then constructed,and the microbial distribution in different metabolic pathways was illuminated.The results revealed that 5 functional genera were closely involved in FAA biosynthesis.This study illuminated the metabolic roles of microorganisms in FAA biosynthesis and provided crucial insights into the functional attributes of microbiota in vinegar fermentation.
基金supported by the Excellent Youth Foundation of Jilin Province,China(Grant No.20230101361JC)the National Natural Science Foundation of China(Grant No.U21A2037)+1 种基金the CAS Interdisciplinary Innovation Team Project(Grant No.JCTD-2020-14)the Youth Innovation Promotion Association,Chinese Academy of Sciences(CAS)(Grant No.Y2021068)。
文摘Nitrogen(N),phosphorus(P)and carbon(C)are essential nutrients for rice growth and development,but the response of nutrient absorption by rice plants to different types of nitrogen fertilizer(N-fertilizer)under saline-alkali conditions is unclear.This study conducted a 147-day field-scale experiment to evaluate rice biomass and nutrient absorption capacity with five N-fertilizer applications.The results showed that the biomass.
基金funded by the Engineering and Physical Sciences Research Council(EPSRC),UK(EP/S019650/1)funded by EPSRC via an Early Career Fellowship grant(EP/R001642/1)+2 种基金the Transforming Foundation Industries:Network+Towards Value by Innovation(EP/V026402/1)funded by the National Nature Science Foundation of China(U2001225)Fundamental Research Funds for the Central Universities(22120230174 at Tongji University),and Geopoly Fundamental Genomic Research project.
文摘1.Introduction and context Enormous emphasis is currently being paid to the decarbonization of the global built environment as a leading priority for the engineering community and related industrial sectors[1].One of the main contributors to the overall emissions footprint of the built environment-and thus a cornerstone of efforts to achieve decarbonization-is the emissions profile of construction materials during their production and utilization.The cement and concrete sector is the largest-volume contributor to the emissions incurred in meeting the world’s construction material needs and is therefore targeted in the discussion of the deep,rapid decarbonization that must be achieved in order to minimize irreversible damage to the Earth and its ecosystems.
基金jointly supported by the Guangdong Major Project of Basic and Applied Basic Research (2023B0303000002)National Natural Science Foundation of China (22178126,22325802,U22A20417,22208110)+3 种基金Guangdong Basic and Applied Basic Research Foundation (2023B1515120005)Science and Technology Program of Guangzhou (2023B03J1281,2023A04J1357)China Postdoctoral Science Foundation (2023T160223)the State Key Laboratory of Pulp and Paper Engineering (2023ZD03)。
文摘Viologens known as a kind of promising negolyte materials for aqueous organic redox flow batteries,face a critical stability challenge due to the S_N2 nucleophilic attack by hydroxide ions(OH-)during the battery cycling.In this work,a N-cyclic quaternary ammonium-grafted viologen molecule,viz.1,1'-bis(4,4'-dime thylpiperidiniumyl)-4,4'-bipyridinium tetrachloride((DBPPy)Cl_(4)),is developed by the molecular engineering strategy.The obtained(DBPPy)Cl_(4) molecule shows a decent solubility of 1.84 M and a redox potential of-0.52 V vs.Ag/AgCl,Experimental and theoretical results reveal that the grafted N-cyclic quaternary ammonium groups act as the steric hindrance to prevent nucleophilic attack by OH~-,increasing the alkali resistance of the electroactive molecule.The symmetrical battery with 0.50 M(DBPPy)Cl4shows negligible decay during the 13-day cycling test.As demonstration,the flow battery utilizing 1.0 M(DBPPy)Cl_(4) as the negolyte and 1-(1-oxyl-2,2',6,6'-tetramethylpiperidin-4-yl)-1'-(3-(trimethylammonio)propyl)-4,4'-bipyridinium trichloride as the posolyte exhibits a high capacity retention rate of 99.99%per cycle at 60 mA cm^(-2).
基金This work was supported by the National Key R&D Program of China(Nos.2022YFB3504100 and 2022YFB3504102)Natural National Science Foundation of China(No.22276133)+1 种基金Natural National Science Foundation of China(No.U20A20132)Natural National Science Foundation of China(No.52106180).
