To modify the stable thermodynamics and poor kinetics of magnesium hydride(MgH_(2))for solid-state hydrogen storage,MIL-100(Fe)was in situ fabricated on the surfaces of TiO_(2)nano-sheets(NS)by a self-assembly method,...To modify the stable thermodynamics and poor kinetics of magnesium hydride(MgH_(2))for solid-state hydrogen storage,MIL-100(Fe)was in situ fabricated on the surfaces of TiO_(2)nano-sheets(NS)by a self-assembly method,and the prepared TiO_(2)NS@MIL-100(Fe)presents an excellent catalytic effect on MgH_(2).The MgH_(2)+7wt.%TiO_(2)NS@MIL-100(Fe)composite can release hydrogen at 200℃,achieving a decrease of 150℃ compared to pure MgH_(2).Besides,the activation energy of dehydrogenation is decreased to 70.62 kJ/mol and 4 wt.%H_(2) can be desorbed within 20 min at a low temperature of 235℃.Under conditions of 100℃ and 3 MPa,MgH_(2)+7wt.%TiO_(2)NS@MIL-100(Fe)absorbs 5 wt.%of H_(2) in 10 min.Surprisingly,6.62 wt.%reversible capacity is maintained after 50 cycles.The modification mechanism is confirmed that the presence of oxygen vacancies and the synergistic effect of multivalent titanium in TiO_(2)NS@MIL-100(Fe)greatly enhance the kinetic and thermodynamic properties of MgH_(2).展开更多
Catalytic doping of magnesium hydride(MgH_(2))to improve its hydrogen ab/desorption kinetic properties is considered to be an effective and feasible method.In solid-phase catalysis,the extent of contact between the ca...Catalytic doping of magnesium hydride(MgH_(2))to improve its hydrogen ab/desorption kinetic properties is considered to be an effective and feasible method.In solid-phase catalysis,the extent of contact between the catalyst and the substrate determines the catalytic reaction in a great sense.With large specific surface area and abundant active sites,two-dimensional(2D)nanomaterials are promising catalysts for MgH_(2)via providing numerous pathways for the diffusion and dissociation of hydrogen.In this regard,2D NiMn-based layered double hydroxide and layered metallic oxide(LMO)are designed and introduced into MgH_(2)to improve its hydrogen storage properties.Simultaneous enhancement in interfacial contact,desorption temperature and kinetics are achieved.The MgH_(2)+9wt%Ni3Mn-LMO composites begin to discharge hydrogen at only 190℃and 6.10wt%H_(2)could be charged in 600 s at 150℃.The activation energy for de/hydrogenation is reduced by 42.43%and 46.56%,respectively,compared to pure MgH_(2).Even at a low operating temperature of 235℃,the modified system was still able to release 4.44wt%H_(2)in an hour,which has rarely been reported in previous studies.Microstructure observations and density functional theory calculations revealed that first,the hydrogen pumping effect of Mg_(2)Ni/Mg_(2)NiH_(4) promotes the adsorption and desorption of hydrogen molecules on the surface of MgH_(2),second,MnOx drew electrons from Mg_(2)Ni,producing a new Density of State structure with a lower d-bond center.This unique change further strengthens the Mg_(2)Ni/Mg_(2)NiH_(4) pump effect on MgH_(2).Our work indicates that the application of 2D metal-based catalysts is a feasible and promising approach towards MgH_(2)for solid-state hydrogen storage to meet technical and scientific requirements.展开更多
Na_(3)V_(2)O_(2x)(PO_(4))_(2)F_(3-2x)(NVPOF)is considered one of the most promising cathode materials for sodium-ion batteries due to its favorable working potential and optimal theoretical specific capacity.However,i...Na_(3)V_(2)O_(2x)(PO_(4))_(2)F_(3-2x)(NVPOF)is considered one of the most promising cathode materials for sodium-ion batteries due to its favorable working potential and optimal theoretical specific capacity.However,its long-cycle and rate performance are significantly constrained by the low Na^(+)electronic conductivity of NVPOF.Furthermore,the prevalent self-discharge phenomenon restricts its applicability in practical applications.In this paper,the cathode material Na_(3)V_(1.84)Fe_(0.16)(PO_(4))_(2)F_(3)(x=0.16)was synthesized by quantitatively introducing Fe^(3+)into the V-site of NVPOF.The introduction of Fe^(3+)significantly reduced the original bandgap and the energy barrier of NVPOF,as demonstrated through density functional theory calculations(DFT).When material x=0.16 is employed as the cathode material for the sodium-ion battery,the Na^(+)diffusion coefficient is significantly enhanced,exhibiting a lower activation energy of42.93 kJ mol^(-1).Consequently,material x=0.16 exhibits excellent electrochemical performance(rate capacity:57.32 mA h g^(-1)@10 C,cycling capacity:the specific capacity of 101.3 mA h g^(-1)can be stably maintained after 1000 cycles at 1 C current density).It can also achieve a full charge state in only2.39 min at a current density of 10 C while maintaining low energy loss across various stringent self-discharge tests.In addition,the sodium storage mechanism associated with the three-phase transition of Na_(X)V_(1.84)Fe_(0.16)(PO_(4))_(2)F_(3)(X=1,2,3)was elucidated by a series of experiments.In conclusion,this study presents a novel approach to multifunctional advanced sodium-ion battery cathode materials.展开更多
A multivalent inactivated Escherichia coli vaccine for forest musk deer by using serotypes O4,O26,and O139 with Al（OH）3 adjuvant was prepared.The vaccine did not cause any adverse reactions in forest musk deer.The i...A multivalent inactivated Escherichia coli vaccine for forest musk deer by using serotypes O4,O26,and O139 with Al（OH）3 adjuvant was prepared.The vaccine did not cause any adverse reactions in forest musk deer.The immunogenic effects of the vaccine were experimentally investigated in pregnant and young forest musk deer.The serum antibody titers of pregnant and young forest musk deer were determined by performing the micro-agglutination test.The serum antibody titers of pregnant forest musk deer were more stable from 35th to 68th d after the third vaccination,and the serum antibody titers of four pregnant forest musk deer were maintained 25,25,25,and 24 on 68th d after the third vaccination.Young forest musk deer showed serum antibody titers which were obtained due to nursing.Young forest musk deer were administered the first intramuscular vaccine injection at an age of approximately 60 days due to a fall in maternal antibody titers.The serum antibody titers of young forest musk deer were higher after the third vaccination and maintained at approximately the same level until they were 137 days old.The maternal antibodies and the antibodies produced by young forest musk deer could be helpful for protecting the young musk deer from the infections of pathogenic Escherichia coli strains（serotypes O4,O26,and O139）for 137 days after birth（during the nursing period and the period when the forest musk deer were susceptible to diseases）.展开更多
In this paper we introduce some new subclesses of meromorphic multivalent functions. Inclusion relations between these classes, the class preserving integral operators and coefficient estimates are obtained.
