NASICON-type vanadium fluorophosphate is a promising cathode for sodium-ion batteries.Yet,the thermally-driven loss of undercoordinated dangling fluorine anions weakens its structural stability,which triggers severe f...NASICON-type vanadium fluorophosphate is a promising cathode for sodium-ion batteries.Yet,the thermally-driven loss of undercoordinated dangling fluorine anions weakens its structural stability,which triggers severe framework distortion from interconnected double-octahedral to isolated local octahedral units,as well as a degeneracy of t_(2g) electronic configuration of vanadium(V)3d orbit.In this work,it is clarified that such a degenerate state undergoes spontaneous lattice evolution to reduce the system energy,which causes a low crystalline symmetry and a parasitic V^(4+)/V^(3+)redox reaction in the low-voltage region.Herein,an anion-coordination regulation strategy is developed to suppress this degeneration by anchoring fluorine anions in the double-octahedral[V_(2)O_(8)F_(3)]framework.Density functional theory calculations and in-situ techniques track the F-anion-driven structural evolution and charge compensation mechanisms,revealing that this strategy mitigates detrimental phase segregation during the initial desodiation stage and enhances the Na^(+)diffusion kinetic rate over a factor of 100.Concurrently,this strategy releases the V^(4+)/V^(3+)redox kinetics by eliminating the parasitic low-voltage plateau.The full-cell assembled with the optimized fluorophosphate cathode delivers an increase of 50%in discharge capacity and stable two-voltage-plateau behavior,enabled by its double-octahedral[V_(2)O_(8)F_(3)]polyanionic structure that facilitates unimpeded three-dimensional(3D)Na^(+)transport.By correlating anion-coordination stability with orbital-level charge compensation,this work establishes a universal paradigm for highperformance polyanionic cathodes,positioning it as a competitive candidate for battery applications.展开更多
Designing transition metal nickel-cobalt-based battery-type electrode materials driven by anions is crucial for achieving rapid OH-ion transport under electrochemical activation conditions,thereby improving capacitanc...Designing transition metal nickel-cobalt-based battery-type electrode materials driven by anions is crucial for achieving rapid OH-ion transport under electrochemical activation conditions,thereby improving capacitance performance.Herein,borate anions are selected through theoretical calculations,and twodimensional(2D)defect-rich amorphous nickel-cobalt-based borate is synthesized via a facile chemical reduction method.Under potentiostatic modification,activated products(NCB-G-E)are obtained.In situ Raman spectra reveal that electron-deficient borate extracts electrons from metal centers,facilitating the oxidation state transition of Ni and Co.Theoretical calculations show that in situ adsorbed borate regulates the d-band centers of metal sites,enhancing OH^(-)intermediate adsorption.Meanwhile,borate anion adsorption accelerates the deprotonation and activation processes.Electrochemical tests demonstrate that NCB-G-E displays superior capacitance performance,with a high quality specific capacity of383.3 mA h g^(-1)and 65% retention rate at 30 A g^(-1),surpassing most nickel-cobalt-based electrodes.The assembled asymmetric supercapacitor presents an impressive energy density of 68.2 Wh kg^(-1)and good cycling stability.This work highlights the role of electron-deficient borate in tuning metal band structure and promoting oxidation state transition through synergistic defect advantages,offering new prospects for advanced battery-type energy storage materials.展开更多
In order to find the optimal anions and cations for designing energetic salts with excellent detonation properties,the properties of 140 salts formed from the anions(A–G)of 3,3′-dinitroamino-4,4′-azoxyfurazan(DAAF)...In order to find the optimal anions and cations for designing energetic salts with excellent detonation properties,the properties of 140 salts formed from the anions(A–G)of 3,3′-dinitroamino-4,4′-azoxyfurazan(DAAF)derivatives substituted with the—NH_(2),—N_(3) or—NO_(2) group and the cations(1–20)of guanidine,triazole,or tetrazole derivatives were investigated by means of density-functional theory.The predicted densities,heats of formation,detonation velocities(D),and detonation pressures(P)of 140 salts were 11.72 to 2.06 g·cm ^(−3),570.2 to 2333.4 kJ·mol^(−1),8.29 to 10.02 km·s^(−1) and 30.16 to 47.57 GPa,respectively.Most of the salts had better detonation properties than the widely used hexahydro-1,3,5-trinitro-1,3,5-triazine(RDX).Salts containing—NO_(2) group anions(C and F)have better detonation properties(D is 8.88 to 10.02 km·s^(−1) and P is 35.75 to 47.75 GPa)than other salts.Salts containing the cations NH_(4)^(+)(1),NH_(3)OH^(+)(2)and CH_(2)N_(4)NO_(2)^(+)(20)had good detonation properties(D is 9.38 to 10.02 km·s^(−1) and P is 40.72 to 47.75 GPa).Depending on the detonation properties,anions(C and F)and cations(1,2 and 20)are the recommended ions for the generation of energetic salts.展开更多
Anion modification has been considered as a strategy to improve water splitting efficiency upon oxygen evolution reaction(OER).However,constructing a novel catalysis system with high catalytic activity and precise str...Anion modification has been considered as a strategy to improve water splitting efficiency upon oxygen evolution reaction(OER).However,constructing a novel catalysis system with high catalytic activity and precise structures is still a huge challenge due to the tedious procedure of precursor synthesis and anion selection.Here,a bimetallic(FeNi)nanowire self-assembled superstructure was synthesized using the Hoffmann rearrangement method,and then functionalized with four anions(P,Se,S,and O).Notably,the Fe_(3)Se_(4)/Ni_(3)Se_(4) catalyst shows a high conductivity,enhances the adsorption of intermediate products,accelerates the rate-determining step,and consequently results to improved electrocatalytic performance.Using the Fe_(3)Se_(4)/Ni_(3)Se_(4) catalyst exhibits enhanced performance with overpotential of 316mV at 10 mA/cm^(2),in stark contrast to Fe_(2) P/Ni_(2)P(357mV),Fe_(7)S_(8)/NiS(379 mV),and Fe_(3)O_(4)/NiO(464 mV).Moreover,the formation mechanism of superstructure and the relationship between electronegativities and electrocatalytic properties,are elucidated.Accordingly,this work provides an efficient approach to Hoffmann-type coordination polymer catalyst for oxygen evolution towards a near future.展开更多