文摘The existence of alkali metals in fl ue gases originating from stationary sources can result in catalyst deactivation in the low-temperature selective catalytic reduction(SCR)of nitrogen oxides(NO_(x)).It is widely accepted that alkali metal poisoning causes damage to the acidic sites of catalysts.Therefore,in this study,a series of CoMn catalysts doped with heteropolyacids(HPAs)were prepared using the coprecipitation method.Among these,CoMnHPMo exhibited superior catalytic performance for SCR and over 95%NO_(x) conversion at 150-300.Moreover,it exhibited excellent catalytic activity and stability after alkali poisoning,demonstrating outstanding alkali metal resistance.The characterization indicated that HPMo increased the specifi c surface area of the catalyst,which provided abundant adsorption sites for NO_(x) and NH_(3).Comparing catalysts before and after poisoning,CoMnHPMo enhanced its alkali metal resistance by sacrifi cing Brønsted acid sites to protect its Lewis acid sites.In situ DRIFTS was used to study the reaction pathways of the catalysts.The results showed that CoMnHPMo maintained high NH_(3) adsorption capacity after K poisoning and then reacted rapidly with NO intermediates to ensure that the active sites were not covered.Consequently,SCR performance was ensured even after alkali metal poisoning.In sum-mary,this research proposed a simple method for the design of an alkali-resistant NH_(3)-SCR catalyst with high activity at low temperatures.
基金Funded by the National Key Research and Development Program of China (No.2019YFC1906202)the Guangxi Key Research and Development Plan (Nos.Guike AA18242007-3, Guike AB19259008, and Guike AB20297014)。
文摘Internal curing agents (ICA) based on super absorbent polymer have poor alkali tolerance and reduce the early strength of concrete.An alkali tolerate internal curing agent (CAA-ICA) was designed and prepared by using sodium carboxymethyl starch (CMS) with high hydrophilicity,acrylic acid (AA) containing anionic carboxylic group and acrylamide (AM) containing non-ionic amide group as the main raw materials.The results show that the ratio of CAA-ICA alkali absorption solution is higher than that existing ICA,which solves the low water absorption ratio of the ICA in alkali environment.The water absorption ratio of CAA-ICA in saturated Ca(OH)_(2) solution is 95.8 g·g^(-1),and the alkali tolerance coefficient is 3.4.The application of CAA-ICA in cement-based materials can increase the internal relative humidity and miniaturize the pore structure.The compressive strength of mortar increases up to 12.95%at 28 d,which provids a solution to overcome the reduction of the early strength.
基金supported by the National Natural Science Foundation of China(52162030)the Yunnan Major Scientific and Technological Projects(202202AG050003)+4 种基金the Key Research and Development Program of Yunnan Province(202103AA080019)the Scientific Research Foundation of Kunming University of Science and Technology(20220122)the Graduate Student Top Innovative Talent Program of Kunming University of Science and Technology(CA23107M139A)the Analysis and Testing Foundation of Kunming University of Science and Technology(2023T20220122)the Shenzhen Science and Technology Program(KCXST20221021111201003)。
文摘High-energy density lithium-ion batteries(LIBs)with layered high-nickel oxide cathodes(LiNi_(x)Co_(y)Mn_(1-x-y)O_(2),x≥0.8)show great promise in consumer electronics and vehicular applications.However,LiNi_(x)Co_(y)Mn_(1-x-y)O_(2)faces challenges related to capacity decay caused by residual alkalis owing to high sensitivity to air.To address this issue,we propose a hazardous substances upcycling method that fundamentally mitigates alkali content and concurrently induces the emergence of an anti-air-sensitive layer on the cathode surface.Through the neutralization of polyacrylic acid(PAA)with residual alkalis and then coupling it with 3-aminopropyl triethoxysilane(KH550),a stable and ion-conductive cross-linked polymer layer is in situ integrated into the LiNi_(0.89)Co_(0.06)Mn_(0.05)O_(2)(NCM)cathode.Our characterization and measurements demonstrate its effectiveness.The NCM material exhibits impressive cycling performance,retaining 88.4%of its capacity after 200 cycles at 5 C and achieving an extraordinary specific capacity of 170.0 mA h g^(-1) at 10 C.Importantly,this layer on the NCM efficiently suppresses unfavorable phase transitions,severe electrolyte degradation,and CO_(2)gas evolution,while maintaining commendable resistance to air exposure.This surface modification strategy shows widespread potential for creating air-stable LiNi_(x)Co_(y)Mn_(1-x-y)O_(2)cathodes,thereby advancing high-performance LIBs.