Hand,foot,and mouth disease(HFMD)recently emerged as a global public threat.The licensure of inactivated enterovirus A71(EV-A71)vaccine was the first step in using a vaccine to control HFMD.New challenges arise from c...Hand,foot,and mouth disease(HFMD)recently emerged as a global public threat.The licensure of inactivated enterovirus A71(EV-A71)vaccine was the first step in using a vaccine to control HFMD.New challenges arise from changes in the pathogen spectrum while vaccines directed against other common serotypes are in the preclinical stage.The mission of a broad-spectrum prevention strategy clearly favors multivalent vaccines.The development of multivalent vaccines was attempted via the simple combination of potent monovalent vaccines or the construction of chimeric vaccines comprised of epitopes derived from different virus serotypes.The present review summarizes recent advances in HFMD vaccine development and discusses the next steps toward a safe and effective HFMD vaccine that is capable of establishing a crossprotective antibody response.展开更多
The constant increase in global energy demand and stricter environmental standards are calling for advanced energy storage technologies that can store electricity from intermittent renewable sources such as wind,solar...The constant increase in global energy demand and stricter environmental standards are calling for advanced energy storage technologies that can store electricity from intermittent renewable sources such as wind,solar,and tidal power,to allow the broader implementation of the renewables.The gridoriented sodium-ion batteries,potassium ion batteries and multivalent ion batteries are cheaper and more sustainable alternatives to Li-ion,although they are still in the early stages of development.Additional optimisation of these battery systems is required,to improve the energy and power density,and to solve the safety issues caused by dendrites growth in anodes.Electrolyte,one of the most critical components in these batteries,could significantly influence the electrochemical performances and operations of batteries.In this review,the definitions and influences of three critical components(salts,solvents,and additives)in electrolytes are discussed.The significant advantages,challenges,recent progress and future optimisation directions of various electrolytes for monovalent and multivalent ions batteries(i.e.organic,ionic liquid and aqueous liquid electrolytes,polymer and inorganic solid electrolytes)are summarised to guide the practical application for grid-oriented batteries.展开更多
Macroscopic supramolecular assembly(MSA)has been a recent progress in supramolecular chemistry.MSA mainly focuses on studies of the building blocks with a size beyond ten micrometers and the non-covalent interactions ...Macroscopic supramolecular assembly(MSA)has been a recent progress in supramolecular chemistry.MSA mainly focuses on studies of the building blocks with a size beyond ten micrometers and the non-covalent interactions between these interactive building blocks to form ordered structures.MSA is essential to realize the concept of"self-assembly at all scales"by bridging most supramolecular researches at molecular level and at macroscopic scale.This review summaries the development of MSA,the basic design principle and related strategies to achieve MSA and potential applications.Correspondingly,we try to elucidate the correlations and differences between"macroscopic assembly"and MSA based on intermolecular interactions;the design principle and the underlying assembly mechanism of MSA are proposed to understand the reported MSA behaviors;to demonstrate further applications of MSA,we introduce some methods to improve the ordered degree of the assembled structures from the point of precise assembly and thus envision some possible fields for the use of MSA.展开更多
Aqueous multivalent-metal-ion intercalation chemistries hold genuine promise to develop safe and powerful microbatteries for potential use in many miniaturized electronics.However,their development is beset by state-o...Aqueous multivalent-metal-ion intercalation chemistries hold genuine promise to develop safe and powerful microbatteries for potential use in many miniaturized electronics.However,their development is beset by state-of-the-art electrode materials having practical capacities far below their theoretical values.Here we demonstrate that high compatibility between layered transition-metal oxide hosts and hydrated cation vips substantially boost their multi-electron-redox reactions to offer higher capacities and rate capability,based on typical bipolar vanadium oxides preintercalated with hydrated cations(M_(x)V_(2)O_(5)).When seamlessly integrated on Au current microcollectors with a three-dimensional bicontinuous nanoporous architecture that offers high pathways of electron transfer and ion transport,the constituent Zn_(x)V_(2)O_(5) exhibits specific capacity of as high as∼527 mAh g^(−1) at 5 mV s^(−1) and retains∼300 mAh g^(−1) at 200 mV s^(−1) in 1 M ZnSO_(4) aqueous electrolyte,outperforming the M_(x)V_(2)O_(5)(M=Li,Na,K,Mg).This allows aqueous rechargeable zinc-ion microbatteries constructed with symmetric nanoporous Zn_(x)V_(2)O_(5)/Au interdigital microelectrodes as anode and cathode to show high-density energy of∼358 mWh cm^(−3)(a value that is forty-fold higher than that of 4 V/500μAh Li thin film battery)at high levels of power delivery.展开更多
Flexible aqueous batteries have been thriving with the growing demand for wearable and portable electrical devices.In particular,flexible aqueous mul tivalent ion batteries(FAMIBs),the charge carriers of which include...Flexible aqueous batteries have been thriving with the growing demand for wearable and portable electrical devices.In particular,flexible aqueous mul tivalent ion batteries(FAMIBs),the charge carriers of which include Zn^(2+),Al^(3+),Mg^(2+),and Ca^(2+),have great potential for development owing to their high safety,high elemental abundance in the Earth's crust,and a multi-electron redox mechanism with a high theoretical specific capacity.Therefore,for a comprehensive understanding of this developing field,it is necessary to summarize the recent research progress of FAMIBs in a timely manner.Herein,the advancements of the state-of-the-art FAMIBs are reviewed,and the prospects toward this field are also proposed.This study focuses on the rational material and configuration design for FAMIBs in recent studies to achieve high battery performances under deformation conditions,which is elaborated on by classification of the anode,cathode,hydrogel electrolyte,and configurations of FAMIBs.Besides,the electrochemical performance of FAMIBs under flexible conditions is also reviewed from the perspective of their working voltage,specific capacity,and cycling stability.Finally,the ap proaches to improve the performance of FAMIBs are comprehensively eval uated,followed by the outlook on the challenges and opportunities in future development of FAMIBs.展开更多