A plasma injection ion source has been de-veloped for the photoelectron velocity imag-ing studies of metal-containing anions.The source employs a pulse discharge nozzle for generating a plasma beam that perpendicu-lar...A plasma injection ion source has been de-veloped for the photoelectron velocity imag-ing studies of metal-containing anions.The source employs a pulse discharge nozzle for generating a plasma beam that perpendicu-larly crosses the master supersonic jet beam from a home-made pulsed piezo valve.The discharge nozzle is designed for high voltage gas discharge with efficient metal sputtering of the cathode,and thus plays a role in met-al atom and ion source.Supersonically jet-cooled anions can be produced in the master gas jet via reactions of the plasma products.The source is integrated into a photoelectron ve-locity imaging spectrometer.Test mass spectrometry experiments show that the ion source can efficiently produce transition metal containing anions,such as FeO_(m)^(-),CuO_(m)^(-),CuC_(n)^(-),CuC_(n)O_(m)^(-).The photoelectron imaging results by photodetachment of O-show that the pho-toelectron energy resolution of the whole instrument isΔE/E≈2.3%,and the results of FeO^(-)indicate that internal temperatures of anions from the source could be efficiently cooled down.展开更多
Bauxite residue is a highly alkaline waste containing soluble alkaline anions,which can cause environmental concerns.The optimal leaching conditions,distribution of alkaline anions,types of pivotal alkaline anions and...Bauxite residue is a highly alkaline waste containing soluble alkaline anions,which can cause environmental concerns.The optimal leaching conditions,distribution of alkaline anions,types of pivotal alkaline anions and their dissolution behaviors were investigated based on the combination of single factors-orthogonal experiments and leaching stage experiment.Using a two-stage leaching,86%of the soluble alkaline anions(CO3^2-,HCO4^-,Al(OH)4^-,OH^-)were leached with a L/S ratio of 2 mL/g,at 30℃,over 23 h.During the first stage of leaching,approximately 88%of alkaline anions were leached from the dissolution of free alkali(Na OH,carbonate,bicarbonate,NaAl(OH)4)with the rest originating from the dissolution of alkaline minerals(calcite,cancrinite and hydrogarnet).Supernatant alkalinity was 69.78 mmol/L with CO3^2-accounting for 75%.Furthermore,carbonate leaching was controlled by solid film diffusion using the Stumm Model with an apparent activation energy of 10.24 kJ/mol.展开更多
A column leaching experiment was used to investigate the efficacy of amendments on their ability to remove alkaline anions and metal ions from bauxite residue leachates.Treatments included,simulated acid rain (AR),pho...A column leaching experiment was used to investigate the efficacy of amendments on their ability to remove alkaline anions and metal ions from bauxite residue leachates.Treatments included,simulated acid rain (AR),phosphogypsum + vermicompost (PVC),phosphogypsum + vermicompost + simulated acid rain (PVA),and biosolids + microorganisms (BSM) together with controls (CK).Results indicated that amendment could effectively reduce the leachate pH and EC values,neutralize OH-,CO32-,HCO3-,and water soluble alkali,and suppress arsenic (As) content.Correlation analysis revealed significant linear correlations with pH and concentrations of OH-,CO32-,HCO3-,water-soluble alkali,and metal ions.BSM treatment showed optimum results with neutralizing anions (OH-,CO32-,and HCO3-),water soluble alkali,and removal of metal ions (Al,As,B,Mo,V,and Na),which was attributed to neutralization from the generation of small molecular organic acids and organic matter during microbial metabolism.BSM treatment reduced alkaline anions and metal ions based on neutralization reactions in bauxite residue leachate,which reduced the potential pollution effects from leachates on the soil surrounding bauxite residue disposal areas.展开更多
Aluminum （AI） toxicity and phosphorous （P） deficiency are two major limiting factors for plant growth on acidic soils. Thus, the physiological mechanisms for AJ tolerance and P acquisition have been intensively st...Aluminum （AI） toxicity and phosphorous （P） deficiency are two major limiting factors for plant growth on acidic soils. Thus, the physiological mechanisms for AJ tolerance and P acquisition have been intensively studied. A commonly observed trait is that plants have developed the ability to utilize organic acid anions （OAs; mainly malate, citrate and oxalate） to combat AI toxicity and P deficiency. OAs secreted by roots into the rhizosphere can externally chelate Al^3＋ and mobilize phosphate （Pi）, while OAs synthesized in the cell can internally sequester Al^3＋ into the vacuole and release free Pi for metabolism. Molecular mechanisms involved in OA synthesis and transport have been described in detail. Ensuing genetic improvement for AI tolerance and P efficiency through increased OA exudation and/or synthesis in crops has been achieved by transgenic and marker-assisted breeding. This review mainly elucidates the crucial roles of OAs in plant Al tolerance and P efficiency through summarizing associated physiological mechanisms, molecular traits and genetic manipulation of crops.展开更多