基金supported in part by the National Natural Science Foundation of China(12101088)the Natural Science Foundation of Sichuan Province(2022NSFSC1858)。
文摘This paper is devoted to the study of the shape of the free boundary for a threedimensional axisymmetric incompressible impinging jet.To be more precise,we will show that the free boundary is convex to the fluid,provided that the uneven ground is concave to the fluid.
文摘This study focuses on treating Guadua angustifolia bamboo fibers to enhance their properties for reinforcement applications in composite materials.Chemical(alkali)and physical(dry etching plasma)treatments were used separately to augment compatibility of Guadua angustifolia fibers with various composite matrices.The influence of these treatments on the fibers’performance,chemical composition,and surface morphology were analyzed.Statistical analysis indicated that alkali treatments reduced the tensile modulus of elasticity and strength of fibers by up to 40%and 20%,respectively,whereas plasma treatments maintain the fibers’mechanical performance.FTIR spectroscopy revealed significant alterations in chemical composition due to alkali treatments,while plasma-treated fibers showed minimal changes.Surface examination through Scanning Electron Microscopy(SEM)revealed post-treatment modifications in both cases;alkali treatments served as a cleanser,eliminating lignin and hemicellulose from the fiber surface,whereas plasma treatments also produce rough surfaces.These results validate the impact of the treatments on the fiber mechanical performance,which opens up possibilities for using Guadua angustifolia fibers as an alternative reinforcement in composite manufacturing.
基金supported by the Applied Basic Research of Shanxi Province(201901D211381)the Innovation-driven Development Capacity Enhancement Fund of Shanxi Province(SXYBKY2019041)+2 种基金National Key Research and Development Program(2021YFD1600604-03)Shanxi Scholarship Council of China(2021-068)Shanxi Agricultural University High-Level Talent Project(2021XG013)。
文摘In this study,the impacts of egg consumption on mice model of metabolic syndrome(Met S)were comparatively investigated.Mice were divided into five groups(n=8):normal diet group(ND),high-fat diet group(HFD),HFD with whole egg group(WE),HFD with free-yolk egg substitute group(YFES),and HFD with lovastatin group(Lov).Main biochemical indexes and a non-targeted lipidomic analysis were employed to insight the lipid profile changes in serum.It was revealed that WE could significantly improve serum biochemical indexes by reducing body weight,low-density lipoprotein cholesterol(LDL-C)and total cholesterol(TC),while increasing high-density lipoprotein cholesterol.YFES exhibited remarkably better performance in increasing phosphatidylglycerol and phosphatidic acids,while decreasing phosphatidylinositol than WE.A total of 50 differential lipids biomarkers tightly related to glycerophospholipids metabolism were screened out.Carnitine C18:2 and C12:1,SM(d18:0/12:0),and SM(d18:1/14:1)were significantly upregulated in YFES compared to WE.YFES reduced expression of SREBP-1c and Cpt1a,while did not affect the expression of PPAR-α.Sphingomyelin biomarkers were positively related to the TC(|r|>0.6),while PPAR-αwas negatively correlated with triglyceride and LDL-C levels.To sum up,YFES attenuated HFD-induced Met S by improving the serum phospholipids,which account for its modulation of glycerophospholipid metabolism.
基金This research was supported by the“Regional Innovation Strategy(RIS)”through the National Research Foundation of Korea(NRF)funded by the Ministry of Education(MOE)(2021RIS-002)This work was supported by an NRF grant funded by the Ministry of Science,ICT,and Future Planning(No.NRF-2018R1C1B6005009,NRF-2021R1C1C1012676,and 2009-0082580).