Multivalent metal-sulfur(M-S,where M=Mg,Al,Ca,Zn,Fe,etc.)batteries offer unique opportunities to achieve high specific capacity,elemental abundancy and cost-effectiveness beyond lithium-ion batteries(LIBs).However,the...Multivalent metal-sulfur(M-S,where M=Mg,Al,Ca,Zn,Fe,etc.)batteries offer unique opportunities to achieve high specific capacity,elemental abundancy and cost-effectiveness beyond lithium-ion batteries(LIBs).However,the slow diffusion of multivalent-metal ions and the shuttle of soluble polysulfide result in impoverished reversible capacity and limited cycle performance of M-S(Mg-S,Al-S,Ca-S,Zn-S,Fe-S,etc.)batteries.It is a necessity to optimize the electrochemical performance,while deepening the understanding of the unique electrochemical reaction mechanism,such as the intrinsic multi-electron reaction process,polysulfides dissoluti on and the in stability of metal an odes.To solve these problems,we have summarized the state-of-the-art progress of current M-S batteries,and sorted out the existing challen ges for different multivalent M-S batteries according to sulfur cathode,electrolytes,metallic an ode and current collectors/separators,respectively.In this literature,we have surveyed and exemplified the strategies developed for better M-S batteries to strengthen the application of green,cost-effective and high energy density M-S batteries.展开更多
Multivalent polymer chains exhibit excellent prospect in biomedical applications by serving as therapeutic agents. Using three-dimensional （3D） Langevin dynamics simulations, we investigate adsorption behaviors of m...Multivalent polymer chains exhibit excellent prospect in biomedical applications by serving as therapeutic agents. Using three-dimensional （3D） Langevin dynamics simulations, we investigate adsorption behaviors of multivalent polymer chains to a surface with receptors. Multivalent polymer chains display superselective adsorption. Furthermore, the range of density of surface receptors at which a multivalent polymer chain displays a superselective behavior, narrows down for chains with higher density of ligands. Meanwhile, the optimal density of surface receptors where the highest superselectivity is achieved, decreases with increasing the density of ligands. Then, the conformational properties of bound multivalent chains are studied systematically. Interestingly, we find that the equilibrium radius of gyration Rg and its horizontal component have a maximum as a function of the density of surface receptors. The scaling exponents of Rg with the length of chain suggest that with increasing the density of surface receptors., the conformations of a bound multivalent polymer chain first fall in between those of a two-dimensional （2D） and a 3D chain, while it is slightly collapsed subsequently.展开更多
Wearable self-powered systems integrated with energy conversion and storage devices such as solar-charging power units arouse widespread concerns in scientific and industrial realms.However,their applications are hamp...Wearable self-powered systems integrated with energy conversion and storage devices such as solar-charging power units arouse widespread concerns in scientific and industrial realms.However,their applications are hampered by the restrictions of unbefitting size matching between integrated modules,limited tolerance to the variation of input current,reliability,and safety issues.Herein,flexible solar-charging self-powered units based on printed Zn-ion hybrid micro-capacitor as the energy storage module is developed.Unique 3D micro-/nano-architecture of the biomass kelp-carbon combined with multivalent ion(Zn2+)storage endows the aqueous Zn-ion hybrid capacitor with high specific capacity(196.7 mAh g^−1 at 0.1 A g^−1).By employing an in-plane asymmetric printing technique,the fabricated quasi-solid-state Zn-ion hybrid microcapacitors exhibit high rate,long life and energy density up to 8.2μWh cm^−2.After integrating the micro-capacitor with organic solar cells,the derived self-powered system presents outstanding energy conversion/storage efficiency(ηoverall=17.8%),solar-charging cyclic stability(95%after 100 cycles),wide current tolerance,and good mechanical flexibility.Such portable,wearable,and green integrated units offer new insights into design of advanced self-powered systems toward the goal of developing highly safe,economic,stable,and long-life smart wearable electronics.展开更多
Zinc metal anodes(ZMA)have high theoretical capacities(820 mAh g−1 and 5855 mAh cm−3)and redox potential(−0.76 V vs.standard hydrogen electrode),similar to the electrochemical voltage window of the hydrogen evolution ...Zinc metal anodes(ZMA)have high theoretical capacities(820 mAh g−1 and 5855 mAh cm−3)and redox potential(−0.76 V vs.standard hydrogen electrode),similar to the electrochemical voltage window of the hydrogen evolution reaction(HER)in a mild acidic electrolyte system,facilitating aqueous zinc batteries competitive in next-generation energy storage devices.However,the HER and byproduct formation effectuated by water-splitting deteriorate the electrochemical performance of ZMA,limiting their application.In this study,a key factor in promoting the HER in carbon-based electrode materials(CEMs),which can provide a larger active surface area and guide uniform zinc metal deposition,was investigated using a series of threedimensional structured templating carbon electrodes(3D-TCEs)with different local graphitic orderings,pore structures,and surface properties.The ultramicropores of CEMs are the determining critical factors in initiating HER and clogging active surfaces by Zn(OH)2 byproduct formation,through a systematic comparative study based on the 3D-TCE series samples.When the 3D-TCEs had a proper graphitic structure with few ultramicropores,they showed highly stable cycling performances over 2000 cycles with average Coulombic efficiencies of≥99%.These results suggest that a well-designed CEM can lead to high-performance ZMA in aqueous zinc batteries.展开更多
In recent years,the pursuit of high-efficiency electrochemical storage technology,the multivalent metalion batteries (MIBs) based on aqueous electrolytes have been widely explored by researchers because of their safet...In recent years,the pursuit of high-efficiency electrochemical storage technology,the multivalent metalion batteries (MIBs) based on aqueous electrolytes have been widely explored by researchers because of their safety,environmental friendliness,abundant reserves and low price,and especially the merits in energy and power densities.This review firstly expounds on the problems existing in the electrode materials of aqueous multivalent MIBs (Zn^(2+),Mg^(2+),Al^(3+),Ca^(2+)),from the classical inorganic materials to the emerging organic compounds,and then summarizes the design strategies in bulk and interface structure of electrodes with favorable kinetics and stable cycling performance,especially laying the emphasis on the charge storage mechanism of cathode materials and dendrite-free Zinc anode from the aspect of electrolyte optimization strategies,which can be extended to other aqueous multivalent MIBs.Ultimately,the possible development directions of the aqueous multivalent MIBs in the future are provided,anticipating to provide a meaningful guideline for researchers in this area.展开更多
In this paper we derive certain sufficient conditions for starlikeness and convexity of order α of meromorphically multivalent functions in the punctured unit disk.