Micro-emulsion usually consists of water, oil, surfactants and co-surfactants, and each component has an effect on the phase behavior and solubilization of the micro-emulsion. When the surfactant in the micro-emulsion...Micro-emulsion usually consists of water, oil, surfactants and co-surfactants, and each component has an effect on the phase behavior and solubilization of the micro-emulsion. When the surfactant in the micro-emulsion system is quaternary ammonium cationic Gemini surfactant, the surfactant mainly combines with the anions in the salt. With the increase of salt concentration, the phase transformation of Winsor I → Winsor III → Winsor II occurred, but the optimum salinity and salt width are different because of the type of salt. The effects of 5 different kinds of monovalent anions, including C_6H_5SO_3^-, I-, Br-, NO_3^- and Cl-, on the phase behavior and solubilization of quaternary ammonium cationic Gemini micro-emulsion are researched by Winsor phase diagram. It is found that the effects of organic anions C_6H_5SO_3-and I-on the phase behavior and solubilization of quaternary ammonium cationic Gemini micro-emulsion are most significant, and the effects of Br-, NO_3^- and Cl-are less significant. Meanwhile, when the optimum solubilization is achieved, the amount of sodium benzoate is the least, indicating that the organic anion has stronger self-organization behavior with quaternary ammonium cationic Gemini surfactants.展开更多
Marine sediments from Lianshan Bay in Huludao, China, were studied in laboratory. A series of simulated experiments were carried out to investigate the influences of three kinds of anions CL^-, SO4^2- and HCO3^- on th...Marine sediments from Lianshan Bay in Huludao, China, were studied in laboratory. A series of simulated experiments were carried out to investigate the influences of three kinds of anions CL^-, SO4^2- and HCO3^- on the release ofCd, Pb, Cu and Zn from the sediments. The results showed that the sequences about the impact of the three anions were Cl^-〉HCO3^-〉SO4^2＋. The release potential of heavy metals in the presence of each anions was in the following order： Cd≥Cu 〉Zn≈Pb. The correlations were positive between CI content and the quantity of Cd released from the marine sediment, whereas there was no significant relationship between CI content and amount of Cu and Zn released. For SO4^2- and HCO3^-, the release of the heavy metals from marine sediments was not obvious.展开更多
Inserting corrosion inhibitors into a lamellar protective coating is an effective way to improve the corrosion resistance of metal substrates.In this work,two kinds of environmentally friendly organic acid anions,aspa...Inserting corrosion inhibitors into a lamellar protective coating is an effective way to improve the corrosion resistance of metal substrates.In this work,two kinds of environmentally friendly organic acid anions,aspartic acid(ASP)and lauric acid(La),were explored as corrosion inhibitors to in situ intercalate into the Zn Al-layered double hydroxides(Zn Al-LDHs)on AZ31 magnesium alloys by a facile one-step hydrothermal method.The morphology,composition,structure and the corrosion resistance of these two LDHs coating before and after corrosion experiment were investigated.It is found that both the two kinds of Zn Al-LDHs films consist of uniform and dense layered nanosheets(NSs),and the NSs of ZnAl-ASP-LDHs films grow vertically,but those of ZnAl-La-LDHs films exhibit a staggered tilted structure.The corrosion current density of the two Zn Al-LDHs films are two orders of magnitude lower than that of Mg alloy substrate.After one week’s immersion in NaCl solution,the NSs structure of two kind of ZnAl-LDHs films still remains the uniform and densely coverage on Mg alloy.Owing to the larger d(003)spacing,the ZnAl-La-LDHs have better ability to absorb Cl-and release interlayer anions than Zn Al-ASP-LDHs.These results indicate that the Zn Al-LDHs films intercalated with organic anions,specially La anions,can significantly improve the corrosion resistance of Mg alloy.展开更多
The growth kinetics of microarc oxidation(MAO)coatings on Ti6Al4V alloy was studied by designing an electrolyte with low PO_(4)^(3−)content and high B_(4)O_(7)^(2−)content,using scanning electron microscopy,transmissi...The growth kinetics of microarc oxidation(MAO)coatings on Ti6Al4V alloy was studied by designing an electrolyte with low PO_(4)^(3−)content and high B_(4)O_(7)^(2−)content,using scanning electron microscopy,transmission electron microscopy,X-ray diffraction,and potentiodynamic polarization.The results showed that B_(4)O_(7)^(2−)increased the spark intensity and dissolved most of the oxides at high temperatures.Then,a thicker barrier layer at the coating/substrate interface was produced,which increased the polarization resistance of the coating.PO_(4)^(3−)at a low concentration also promoted the uniform growth of the MAO coating and the formation of hat-shaped holes in the outer deposition layer.The thickness of the MAO coatings obtained in Na_(2)B_(4)O_(7) electrolytes exhibited an exponential increase with time at spark discharge stage,while that of the MAO coating obtained in phosphate–tetraborate electrolytes showed a linear trend as the PO_(4)^(3−)content increased.展开更多
MgH_(2) is regarded as a potential hydrolysis material for the hydrogen generation due to its high theoretical hydrogen yield,abundant source on earth and environmentally friendly hydrolysates.However,the quickly form...MgH_(2) is regarded as a potential hydrolysis material for the hydrogen generation due to its high theoretical hydrogen yield,abundant source on earth and environmentally friendly hydrolysates.However,the quickly formed passive magnesium hydroxide layer on the surface of MgH_(2) will hinder its further hydrolysis reaction,leading to sluggish reaction kinetics and low H_(2) yield.In this paper,we explore the improvement of different anions and cations in solutions for the hydrolysis of MgH_(2).It is found that the cations in the solution promote the reaction rate of MgH_(2) hydrolysis through the hydrolysate-induced growth effect,among which the fastest hydrogen yield can get 1664 m L/g within a few minutes in the Fe_(2)(SO_(4))_(3) solution.As for the anions,it enables different microstructures of the Mg(OH)_(2) hydrolysate which give rise to enhanced water utilization.Specially,for the mixed 0.5 M MgCl_(2)+0.05 M MgSO_(4) solution,the water utilization rate attains the optimum value of 51.3%,much higher than that of the single MgCl_(2) or MgSO_(4) solutions.These findings are of great significance for the application of MgH_(2) hydrolysis as hydrogen generation.展开更多