文摘This study explores a symmetric configuration approach in anion exchange membrane(AEM)water electrolysis,focusing on overcoming adaptability challenges in dynamic conditions.Here,a rapid and mild synthesis technique for fabricating fibrous membrane-type catalyst electrodes is developed.Our method leverages the contrasting oxidation states between the sulfur-doped NiFe(OH)2 shell and the metallic Ni core,as revealed by electron energy loss spectroscopy.Theoretical evaluations confirm that the S–NiFe(OH)_(2) active sites optimize free energy for alkaline water electrolysis intermediates.This technique bypasses traditional energy-intensive processes,achieving superior bifunctional activity beyond current benchmarks.The symmetric AEM water electrolyzer demonstrates a current density of 2 A cm^(-2) at 1.78 V at 60℃ in 1 M KOH electrolyte and also sustains ampere-scale water electrolysis below 2.0 V for 140 h even in ambient conditions.These results highlight the system's operational flexibility and structural stability,marking a significant advance-ment in AEM water electrolysis technology.
基金supported by the National Natural Science Foundation of China (22379157,22179139)the Key Research and Development (R&D) Projects of Shanxi Province(202102040201003)+1 种基金the Research Program of Shanxi Province(202203021211203)the ICC CAS (SCJC-XCL-2023-10 and SCJC-XCL-2023-13)
文摘The chemical activation of various precursors is effective for creating additional closed pores in hard carbons for sodium storage.However,the formation mechanism of closed pores under the influence of pore-forming agents is not well understood.Herein,an effective chemical activation followed by a high-temperature self-healing strategy is employed to generate interconnected closed pores in lignin-derived hard carbon(HCs).By systematic experimental design combined with electron paramagnetic res-onance spectroscopy,it can be found that the content of free radicals in the carbon matrix influences the closure of open pores at high temperatures.Excessively high activation temperature(>700 C)leads to a low free radical concentration,making it difficult to achieve self-healing of open pores at high tempera-tures.By activation at 700°C,a balance between pore making and self-healing is achieved in the final hard carbon.A large number of free radicals triggers rapid growth and aggregation of carbon microcrys-tals,blocking pre-formed open micropores and creating additional interconnected closed pores in as-obtained hard carbons.As a result,the optimized carbon anode(LK-700-1300)delivers a high reversible capacity of 330.8 mA h g^(-1) at 0.03 A g^(-1),which is an increase of 86 mA h g^(-1) compared to the pristine lignin-derived carbon anode(L-700-1300),and exhibits a good rate performance(202.1 mA h g^(-1) at 1 A g^(-1)).This work provides a universal and effective guidance for tuning closed pores of hard carbons from otherprecursors.
基金the Natural Science Foundation of China,grant no.32071317
文摘The realization of a stable lithium-metal free(LiMF)sulfur battery based on amorphous carbon anode and lithium sulfide(Li_(2)S)cathode is here reported.In particular,a biomass waste originating full-cell combining a carbonized brewer's spent grain(CBSG)biochar anode with a Li_(2)S-graphene composite cathode(Li_(2)S70Gr30)is proposed.This design is particularly attractive for applying a cost-effective,high performance,environment friendly,and safe anode material,as an alternative to standard graphite and metallic lithium in emerging battery technologies.The anodic and cathodic materials are characterized in terms of structure,morphology and composition through X-ray diffraction,scanning and transmission electron microscopy,X-ray photoelectron and Raman spectroscopies.Furthermore,an electrochemical characterization comprising galvanostatic cycling,rate capability and cyclic voltammetry tests were carried out both in half-cell and full-cell configurations.The systematic investigation reveals that unlike graphite,the biochar electrode displays good compatibility with the electrolyte typically employed in sulfur batteries.The CBSG/Li_(2)S70Gr30 full-cell demonstrates an initial charge and discharge capacities of 726 and 537 mAh g^(-1),respectively,at 0.05C with a coulombic efficiency of 74%.Moreover,it discloses a reversible capacity of 330 mAh g^(-1)(0.1 C)after over 300 cycles.Based on these achievements,the CBSG/Li_(2)S70Gr30 battery system can be considered as a promising energy storage solution for electric vehicles(EVs),especially when taking into account its easy scalability to an industrial level.
基金supported by Natural Science Foundation of Shaanxi Province(No.2023-JC-YB-743 and No.2021JQ-905).