In recent years,multicolor cascade supramolecular assemblies with controllable topological morphology have become a research hotspot due to their wide application in light-emitting materials,cell imaging and other fie...In recent years,multicolor cascade supramolecular assemblies with controllable topological morphology have become a research hotspot due to their wide application in light-emitting materials,cell imaging and other fields.Herein,several kinds of macrocycles including cucurbiturils,calixarene and cyclodextrins are used as building blocks to construct fluorescent assemblies with anthryl-conjugated phenylpyridine(G),wherein cucurbit[8]uril(CB[8])and G can form nanowires at a stoichiometric ratio of n:n through host-vip encapsulation to form a non-covalent heterodimer.Significantly,the macrocycle confinement effect drastically enhances the fluorescence emission of G and emission peak generated bathochromic shift from 500 nm to 600 nm.When the supramolecular polymer is further assembled with amphiphilic calix[4]arene(SC_(4)A8),the fluorescence emission of G?CB[8]further increases to 1.4 times,accompanied by the morphological transformation from linear structure to nanorod structure.Subsequently,a very small amount of dye Cy5 is added to the assembly solution as an energy receptor,and the negatively charged G?CB[8]@SC_(4)A8 system is regarded as an energy donor.The efficient energy transfer process enables near-infrared(NIR)emission at 675 nm with 71%energy transfer efficiency(ΦET)at a donor/receptor ratio of 100:1.Finally,the cascade supramolecular assembly has been successfully applied to targeted imaging in the nucleus of HeLa and A549 cancer cells.展开更多
Rechargeable aluminum batteries(RABs),which use earth-abundant and high-volumetric-capacity metal anodes(8040 m Ah cm-3),have great potential as next-generation power sources because they use cheaper resources to deli...Rechargeable aluminum batteries(RABs),which use earth-abundant and high-volumetric-capacity metal anodes(8040 m Ah cm-3),have great potential as next-generation power sources because they use cheaper resources to deliver higher energies,compared to current lithium ion batteries.However,the mechanism of charge delivery in the newly developed,ionic liquid-based electrolytic system for RABs differs from that in conventional organic electrolytes.Thus,targeted research efforts are required to address the large overpotentials and cycling decay encountered in the ionic liquid-based electrolytic system.In this study,a nanoporous carbon(NPC)electrode with well-developed nanopores is used to develop a high-performance aluminum anode.The negatively charged nanopores can provide quenched dynamics of electrolyte molecules in the aluminum deposition process,resulting in an increased collision rate.The fast chemical equilibrium of anionic species induced by the facilitated anionic collisions leads to more favorable reduction reactions that form aluminum metals.The nanoconfinement effect causes separated nucleation and growth of aluminum nanoparticles in the multiple confined nanopores,leading to higher coulombic efficiencies and more stable cycling performance compared with macroporous carbon black and 2D stainless steel electrodes.展开更多
Recovery of alginate extracted from aerobic granular sludge(AGS)has given rise to a novel research direction.However,these extracted alginate solutions have a water content of nearly 100%.Alternately,ultrafiltration(U...Recovery of alginate extracted from aerobic granular sludge(AGS)has given rise to a novel research direction.However,these extracted alginate solutions have a water content of nearly 100%.Alternately,ultrafiltration(UF)is generally used for concentration of polymers.Furthermore,the introduction of multivalent metal ions into alginate may provide a promising method for the development of novel nanomaterials.In this study,membrane fouling mitigation by multivalent metal ions,both individually and in combination,and properties of recycled materials were investigated for UF recovery of sodium alginate(SA).The filtration resistance showed a significantly negative correlation with the concentration of metal ions,arranged in the order of Mg^2+<Ca^2+<Fe^3+<Al^3+(filtration resistance mitigation),and the moisture content of recycled filter cake showed a marked decrease.For Ca^2+,Mg^2+,Fe^3+,and Ca^2++Fe^3+,the filtration resistances were almost the same when the total charge concentration was less than 5 mmol·L^–1.However,when the total charge concentration was greater than 5 mmol·L^–1,membrane fouling mitigation increased significantly in the presence of Ca^2+or Fe^3+and remained constant for Mg^2+with the increase of total charge concentration.The filtration resistance mitigation was arranged in the order of Fe^3+>Fe^3++Ca^2+>Ca^2+>Mg^2+.Three mechanisms were proposed in the presence of Fe^3+,such as the decrease of SA concentration,change in p H,and production of hydroxide iron colloids from hydrolysis.The properties of recycled materials(filter cake)were investigated via optical microscope observation,dynamic light scattering,Fourier transform infrared,X-ray photoelectron spectroscopy(XPS),and scanning electron microscopy.The results provide further insight into UF recoveries of alginate extracted from AGS.展开更多
Developing advanced electrode materials is crucial for improving the electrochemical performances of proton batteries.Currently,the anodes are primarily crystalline materials which suffer from inferior cyclic stabilit...Developing advanced electrode materials is crucial for improving the electrochemical performances of proton batteries.Currently,the anodes are primarily crystalline materials which suffer from inferior cyclic stability and high electrode potential.Herein,we propose amorphous electrode materials for proton batteries by using a general ion-exchange protocol to introduce multivalent metal cations for activating the host material.Taking Al^(3+)as an example,theoretical and experimental analysis demonstrates electrostatic interaction between metal cations and lattice oxygen,which is the primary barrier for direct introduction of the multivalent cations,is effectively weakened through ion exchange between Al^(3+)and pre-intercalated K+.The as-prepared Al-MoOx anode therefore delivered a remarkable capacity and outstanding cycling stability that outperforms most of the state-of-the-art counterparts.The assembled full cell also achieved a high voltage of 1.37 V.This work opens up new opportunities for developing high-performance electrodes of proton batteries by introducing amorphous materials.展开更多
基金financial support from the National Natural Science Foundation of China(No.51801078).