A laboratory incubation experiment was conducted to elucidate the effects of associated anions on toxicity of cadmium applied to microbial biomass in the red soil. Cadmium was applied at six different levels, i.e., 0 ...A laboratory incubation experiment was conducted to elucidate the effects of associated anions on toxicity of cadmium applied to microbial biomass in the red soil. Cadmium was applied at six different levels, i.e., 0 (background), 5, 15, 30, 60 and 100 μg-1 soil in the form of either cadmium acetate or cadmium chloride.Application of cadmium as cadmium acetate markedly reduced the soil microbial biomass carbon compared to cadmium applied as cadmium chloride at all the tested levels. Similarly, organic carbon to biomass carbon ratio in the soil was markedly increased by increasing the level of the cadmium in the soil as cadmium acetate,while the change was much smaller in the case of cadmium chloride at the same cadmium levels. The results suggested that due consideration should be given to the source of cadmium while deciding the cadmium levels in experiments.展开更多
An ion chromatography（IC） system coupled with on-line column-switching technique was used to determine anions ofμg/g levels in organic chemicals of analytical reagent grade.A novel polystyrene-divinylbenzene-carbon...An ion chromatography（IC） system coupled with on-line column-switching technique was used to determine anions ofμg/g levels in organic chemicals of analytical reagent grade.A novel polystyrene-divinylbenzene-carbon nanotube（PS-DVB-CNT） stationary phase was utilized for matrix elimination.A calibration study was conducted by preparing and analyzing eight concentrations（between 10 and 5000μg/L） of eight standards in deionized water.The linearity was between 0.9978 and 1.And the detection limits ranged from 1.54μg/L to 10.02μg/L.A spiking study was performed on two representative organic chemicals.The recoveries were between 84.3%and 119.6%.展开更多
It is well-known that the electrolytes can influence the electrochemical reduction of carbon dioxide(ERCO2)in aqueous media.In this work,we explore the effects of alkali metal cations and anions(Li^+,Na^+,K^+,Rb^+,Cs^...It is well-known that the electrolytes can influence the electrochemical reduction of carbon dioxide(ERCO2)in aqueous media.In this work,we explore the effects of alkali metal cations and anions(Li^+,Na^+,K^+,Rb^+,Cs^+,HCO3^-,Cl^-,Br^-,I^-)on the current density and product selectivity for the ERCO2 into formic acid(HCOOH)on the SnO2/carbon paper(Sn O2/C)electrode.Results of the ERCO2 experiments show that for the cations,the promotion effects on current density and faradaic efficiencies(FEs)are in the order of Li^+b Na^+b K^+b Cs^+b Rb^+.For the anions,the current density values are in the order of Na HCO3 b NaClb Na Br b Na I and KHCO3 b KCl≈KI b KBr,respectively,and that on the FEs for the formation of the HCOOH(FEHCOOH)is HCO3-b Cl-b Br-b I-.Based on this result,the effects of alkali metal cations and anions on ERCO2 are discussed.展开更多
The rate constants of reactions between the SO4^- radical and some common anions in atmospheric aqueous droplets e.g. Cl^-,NO^-, HSO3^- and HCO3^- were determined using the laser flash photolysis technique.Absorption ...The rate constants of reactions between the SO4^- radical and some common anions in atmospheric aqueous droplets e.g. Cl^-,NO^-, HSO3^- and HCO3^- were determined using the laser flash photolysis technique.Absorption spectra of SO4^- and the product radicals were also reported.The chloride ion was evaluated among all the anions to be the most efficient scavenger of SO4^-.The results may supply useful information for a better understanding of the vigorous radical-initiated reactions in atmospheric aqueous droplets such as clouds, rains or fogs.展开更多
We report the lithium ionic conductivities of closo –type complex hydrides synthesized from various molar ratios of lithium borohydride(LiBH4) and decaborane(B10H14) as starting materials. The prepared closo –type c...We report the lithium ionic conductivities of closo –type complex hydrides synthesized from various molar ratios of lithium borohydride(LiBH4) and decaborane(B10H14) as starting materials. The prepared closo –type complex hydrides comprised [B12H12]^2-, [B11H11]^2-, and [B10H10]^2- complex anions. In addition, increasing the LiBH4 content in the starting materials increased the amounts of [B11H11]^2- and [B10H10]^2-, leading to an improved ion conductivity of the prepared sample. The present study offers useful insights into strategies for controlling the complex anion composition in emerging solid electrolytes of closo-type complex hydrides at the molecular level, and improving their ionic conductivities.展开更多
As a vital nutrient closely related to the cance r-cells proliferation,phosphate anions have been paid great attention as a promising anticancer agent.Generally,the transport of phosphate anions depends on a protein t...As a vital nutrient closely related to the cance r-cells proliferation,phosphate anions have been paid great attention as a promising anticancer agent.Generally,the transport of phosphate anions depends on a protein transport system which is regulated by ion homeostasis regulations.Herein,we designed a reactive anionic nanocarrier based on black phosphorus nanosheets(BPs)and artesunate(ART),which could enter cells through endocytosis to generate phosphate anions,avoiding the regulation of cell homeostasis.The ionic nanocarrier was coated by polydopamine to defend BPs and ART and functionalized by folate(FA)and hyaluronic acid(HA)for targeting factor.With the anchoring groups FA/HA targeted the carrier into cells,polydopamine coating decomposed to expose ART for further generating reactive oxygen species(ROS)in cancer cell microenvironment,providing oxidation conditions.Next,ROS generated by ART makes BPs decompose to phosphate anions with effectively speed,giving rise to the destruction of ion homeostasis to induce necro sis and inhibit the proliferation for cancer cells.In consequence,this research provides novel idea and direction for the ionic carriers and tumor therapeutics.展开更多