文摘Objective Obesity-induced kidney injury contributes to the development of diabetic nephropathy(DN).Here,we identified the functions of ubiquitin-specific peptidase 19(USP19)in HK-2 cells exposed to a combination of high glucose(HG)and free fatty acid(FFA)and determined its association with TGF-beta-activated kinase 1(TAK1).Methods HK-2 cells were exposed to a combination of HG and FFA.USP19 mRNA expression was detected by quantitative RT-PCR(qRT-PCR),and protein analysis was performed by immunoblotting(IB).Cell growth was assessed by Cell Counting Kit-8(CCK-8)viability and 5-ethynyl-2′-deoxyuridine(EdU)proliferation assays.Cell cycle distribution and apoptosis were detected by flow cytometry.The USP19/TAK1 interaction and ubiquitinated TAK1 levels were assayed by coimmunoprecipitation(Co-IP)assays and IB.Results In HG+FFA-challenged HK-2 cells,USP19 was highly expressed.USP19 knockdown attenuated HG+FFA-triggered growth inhibition and apoptosis promotion in HK-2 cells.Moreover,USP19 knockdown alleviated HG+FFA-mediated PTEN-induced putative kinase 1(PINK1)/Parkin pathway inactivation and increased mitochondrial reactive oxygen species(ROS)generation in HK-2 cells.Mechanistically,USP19 stabilized the TAK1 protein through deubiquitination.Importantly,increased TAK1 expression reversed the USP19 knockdown-mediated phenotypic changes and PINK1/Parkin pathway activation in HG+FFA-challenged HK-2 cells.Conclusion The findings revealed that USP19 plays a crucial role in promoting HK-2 cell dysfunction induced by combined stimulation with HG and FFAs by stabilizing TAK1,providing a potential therapeutic strategy for combating DN.
基金Project supported by the National Natural Science Foundation of China (Nos. 12272290 and11872291)the State Key Laboratory of Automotive Safety and Energy of China (No. KFY2202)。
文摘In this paper, a novel efficient energy absorber with free inversion of a metal foam-filled circular tube(MFFCT) is designed, and the axial compressive behavior of the MFFCT under free inversion is studied analytically and numerically. The theoretical analysis reveals that the energy is mainly dissipated through the radial bending of the metal circular tube, the circumferential expansion of the metal circular tube, and the metal filled-foam compression. The principle of energy conservation is used to derive the theoretical formula for the minimum compressive force of the MFFCT over free inversion under axial loading. Furthermore, the free inversion deformation characteristics of the MFFCT are analyzed numerically. The theoretical steady values are found to be in good agreement with the results of the finite element(FE) analysis. The effects of the average diameter of the metal tube, the wall thickness of the metal tube, and the filled-foam strength on the free inversion deformation of the MFFCT are considered. It is observed that in the steady deformation stage, the load-carrying and energy-absorbing capacities of the MFFCT increase with the increase in the average diameter of the metal tube, the wall thickness of the metal tube, or the filled-foam strength. The specific energy absorption(SEA) of free inversion of the MFFCT is significantly higher than that of the metal tube alone.
文摘For reaction-diffusion equations in irregular domains with moving boundaries,the numerical stability constraints from the reaction and diffusion terms often require very restricted time step sizes,while complex geometries may lead to difficulties in the accuracy when discretizing the high-order derivatives on grid points near the boundary.It is very challenging to design numerical methods that can efficiently and accurately handle both difficulties.Applying an implicit scheme may be able to remove the stability constraints on the time step,however,it usually requires solving a large global system of nonlinear equations for each time step,and the computational cost could be significant.Integration factor(IF)or exponential time differencing(ETD)methods are one of the popular methods for temporal partial differential equations(PDEs)among many other methods.In our paper,we couple ETD methods with an embedded boundary method to solve a system of reaction-diffusion equations with complex geometries.In particular,we rewrite all ETD schemes into a linear combination of specificФ-functions and apply one state-of-the-art algorithm to compute the matrix-vector multiplications,which offers significant computational advantages with adaptive Krylov subspaces.In addition,we extend this method by incorporating the level set method to solve the free boundary problem.The accuracy,stability,and efficiency of the developed method are demonstrated by numerical examples.