文摘To modify the stable thermodynamics and poor kinetics of magnesium hydride(MgH_(2))for solid-state hydrogen storage,MIL-100(Fe)was in situ fabricated on the surfaces of TiO_(2)nano-sheets(NS)by a self-assembly method,and the prepared TiO_(2)NS@MIL-100(Fe)presents an excellent catalytic effect on MgH_(2).The MgH_(2)+7wt.%TiO_(2)NS@MIL-100(Fe)composite can release hydrogen at 200℃,achieving a decrease of 150℃ compared to pure MgH_(2).Besides,the activation energy of dehydrogenation is decreased to 70.62 kJ/mol and 4 wt.%H_(2) can be desorbed within 20 min at a low temperature of 235℃.Under conditions of 100℃ and 3 MPa,MgH_(2)+7wt.%TiO_(2)NS@MIL-100(Fe)absorbs 5 wt.%of H_(2) in 10 min.Surprisingly,6.62 wt.%reversible capacity is maintained after 50 cycles.The modification mechanism is confirmed that the presence of oxygen vacancies and the synergistic effect of multivalent titanium in TiO_(2)NS@MIL-100(Fe)greatly enhance the kinetic and thermodynamic properties of MgH_(2).
基金supports from the National Key R&D Program of China(2020YFA0406204)the National Natural Science Foundation of China(Grant No 51801078).
文摘Catalytic doping of magnesium hydride(MgH_(2))to improve its hydrogen ab/desorption kinetic properties is considered to be an effective and feasible method.In solid-phase catalysis,the extent of contact between the catalyst and the substrate determines the catalytic reaction in a great sense.With large specific surface area and abundant active sites,two-dimensional(2D)nanomaterials are promising catalysts for MgH_(2)via providing numerous pathways for the diffusion and dissociation of hydrogen.In this regard,2D NiMn-based layered double hydroxide and layered metallic oxide(LMO)are designed and introduced into MgH_(2)to improve its hydrogen storage properties.Simultaneous enhancement in interfacial contact,desorption temperature and kinetics are achieved.The MgH_(2)+9wt%Ni3Mn-LMO composites begin to discharge hydrogen at only 190℃and 6.10wt%H_(2)could be charged in 600 s at 150℃.The activation energy for de/hydrogenation is reduced by 42.43%and 46.56%,respectively,compared to pure MgH_(2).Even at a low operating temperature of 235℃,the modified system was still able to release 4.44wt%H_(2)in an hour,which has rarely been reported in previous studies.Microstructure observations and density functional theory calculations revealed that first,the hydrogen pumping effect of Mg_(2)Ni/Mg_(2)NiH_(4) promotes the adsorption and desorption of hydrogen molecules on the surface of MgH_(2),second,MnOx drew electrons from Mg_(2)Ni,producing a new Density of State structure with a lower d-bond center.This unique change further strengthens the Mg_(2)Ni/Mg_(2)NiH_(4) pump effect on MgH_(2).Our work indicates that the application of 2D metal-based catalysts is a feasible and promising approach towards MgH_(2)for solid-state hydrogen storage to meet technical and scientific requirements.
基金supported by the National Natural Science Foundation of China(22075227)the Shaanxi Fundamental Science Research Project for Chemistry and Biology(23JHQ011)。
文摘Na_(3)V_(2)O_(2x)(PO_(4))_(2)F_(3-2x)(NVPOF)is considered one of the most promising cathode materials for sodium-ion batteries due to its favorable working potential and optimal theoretical specific capacity.However,its long-cycle and rate performance are significantly constrained by the low Na^(+)electronic conductivity of NVPOF.Furthermore,the prevalent self-discharge phenomenon restricts its applicability in practical applications.In this paper,the cathode material Na_(3)V_(1.84)Fe_(0.16)(PO_(4))_(2)F_(3)(x=0.16)was synthesized by quantitatively introducing Fe^(3+)into the V-site of NVPOF.The introduction of Fe^(3+)significantly reduced the original bandgap and the energy barrier of NVPOF,as demonstrated through density functional theory calculations(DFT).When material x=0.16 is employed as the cathode material for the sodium-ion battery,the Na^(+)diffusion coefficient is significantly enhanced,exhibiting a lower activation energy of42.93 kJ mol^(-1).Consequently,material x=0.16 exhibits excellent electrochemical performance(rate capacity:57.32 mA h g^(-1)@10 C,cycling capacity:the specific capacity of 101.3 mA h g^(-1)can be stably maintained after 1000 cycles at 1 C current density).It can also achieve a full charge state in only2.39 min at a current density of 10 C while maintaining low energy loss across various stringent self-discharge tests.In addition,the sodium storage mechanism associated with the three-phase transition of Na_(X)V_(1.84)Fe_(0.16)(PO_(4))_(2)F_(3)(X=1,2,3)was elucidated by a series of experiments.In conclusion,this study presents a novel approach to multifunctional advanced sodium-ion battery cathode materials.
基金Supported by Youth Foundation of Education Department in Sichuan Province(07ZB060)Scientific and Technological Supporting Project in Science and Technology Bureau of Sichuan Province(2009SZ0228)~~
文摘A multivalent inactivated Escherichia coli vaccine for forest musk deer by using serotypes O4,O26,and O139 with Al（OH）3 adjuvant was prepared.The vaccine did not cause any adverse reactions in forest musk deer.The immunogenic effects of the vaccine were experimentally investigated in pregnant and young forest musk deer.The serum antibody titers of pregnant and young forest musk deer were determined by performing the micro-agglutination test.The serum antibody titers of pregnant forest musk deer were more stable from 35th to 68th d after the third vaccination,and the serum antibody titers of four pregnant forest musk deer were maintained 25,25,25,and 24 on 68th d after the third vaccination.Young forest musk deer showed serum antibody titers which were obtained due to nursing.Young forest musk deer were administered the first intramuscular vaccine injection at an age of approximately 60 days due to a fall in maternal antibody titers.The serum antibody titers of young forest musk deer were higher after the third vaccination and maintained at approximately the same level until they were 137 days old.The maternal antibodies and the antibodies produced by young forest musk deer could be helpful for protecting the young musk deer from the infections of pathogenic Escherichia coli strains（serotypes O4,O26,and O139）for 137 days after birth（during the nursing period and the period when the forest musk deer were susceptible to diseases）.