Zn2Al layered double hydroxide pillared with Dawson polyoxometalates,P2W17ZO8-61(Z=Mn2+,Co2+,Ni2+,Cu2+,Zn2+)was prepared.A basal space ofca.16 nm indicates the intercalated Dawson ions to be oriented with their C2 axi...Zn2Al layered double hydroxide pillared with Dawson polyoxometalates,P2W17ZO8-61(Z=Mn2+,Co2+,Ni2+,Cu2+,Zn2+)was prepared.A basal space ofca.16 nm indicates the intercalated Dawson ions to be oriented with their C2 axis perpendicular to the double hydroxide layers(with the exception of P2W17ZnLDH).The IR and^(13)P MASNMR spectral reveal that the Dawson ions retain their integrity in the interlayer space of LDH.A preliminary study shows that these compounds are highly active catalysts for the oxidation of cyclohexene with molecular oxygen.展开更多
基金supported by the National Key Research and Development Program of China(2023YFB2406100)the National Natural Science Foundation of China(Grant No.22075062 and U23A20573)+6 种基金the Heilongjiang Touyan Team(Grant No.HITTY20190033)the Heilongjiang Postdoctoral Financial Assistance(Grant No.LBH-Z23137)the Postdoctoral Fellowship Program of CPSF(Grant No.GZC20233448)the China Postdoctoral Science Foundation(Grant No.2024M754198)the Shenzhen Science and Technology Program(KCXST20221021111216037)the Fundamental Research Funds for the Central Universities(Grant No.FRFCU5710051922)the program of “Open bidding for selecting the best candidates”(Grant No.2023JCA06)from Jiangxi Fuzhou Municipal Government。
文摘NASICON-type vanadium fluorophosphate is a promising cathode for sodium-ion batteries.Yet,the thermally-driven loss of undercoordinated dangling fluorine anions weakens its structural stability,which triggers severe framework distortion from interconnected double-octahedral to isolated local octahedral units,as well as a degeneracy of t_(2g) electronic configuration of vanadium(V)3d orbit.In this work,it is clarified that such a degenerate state undergoes spontaneous lattice evolution to reduce the system energy,which causes a low crystalline symmetry and a parasitic V^(4+)/V^(3+)redox reaction in the low-voltage region.Herein,an anion-coordination regulation strategy is developed to suppress this degeneration by anchoring fluorine anions in the double-octahedral[V_(2)O_(8)F_(3)]framework.Density functional theory calculations and in-situ techniques track the F-anion-driven structural evolution and charge compensation mechanisms,revealing that this strategy mitigates detrimental phase segregation during the initial desodiation stage and enhances the Na^(+)diffusion kinetic rate over a factor of 100.Concurrently,this strategy releases the V^(4+)/V^(3+)redox kinetics by eliminating the parasitic low-voltage plateau.The full-cell assembled with the optimized fluorophosphate cathode delivers an increase of 50%in discharge capacity and stable two-voltage-plateau behavior,enabled by its double-octahedral[V_(2)O_(8)F_(3)]polyanionic structure that facilitates unimpeded three-dimensional(3D)Na^(+)transport.By correlating anion-coordination stability with orbital-level charge compensation,this work establishes a universal paradigm for highperformance polyanionic cathodes,positioning it as a competitive candidate for battery applications.
基金supported by the National Natural Science Foundation of China(22478422,22238012,and 22178384)Science Foundation of China University of Petroleum,Beijing(2462024QNXZ003)CHN Energy Investment Group(GJNY23-23)。
文摘Designing transition metal nickel-cobalt-based battery-type electrode materials driven by anions is crucial for achieving rapid OH-ion transport under electrochemical activation conditions,thereby improving capacitance performance.Herein,borate anions are selected through theoretical calculations,and twodimensional(2D)defect-rich amorphous nickel-cobalt-based borate is synthesized via a facile chemical reduction method.Under potentiostatic modification,activated products(NCB-G-E)are obtained.In situ Raman spectra reveal that electron-deficient borate extracts electrons from metal centers,facilitating the oxidation state transition of Ni and Co.Theoretical calculations show that in situ adsorbed borate regulates the d-band centers of metal sites,enhancing OH^(-)intermediate adsorption.Meanwhile,borate anion adsorption accelerates the deprotonation and activation processes.Electrochemical tests demonstrate that NCB-G-E displays superior capacitance performance,with a high quality specific capacity of383.3 mA h g^(-1)and 65% retention rate at 30 A g^(-1),surpassing most nickel-cobalt-based electrodes.The assembled asymmetric supercapacitor presents an impressive energy density of 68.2 Wh kg^(-1)and good cycling stability.This work highlights the role of electron-deficient borate in tuning metal band structure and promoting oxidation state transition through synergistic defect advantages,offering new prospects for advanced battery-type energy storage materials.
文摘In order to find the optimal anions and cations for designing energetic salts with excellent detonation properties,the properties of 140 salts formed from the anions(A–G)of 3,3′-dinitroamino-4,4′-azoxyfurazan(DAAF)derivatives substituted with the—NH_(2),—N_(3) or—NO_(2) group and the cations(1–20)of guanidine,triazole,or tetrazole derivatives were investigated by means of density-functional theory.The predicted densities,heats of formation,detonation velocities(D),and detonation pressures(P)of 140 salts were 11.72 to 2.06 g·cm ^(−3),570.2 to 2333.4 kJ·mol^(−1),8.29 to 10.02 km·s^(−1) and 30.16 to 47.57 GPa,respectively.Most of the salts had better detonation properties than the widely used hexahydro-1,3,5-trinitro-1,3,5-triazine(RDX).Salts containing—NO_(2) group anions(C and F)have better detonation properties(D is 8.88 to 10.02 km·s^(−1) and P is 35.75 to 47.75 GPa)than other salts.Salts containing the cations NH_(4)^(+)(1),NH_(3)OH^(+)(2)and CH_(2)N_(4)NO_(2)^(+)(20)had good detonation properties(D is 9.38 to 10.02 km·s^(−1) and P is 40.72 to 47.75 GPa).Depending on the detonation properties,anions(C and F)and cations(1,2 and 20)are the recommended ions for the generation of energetic salts.
基金supported by the National Natural Science Foundation of China(Nos.52222317,21902144,52225208)the“Leading Innovative and Entrepreneur Team Introduction Program of Zhejiang”(No.2020R01002)+1 种基金the Natural Science Foundation of Zhejiang Province(No.LZ23E020002)the Fundamental Research Funds for the Provincial Universities of Zhejiang(No.RFC2023002).