文摘In this paper we introduce some new subclesses of meromorphic multivalent functions. Inclusion relations between these classes, the class preserving integral operators and coefficient estimates are obtained.
基金sponsored by the National Natural Science Foundation of China(81672018)the National 13th Five-Year Grand Program on Key Infectious Disease Control(2017ZX10202102)+2 种基金the 13th Five-Year National Science and Technology Major Project for infectious Diseases(2017ZX10305501-002)Shanghai Pujiang Program(19PJ1409100)the Technology Service Platform for Detecting High level Biological Safety Pathogenic Microorganism Supported by Shanghai Science and Technology Commission(18DZ2293000)。
文摘Hand,foot,and mouth disease(HFMD)recently emerged as a global public threat.The licensure of inactivated enterovirus A71(EV-A71)vaccine was the first step in using a vaccine to control HFMD.New challenges arise from changes in the pathogen spectrum while vaccines directed against other common serotypes are in the preclinical stage.The mission of a broad-spectrum prevention strategy clearly favors multivalent vaccines.The development of multivalent vaccines was attempted via the simple combination of potent monovalent vaccines or the construction of chimeric vaccines comprised of epitopes derived from different virus serotypes.The present review summarizes recent advances in HFMD vaccine development and discusses the next steps toward a safe and effective HFMD vaccine that is capable of establishing a crossprotective antibody response.
文摘The constant increase in global energy demand and stricter environmental standards are calling for advanced energy storage technologies that can store electricity from intermittent renewable sources such as wind,solar,and tidal power,to allow the broader implementation of the renewables.The gridoriented sodium-ion batteries,potassium ion batteries and multivalent ion batteries are cheaper and more sustainable alternatives to Li-ion,although they are still in the early stages of development.Additional optimisation of these battery systems is required,to improve the energy and power density,and to solve the safety issues caused by dendrites growth in anodes.Electrolyte,one of the most critical components in these batteries,could significantly influence the electrochemical performances and operations of batteries.In this review,the definitions and influences of three critical components(salts,solvents,and additives)in electrolytes are discussed.The significant advantages,challenges,recent progress and future optimisation directions of various electrolytes for monovalent and multivalent ions batteries(i.e.organic,ionic liquid and aqueous liquid electrolytes,polymer and inorganic solid electrolytes)are summarised to guide the practical application for grid-oriented batteries.
文摘Macroscopic supramolecular assembly(MSA)has been a recent progress in supramolecular chemistry.MSA mainly focuses on studies of the building blocks with a size beyond ten micrometers and the non-covalent interactions between these interactive building blocks to form ordered structures.MSA is essential to realize the concept of"self-assembly at all scales"by bridging most supramolecular researches at molecular level and at macroscopic scale.This review summaries the development of MSA,the basic design principle and related strategies to achieve MSA and potential applications.Correspondingly,we try to elucidate the correlations and differences between"macroscopic assembly"and MSA based on intermolecular interactions;the design principle and the underlying assembly mechanism of MSA are proposed to understand the reported MSA behaviors;to demonstrate further applications of MSA,we introduce some methods to improve the ordered degree of the assembled structures from the point of precise assembly and thus envision some possible fields for the use of MSA.
基金supported by the National Natural Science Foundation of China (Nos. 51871107, 52130101, 51631004)Top-notch Young Talent Program of China (W02070051)+2 种基金Chang Jiang Scholar Program of China (Q2016064)the Program for JLU Science and Technology Innovative Research Team (JLUSTIRT, 2017TD-09)the Fundamental Research Funds for the Central Universities, the Program for Innovative Research Team (in Science and Technology) in University of Jilin Province。
文摘Aqueous multivalent-metal-ion intercalation chemistries hold genuine promise to develop safe and powerful microbatteries for potential use in many miniaturized electronics.However,their development is beset by state-of-the-art electrode materials having practical capacities far below their theoretical values.Here we demonstrate that high compatibility between layered transition-metal oxide hosts and hydrated cation vips substantially boost their multi-electron-redox reactions to offer higher capacities and rate capability,based on typical bipolar vanadium oxides preintercalated with hydrated cations(M_(x)V_(2)O_(5)).When seamlessly integrated on Au current microcollectors with a three-dimensional bicontinuous nanoporous architecture that offers high pathways of electron transfer and ion transport,the constituent Zn_(x)V_(2)O_(5) exhibits specific capacity of as high as∼527 mAh g^(−1) at 5 mV s^(−1) and retains∼300 mAh g^(−1) at 200 mV s^(−1) in 1 M ZnSO_(4) aqueous electrolyte,outperforming the M_(x)V_(2)O_(5)(M=Li,Na,K,Mg).This allows aqueous rechargeable zinc-ion microbatteries constructed with symmetric nanoporous Zn_(x)V_(2)O_(5)/Au interdigital microelectrodes as anode and cathode to show high-density energy of∼358 mWh cm^(−3)(a value that is forty-fold higher than that of 4 V/500μAh Li thin film battery)at high levels of power delivery.
基金supported by the National Natural Science Foundation of China(51822201,52172178,and 21972007).
文摘Flexible aqueous batteries have been thriving with the growing demand for wearable and portable electrical devices.In particular,flexible aqueous mul tivalent ion batteries(FAMIBs),the charge carriers of which include Zn^(2+),Al^(3+),Mg^(2+),and Ca^(2+),have great potential for development owing to their high safety,high elemental abundance in the Earth's crust,and a multi-electron redox mechanism with a high theoretical specific capacity.Therefore,for a comprehensive understanding of this developing field,it is necessary to summarize the recent research progress of FAMIBs in a timely manner.Herein,the advancements of the state-of-the-art FAMIBs are reviewed,and the prospects toward this field are also proposed.This study focuses on the rational material and configuration design for FAMIBs in recent studies to achieve high battery performances under deformation conditions,which is elaborated on by classification of the anode,cathode,hydrogel electrolyte,and configurations of FAMIBs.Besides,the electrochemical performance of FAMIBs under flexible conditions is also reviewed from the perspective of their working voltage,specific capacity,and cycling stability.Finally,the ap proaches to improve the performance of FAMIBs are comprehensively eval uated,followed by the outlook on the challenges and opportunities in future development of FAMIBs.