文摘Anion modification has been considered as a strategy to improve water splitting efficiency upon oxygen evolution reaction(OER).However,constructing a novel catalysis system with high catalytic activity and precise structures is still a huge challenge due to the tedious procedure of precursor synthesis and anion selection.Here,a bimetallic(FeNi)nanowire self-assembled superstructure was synthesized using the Hoffmann rearrangement method,and then functionalized with four anions(P,Se,S,and O).Notably,the Fe_(3)Se_(4)/Ni_(3)Se_(4) catalyst shows a high conductivity,enhances the adsorption of intermediate products,accelerates the rate-determining step,and consequently results to improved electrocatalytic performance.Using the Fe_(3)Se_(4)/Ni_(3)Se_(4) catalyst exhibits enhanced performance with overpotential of 316mV at 10 mA/cm^(2),in stark contrast to Fe_(2) P/Ni_(2)P(357mV),Fe_(7)S_(8)/NiS(379 mV),and Fe_(3)O_(4)/NiO(464 mV).Moreover,the formation mechanism of superstructure and the relationship between electronegativities and electrocatalytic properties,are elucidated.Accordingly,this work provides an efficient approach to Hoffmann-type coordination polymer catalyst for oxygen evolution towards a near future.
基金supports from the National Natural Science Foundation of China(No.22173089,No.21827804,and No.22103075)the National Key R&D Program of China(No.2021YFA0716801 and No.2017YFA0303502).
文摘A plasma injection ion source has been de-veloped for the photoelectron velocity imag-ing studies of metal-containing anions.The source employs a pulse discharge nozzle for generating a plasma beam that perpendicu-larly crosses the master supersonic jet beam from a home-made pulsed piezo valve.The discharge nozzle is designed for high voltage gas discharge with efficient metal sputtering of the cathode,and thus plays a role in met-al atom and ion source.Supersonically jet-cooled anions can be produced in the master gas jet via reactions of the plasma products.The source is integrated into a photoelectron ve-locity imaging spectrometer.Test mass spectrometry experiments show that the ion source can efficiently produce transition metal containing anions,such as FeO_(m)^(-),CuO_(m)^(-),CuC_(n)^(-),CuC_(n)O_(m)^(-).The photoelectron imaging results by photodetachment of O-show that the pho-toelectron energy resolution of the whole instrument isΔE/E≈2.3%,and the results of FeO^(-)indicate that internal temperatures of anions from the source could be efficiently cooled down.
基金Project(41371475)supported by the National Natural Science Foundation of ChinaProject(201509048)supported by the Environmental Protection’s Special Scientific Research for Chinese Public Welfare Industry
文摘Bauxite residue is a highly alkaline waste containing soluble alkaline anions,which can cause environmental concerns.The optimal leaching conditions,distribution of alkaline anions,types of pivotal alkaline anions and their dissolution behaviors were investigated based on the combination of single factors-orthogonal experiments and leaching stage experiment.Using a two-stage leaching,86%of the soluble alkaline anions(CO3^2-,HCO4^-,Al(OH)4^-,OH^-)were leached with a L/S ratio of 2 mL/g,at 30℃,over 23 h.During the first stage of leaching,approximately 88%of alkaline anions were leached from the dissolution of free alkali(Na OH,carbonate,bicarbonate,NaAl(OH)4)with the rest originating from the dissolution of alkaline minerals(calcite,cancrinite and hydrogarnet).Supernatant alkalinity was 69.78 mmol/L with CO3^2-accounting for 75%.Furthermore,carbonate leaching was controlled by solid film diffusion using the Stumm Model with an apparent activation energy of 10.24 kJ/mol.
基金supported by the National Natural Science Foundation of China(Nos.41701587,41877511)the Open Sharing Fund for the Large-scale Instruments,Euipments of Central South University(No.CSUZC201904)the Fundamental Research Funds for the Central Universities of Central South University
文摘A column leaching experiment was used to investigate the efficacy of amendments on their ability to remove alkaline anions and metal ions from bauxite residue leachates.Treatments included,simulated acid rain (AR),phosphogypsum + vermicompost (PVC),phosphogypsum + vermicompost + simulated acid rain (PVA),and biosolids + microorganisms (BSM) together with controls (CK).Results indicated that amendment could effectively reduce the leachate pH and EC values,neutralize OH-,CO32-,HCO3-,and water soluble alkali,and suppress arsenic (As) content.Correlation analysis revealed significant linear correlations with pH and concentrations of OH-,CO32-,HCO3-,water-soluble alkali,and metal ions.BSM treatment showed optimum results with neutralizing anions (OH-,CO32-,and HCO3-),water soluble alkali,and removal of metal ions (Al,As,B,Mo,V,and Na),which was attributed to neutralization from the generation of small molecular organic acids and organic matter during microbial metabolism.BSM treatment reduced alkaline anions and metal ions based on neutralization reactions in bauxite residue leachate,which reduced the potential pollution effects from leachates on the soil surrounding bauxite residue disposal areas.
基金financially supported by the National Natural Science Foundation of China(No.U1301212)the Strategic Priority Research Program of the Chinese Academy of Sciences(No.XDB15030202)
文摘Aluminum （AI） toxicity and phosphorous （P） deficiency are two major limiting factors for plant growth on acidic soils. Thus, the physiological mechanisms for AJ tolerance and P acquisition have been intensively studied. A commonly observed trait is that plants have developed the ability to utilize organic acid anions （OAs; mainly malate, citrate and oxalate） to combat AI toxicity and P deficiency. OAs secreted by roots into the rhizosphere can externally chelate Al^3＋ and mobilize phosphate （Pi）, while OAs synthesized in the cell can internally sequester Al^3＋ into the vacuole and release free Pi for metabolism. Molecular mechanisms involved in OA synthesis and transport have been described in detail. Ensuing genetic improvement for AI tolerance and P efficiency through increased OA exudation and/or synthesis in crops has been achieved by transgenic and marker-assisted breeding. This review mainly elucidates the crucial roles of OAs in plant Al tolerance and P efficiency through summarizing associated physiological mechanisms, molecular traits and genetic manipulation of crops.