基金supported by the National Natural Science Foundation of China (22075028)the Beijing Institute of Technology Research Fund Program for Young Scholars (2019CX04092).
文摘Multivalent metal-sulfur(M-S,where M=Mg,Al,Ca,Zn,Fe,etc.)batteries offer unique opportunities to achieve high specific capacity,elemental abundancy and cost-effectiveness beyond lithium-ion batteries(LIBs).However,the slow diffusion of multivalent-metal ions and the shuttle of soluble polysulfide result in impoverished reversible capacity and limited cycle performance of M-S(Mg-S,Al-S,Ca-S,Zn-S,Fe-S,etc.)batteries.It is a necessity to optimize the electrochemical performance,while deepening the understanding of the unique electrochemical reaction mechanism,such as the intrinsic multi-electron reaction process,polysulfides dissoluti on and the in stability of metal an odes.To solve these problems,we have summarized the state-of-the-art progress of current M-S batteries,and sorted out the existing challen ges for different multivalent M-S batteries according to sulfur cathode,electrolytes,metallic an ode and current collectors/separators,respectively.In this literature,we have surveyed and exemplified the strategies developed for better M-S batteries to strengthen the application of green,cost-effective and high energy density M-S batteries.
文摘Multivalent polymer chains exhibit excellent prospect in biomedical applications by serving as therapeutic agents. Using three-dimensional （3D） Langevin dynamics simulations, we investigate adsorption behaviors of multivalent polymer chains to a surface with receptors. Multivalent polymer chains display superselective adsorption. Furthermore, the range of density of surface receptors at which a multivalent polymer chain displays a superselective behavior, narrows down for chains with higher density of ligands. Meanwhile, the optimal density of surface receptors where the highest superselectivity is achieved, decreases with increasing the density of ligands. Then, the conformational properties of bound multivalent chains are studied systematically. Interestingly, we find that the equilibrium radius of gyration Rg and its horizontal component have a maximum as a function of the density of surface receptors. The scaling exponents of Rg with the length of chain suggest that with increasing the density of surface receptors., the conformations of a bound multivalent polymer chain first fall in between those of a two-dimensional （2D） and a 3D chain, while it is slightly collapsed subsequently.
基金the National Natural Science Foundation of Hubei Province(Grant No.2019CFB110)the fund of the Shaanxi Key Laboratory of Fiber Reinforced Light Composite Materials(Grant No.1-KF-2019).
文摘Wearable self-powered systems integrated with energy conversion and storage devices such as solar-charging power units arouse widespread concerns in scientific and industrial realms.However,their applications are hampered by the restrictions of unbefitting size matching between integrated modules,limited tolerance to the variation of input current,reliability,and safety issues.Herein,flexible solar-charging self-powered units based on printed Zn-ion hybrid micro-capacitor as the energy storage module is developed.Unique 3D micro-/nano-architecture of the biomass kelp-carbon combined with multivalent ion(Zn2+)storage endows the aqueous Zn-ion hybrid capacitor with high specific capacity(196.7 mAh g^−1 at 0.1 A g^−1).By employing an in-plane asymmetric printing technique,the fabricated quasi-solid-state Zn-ion hybrid microcapacitors exhibit high rate,long life and energy density up to 8.2μWh cm^−2.After integrating the micro-capacitor with organic solar cells,the derived self-powered system presents outstanding energy conversion/storage efficiency(ηoverall=17.8%),solar-charging cyclic stability(95%after 100 cycles),wide current tolerance,and good mechanical flexibility.Such portable,wearable,and green integrated units offer new insights into design of advanced self-powered systems toward the goal of developing highly safe,economic,stable,and long-life smart wearable electronics.
基金National Research Foundation of Korea,Grant/Award Numbers:NRF-2019R1A2C1084836,NRF-2021R1A4A2001403,NRF-2022R1C1C1011484。
文摘Zinc metal anodes(ZMA)have high theoretical capacities(820 mAh g−1 and 5855 mAh cm−3)and redox potential(−0.76 V vs.standard hydrogen electrode),similar to the electrochemical voltage window of the hydrogen evolution reaction(HER)in a mild acidic electrolyte system,facilitating aqueous zinc batteries competitive in next-generation energy storage devices.However,the HER and byproduct formation effectuated by water-splitting deteriorate the electrochemical performance of ZMA,limiting their application.In this study,a key factor in promoting the HER in carbon-based electrode materials(CEMs),which can provide a larger active surface area and guide uniform zinc metal deposition,was investigated using a series of threedimensional structured templating carbon electrodes(3D-TCEs)with different local graphitic orderings,pore structures,and surface properties.The ultramicropores of CEMs are the determining critical factors in initiating HER and clogging active surfaces by Zn(OH)2 byproduct formation,through a systematic comparative study based on the 3D-TCE series samples.When the 3D-TCEs had a proper graphitic structure with few ultramicropores,they showed highly stable cycling performances over 2000 cycles with average Coulombic efficiencies of≥99%.These results suggest that a well-designed CEM can lead to high-performance ZMA in aqueous zinc batteries.
基金supported by the National Key R&D Program of China(2016YFA0202500)the Natural Science Foundation of China(51803054,51772093)+1 种基金the Natural Science Foundation of Hunan province(2020JJ3022,2019JJ50223,2019JJ20010)the foundation from Education Department of Hunan Province(19B270,SYL201802008)。
文摘In recent years,the pursuit of high-efficiency electrochemical storage technology,the multivalent metalion batteries (MIBs) based on aqueous electrolytes have been widely explored by researchers because of their safety,environmental friendliness,abundant reserves and low price,and especially the merits in energy and power densities.This review firstly expounds on the problems existing in the electrode materials of aqueous multivalent MIBs (Zn^(2+),Mg^(2+),Al^(3+),Ca^(2+)),from the classical inorganic materials to the emerging organic compounds,and then summarizes the design strategies in bulk and interface structure of electrodes with favorable kinetics and stable cycling performance,especially laying the emphasis on the charge storage mechanism of cathode materials and dendrite-free Zinc anode from the aspect of electrolyte optimization strategies,which can be extended to other aqueous multivalent MIBs.Ultimately,the possible development directions of the aqueous multivalent MIBs in the future are provided,anticipating to provide a meaningful guideline for researchers in this area.