基金Supported by China Petroleum Science and Technology Innovation Fund(2017D-5007-0601)State Key Laboratory of Heavy Oil Processing and China University of Petroleum(East China)2018 Graduate Engineering Innovation Project Found(SLKZZ-2017002)
文摘Micro-emulsion usually consists of water, oil, surfactants and co-surfactants, and each component has an effect on the phase behavior and solubilization of the micro-emulsion. When the surfactant in the micro-emulsion system is quaternary ammonium cationic Gemini surfactant, the surfactant mainly combines with the anions in the salt. With the increase of salt concentration, the phase transformation of Winsor I → Winsor III → Winsor II occurred, but the optimum salinity and salt width are different because of the type of salt. The effects of 5 different kinds of monovalent anions, including C_6H_5SO_3^-, I-, Br-, NO_3^- and Cl-, on the phase behavior and solubilization of quaternary ammonium cationic Gemini micro-emulsion are researched by Winsor phase diagram. It is found that the effects of organic anions C_6H_5SO_3-and I-on the phase behavior and solubilization of quaternary ammonium cationic Gemini micro-emulsion are most significant, and the effects of Br-, NO_3^- and Cl-are less significant. Meanwhile, when the optimum solubilization is achieved, the amount of sodium benzoate is the least, indicating that the organic anion has stronger self-organization behavior with quaternary ammonium cationic Gemini surfactants.
基金The National Basic Research Program (973) of China (No. 2004CB3418501)
文摘Marine sediments from Lianshan Bay in Huludao, China, were studied in laboratory. A series of simulated experiments were carried out to investigate the influences of three kinds of anions CL^-, SO4^2- and HCO3^- on the release ofCd, Pb, Cu and Zn from the sediments. The results showed that the sequences about the impact of the three anions were Cl^-〉HCO3^-〉SO4^2＋. The release potential of heavy metals in the presence of each anions was in the following order： Cd≥Cu 〉Zn≈Pb. The correlations were positive between CI content and the quantity of Cd released from the marine sediment, whereas there was no significant relationship between CI content and amount of Cu and Zn released. For SO4^2- and HCO3^-, the release of the heavy metals from marine sediments was not obvious.
基金supported by the Natural Science Foundation of Chongqing(cstc2019jcyjmsxm X0566,cstc2018jcyj AX0450,cstc2018jcyj A2923,cstc2017jcyj AX0393)Projects of President Foundation of Chongqing University(2019CDXZWL002)+3 种基金Fundamental Research Funds for the Central Universities(2019CDXYWL0029,2018CDJDWL0011,106112017CDJQJ328839,106112016CDJZR288805)Science and Technology Research Program of Chongqing Municipal Education Commission(KJKJQN201800102,KJQN201800619,KJ1703042)NSFC(11544010,11374359,11304405 and 1155305)the Sharing Fund of Large-scale Equipment of Chongqing University(201903150094)
文摘Inserting corrosion inhibitors into a lamellar protective coating is an effective way to improve the corrosion resistance of metal substrates.In this work,two kinds of environmentally friendly organic acid anions,aspartic acid(ASP)and lauric acid(La),were explored as corrosion inhibitors to in situ intercalate into the Zn Al-layered double hydroxides(Zn Al-LDHs)on AZ31 magnesium alloys by a facile one-step hydrothermal method.The morphology,composition,structure and the corrosion resistance of these two LDHs coating before and after corrosion experiment were investigated.It is found that both the two kinds of Zn Al-LDHs films consist of uniform and dense layered nanosheets(NSs),and the NSs of ZnAl-ASP-LDHs films grow vertically,but those of ZnAl-La-LDHs films exhibit a staggered tilted structure.The corrosion current density of the two Zn Al-LDHs films are two orders of magnitude lower than that of Mg alloy substrate.After one week’s immersion in NaCl solution,the NSs structure of two kind of ZnAl-LDHs films still remains the uniform and densely coverage on Mg alloy.Owing to the larger d(003)spacing,the ZnAl-La-LDHs have better ability to absorb Cl-and release interlayer anions than Zn Al-ASP-LDHs.These results indicate that the Zn Al-LDHs films intercalated with organic anions,specially La anions,can significantly improve the corrosion resistance of Mg alloy.
文摘The growth kinetics of microarc oxidation(MAO)coatings on Ti6Al4V alloy was studied by designing an electrolyte with low PO_(4)^(3−)content and high B_(4)O_(7)^(2−)content,using scanning electron microscopy,transmission electron microscopy,X-ray diffraction,and potentiodynamic polarization.The results showed that B_(4)O_(7)^(2−)increased the spark intensity and dissolved most of the oxides at high temperatures.Then,a thicker barrier layer at the coating/substrate interface was produced,which increased the polarization resistance of the coating.PO_(4)^(3−)at a low concentration also promoted the uniform growth of the MAO coating and the formation of hat-shaped holes in the outer deposition layer.The thickness of the MAO coatings obtained in Na_(2)B_(4)O_(7) electrolytes exhibited an exponential increase with time at spark discharge stage,while that of the MAO coating obtained in phosphate–tetraborate electrolytes showed a linear trend as the PO_(4)^(3−)content increased.
基金supported by the National Key Research and Development Program of China(2017YFA0204600)the National Science Fund for Distinguished Young Scholars(51625102)+2 种基金the National Natural Science Foundation of China(51971065)the Innovation Program of Shanghai Municipal Education Commission(2019–01–07–00–07-E00028)the financial support from ARC(DP170101773)。
文摘MgH_(2) is regarded as a potential hydrolysis material for the hydrogen generation due to its high theoretical hydrogen yield,abundant source on earth and environmentally friendly hydrolysates.However,the quickly formed passive magnesium hydroxide layer on the surface of MgH_(2) will hinder its further hydrolysis reaction,leading to sluggish reaction kinetics and low H_(2) yield.In this paper,we explore the improvement of different anions and cations in solutions for the hydrolysis of MgH_(2).It is found that the cations in the solution promote the reaction rate of MgH_(2) hydrolysis through the hydrolysate-induced growth effect,among which the fastest hydrogen yield can get 1664 m L/g within a few minutes in the Fe_(2)(SO_(4))_(3) solution.As for the anions,it enables different microstructures of the Mg(OH)_(2) hydrolysate which give rise to enhanced water utilization.Specially,for the mixed 0.5 M MgCl_(2)+0.05 M MgSO_(4) solution,the water utilization rate attains the optimum value of 51.3%,much higher than that of the single MgCl_(2) or MgSO_(4) solutions.These findings are of great significance for the application of MgH_(2) hydrolysis as hydrogen generation.