文摘In this paper we derive certain sufficient conditions for starlikeness and convexity of order α of meromorphically multivalent functions in the punctured unit disk.
基金National Natural Science Foundation of China(Nos.22131008 and 21971127)the Fundamental Research Funds for the Central Universitiesthe Haihe Laboratory of Sustainable Chemical Transformations for financial support。
文摘In recent years,multicolor cascade supramolecular assemblies with controllable topological morphology have become a research hotspot due to their wide application in light-emitting materials,cell imaging and other fields.Herein,several kinds of macrocycles including cucurbiturils,calixarene and cyclodextrins are used as building blocks to construct fluorescent assemblies with anthryl-conjugated phenylpyridine(G),wherein cucurbit[8]uril(CB[8])and G can form nanowires at a stoichiometric ratio of n:n through host-vip encapsulation to form a non-covalent heterodimer.Significantly,the macrocycle confinement effect drastically enhances the fluorescence emission of G and emission peak generated bathochromic shift from 500 nm to 600 nm.When the supramolecular polymer is further assembled with amphiphilic calix[4]arene(SC_(4)A8),the fluorescence emission of G?CB[8]further increases to 1.4 times,accompanied by the morphological transformation from linear structure to nanorod structure.Subsequently,a very small amount of dye Cy5 is added to the assembly solution as an energy receptor,and the negatively charged G?CB[8]@SC_(4)A8 system is regarded as an energy donor.The efficient energy transfer process enables near-infrared(NIR)emission at 675 nm with 71%energy transfer efficiency(ΦET)at a donor/receptor ratio of 100:1.Finally,the cascade supramolecular assembly has been successfully applied to targeted imaging in the nucleus of HeLa and A549 cancer cells.
基金supported by the Basic Science Research Program through the National Research Foundation of Korea(NRF)Funded by the Ministry of Education(NRF-2019R1A2C1084836,NRF-2018M1A2A2061994,and NRF-2021R1A4A2001403)the KU-KIST School Program。
文摘Rechargeable aluminum batteries(RABs),which use earth-abundant and high-volumetric-capacity metal anodes(8040 m Ah cm-3),have great potential as next-generation power sources because they use cheaper resources to deliver higher energies,compared to current lithium ion batteries.However,the mechanism of charge delivery in the newly developed,ionic liquid-based electrolytic system for RABs differs from that in conventional organic electrolytes.Thus,targeted research efforts are required to address the large overpotentials and cycling decay encountered in the ionic liquid-based electrolytic system.In this study,a nanoporous carbon(NPC)electrode with well-developed nanopores is used to develop a high-performance aluminum anode.The negatively charged nanopores can provide quenched dynamics of electrolyte molecules in the aluminum deposition process,resulting in an increased collision rate.The fast chemical equilibrium of anionic species induced by the facilitated anionic collisions leads to more favorable reduction reactions that form aluminum metals.The nanoconfinement effect causes separated nucleation and growth of aluminum nanoparticles in the multiple confined nanopores,leading to higher coulombic efficiencies and more stable cycling performance compared with macroporous carbon black and 2D stainless steel electrodes.
基金partially supported by the Beijing Outstanding Talents TrainingScience and Technology Programs of the Beijing Municipal Education Commission(SQKM201710016001)+1 种基金the BUCEA Post Graduate Innovation Projectthe Beijing Advanced Innovation Center for Future Urban Design。
文摘Recovery of alginate extracted from aerobic granular sludge(AGS)has given rise to a novel research direction.However,these extracted alginate solutions have a water content of nearly 100%.Alternately,ultrafiltration(UF)is generally used for concentration of polymers.Furthermore,the introduction of multivalent metal ions into alginate may provide a promising method for the development of novel nanomaterials.In this study,membrane fouling mitigation by multivalent metal ions,both individually and in combination,and properties of recycled materials were investigated for UF recovery of sodium alginate(SA).The filtration resistance showed a significantly negative correlation with the concentration of metal ions,arranged in the order of Mg^2+<Ca^2+<Fe^3+<Al^3+(filtration resistance mitigation),and the moisture content of recycled filter cake showed a marked decrease.For Ca^2+,Mg^2+,Fe^3+,and Ca^2++Fe^3+,the filtration resistances were almost the same when the total charge concentration was less than 5 mmol·L^–1.However,when the total charge concentration was greater than 5 mmol·L^–1,membrane fouling mitigation increased significantly in the presence of Ca^2+or Fe^3+and remained constant for Mg^2+with the increase of total charge concentration.The filtration resistance mitigation was arranged in the order of Fe^3+>Fe^3++Ca^2+>Ca^2+>Mg^2+.Three mechanisms were proposed in the presence of Fe^3+,such as the decrease of SA concentration,change in p H,and production of hydroxide iron colloids from hydrolysis.The properties of recycled materials(filter cake)were investigated via optical microscope observation,dynamic light scattering,Fourier transform infrared,X-ray photoelectron spectroscopy(XPS),and scanning electron microscopy.The results provide further insight into UF recoveries of alginate extracted from AGS.
基金supported by the National Natural Science Foundation of China(51904059)Applied Basic Research Program of Liaoning(2022JH2/101300200)+1 种基金Fundamental Research Funds for the Central Universities(N2002005,N2125004,N2225044)Liao Ning Revitalization Talents Program(XLYC1807123).
文摘Developing advanced electrode materials is crucial for improving the electrochemical performances of proton batteries.Currently,the anodes are primarily crystalline materials which suffer from inferior cyclic stability and high electrode potential.Herein,we propose amorphous electrode materials for proton batteries by using a general ion-exchange protocol to introduce multivalent metal cations for activating the host material.Taking Al^(3+)as an example,theoretical and experimental analysis demonstrates electrostatic interaction between metal cations and lattice oxygen,which is the primary barrier for direct introduction of the multivalent cations,is effectively weakened through ion exchange between Al^(3+)and pre-intercalated K+.The as-prepared Al-MoOx anode therefore delivered a remarkable capacity and outstanding cycling stability that outperforms most of the state-of-the-art counterparts.The assembled full cell also achieved a high voltage of 1.37 V.This work opens up new opportunities for developing high-performance electrodes of proton batteries by introducing amorphous materials.