文摘A laboratory incubation experiment was conducted to elucidate the effects of associated anions on toxicity of cadmium applied to microbial biomass in the red soil. Cadmium was applied at six different levels, i.e., 0 (background), 5, 15, 30, 60 and 100 μg-1 soil in the form of either cadmium acetate or cadmium chloride.Application of cadmium as cadmium acetate markedly reduced the soil microbial biomass carbon compared to cadmium applied as cadmium chloride at all the tested levels. Similarly, organic carbon to biomass carbon ratio in the soil was markedly increased by increasing the level of the cadmium in the soil as cadmium acetate,while the change was much smaller in the case of cadmium chloride at the same cadmium levels. The results suggested that due consideration should be given to the source of cadmium while deciding the cadmium levels in experiments.
基金supported by National Natural Science Foundation of China(Nos.20775070, J0830413)Zhejiang Provincial Natural Science Foundation of China(Nos.R4080124,Y4090104,Y4090078)Zhejiang Qianjiang Project of Science and Technology for Competent People(No.2008R10028)
文摘An ion chromatography（IC） system coupled with on-line column-switching technique was used to determine anions ofμg/g levels in organic chemicals of analytical reagent grade.A novel polystyrene-divinylbenzene-carbon nanotube（PS-DVB-CNT） stationary phase was utilized for matrix elimination.A calibration study was conducted by preparing and analyzing eight concentrations（between 10 and 5000μg/L） of eight standards in deionized water.The linearity was between 0.9978 and 1.And the detection limits ranged from 1.54μg/L to 10.02μg/L.A spiking study was performed on two representative organic chemicals.The recoveries were between 84.3%and 119.6%.
基金financially supported by International Academic Cooperation and Exchange Program of Shanghai Science and Technology Committee(18160723600)Scientific Research and Technology Development Plan of Guangxi(GUIKE AD17195084)。
文摘It is well-known that the electrolytes can influence the electrochemical reduction of carbon dioxide(ERCO2)in aqueous media.In this work,we explore the effects of alkali metal cations and anions(Li^+,Na^+,K^+,Rb^+,Cs^+,HCO3^-,Cl^-,Br^-,I^-)on the current density and product selectivity for the ERCO2 into formic acid(HCOOH)on the SnO2/carbon paper(Sn O2/C)electrode.Results of the ERCO2 experiments show that for the cations,the promotion effects on current density and faradaic efficiencies(FEs)are in the order of Li^+b Na^+b K^+b Cs^+b Rb^+.For the anions,the current density values are in the order of Na HCO3 b NaClb Na Br b Na I and KHCO3 b KCl≈KI b KBr,respectively,and that on the FEs for the formation of the HCOOH(FEHCOOH)is HCO3-b Cl-b Br-b I-.Based on this result,the effects of alkali metal cations and anions on ERCO2 are discussed.
文摘The rate constants of reactions between the SO4^- radical and some common anions in atmospheric aqueous droplets e.g. Cl^-,NO^-, HSO3^- and HCO3^- were determined using the laser flash photolysis technique.Absorption spectra of SO4^- and the product radicals were also reported.The chloride ion was evaluated among all the anions to be the most efficient scavenger of SO4^-.The results may supply useful information for a better understanding of the vigorous radical-initiated reactions in atmospheric aqueous droplets such as clouds, rains or fogs.
基金supported by METX,JSPS KAKENHI (Grant numbers, 16K0 676 6, 17H0 6519, 17K18972, 18H01727, and JP18H05513)Collaborative Research Center on Energy Materials in IMR (E-IMR)Target Project 4 of WPI-AIMR, Tohoku University
文摘We report the lithium ionic conductivities of closo –type complex hydrides synthesized from various molar ratios of lithium borohydride(LiBH4) and decaborane(B10H14) as starting materials. The prepared closo –type complex hydrides comprised [B12H12]^2-, [B11H11]^2-, and [B10H10]^2- complex anions. In addition, increasing the LiBH4 content in the starting materials increased the amounts of [B11H11]^2- and [B10H10]^2-, leading to an improved ion conductivity of the prepared sample. The present study offers useful insights into strategies for controlling the complex anion composition in emerging solid electrolytes of closo-type complex hydrides at the molecular level, and improving their ionic conductivities.
基金financially supported by the National Natural Science Foundation of China(No.21575055)the Fundamental Research Funds for the Central Universities(No.561220006)。
文摘As a vital nutrient closely related to the cance r-cells proliferation,phosphate anions have been paid great attention as a promising anticancer agent.Generally,the transport of phosphate anions depends on a protein transport system which is regulated by ion homeostasis regulations.Herein,we designed a reactive anionic nanocarrier based on black phosphorus nanosheets(BPs)and artesunate(ART),which could enter cells through endocytosis to generate phosphate anions,avoiding the regulation of cell homeostasis.The ionic nanocarrier was coated by polydopamine to defend BPs and ART and functionalized by folate(FA)and hyaluronic acid(HA)for targeting factor.With the anchoring groups FA/HA targeted the carrier into cells,polydopamine coating decomposed to expose ART for further generating reactive oxygen species(ROS)in cancer cell microenvironment,providing oxidation conditions.Next,ROS generated by ART makes BPs decompose to phosphate anions with effectively speed,giving rise to the destruction of ion homeostasis to induce necro sis and inhibit the proliferation for cancer cells.In consequence,this research provides novel idea and direction for the ionic carriers and tumor therapeutics.
文摘Zn2Al layered double hydroxide pillared with Dawson polyoxometalates,P2W17ZO8-61(Z=Mn2+,Co2+,Ni2+,Cu2+,Zn2+)was prepared.A basal space ofca.16 nm indicates the intercalated Dawson ions to be oriented with their C2 axis perpendicular to the double hydroxide layers(with the exception of P2W17ZnLDH).The IR and^(13)P MASNMR spectral reveal that the Dawson ions retain their integrity in the interlayer space of LDH.A preliminary study shows that these compounds are highly active catalysts for the oxidation of cyclohexene with molecular oxygen.
