Microstructure, precipitate and magnetic characteristic of fmal products with different normalizing cooling processes for Fe-3.2%Si low-temperature hot-rolled grain-oriented silicon steel were analyzed and compared wi...Microstructure, precipitate and magnetic characteristic of fmal products with different normalizing cooling processes for Fe-3.2%Si low-temperature hot-rolled grain-oriented silicon steel were analyzed and compared with the hot-rolled plate by optical microscopy (OM), transmission electron microscopy (TEM), and energy dispersive spectrometry (EDS). The results show that, the surface microstructure is uniform, the proportion of recrystallization in matrix increases, and the banding textures are narrowed; the precipitates, whose quantity in normalized plate is more than that in hot-rolled plate greatly, are mainly A1N, MnS, composite precipitates (Cu,Mn)S and so on. Normalizing technology with a temperature of 1120 ℃, holding for 3 min, and a two-stage cooling is a most advantaged method to obtain oriented silicon steel with sharper Goss texture and higher magnetic properties, owing to the uniform surface microstructures and the obvious inhomogeneity of microstructures along the thickness. The normalizing technology with the two-stage cooling is the optimum process, which can generate more fine precipitates dispersed over the matrix, and be beneficial for finished products to get higher magnetic properties.展开更多
Lithium-ion batteries(LIBs),while dominant in energy storage due to high energy density and cycling stability,suffer from severe capacity decay,rate capability degradation,and lithium dendrite formation under low-temp...Lithium-ion batteries(LIBs),while dominant in energy storage due to high energy density and cycling stability,suffer from severe capacity decay,rate capability degradation,and lithium dendrite formation under low-temperature(LT)operation.Therefore,a more comprehensive and systematic understanding of LIB behavior at LT is urgently required.This review article comprehensively reviews recent advancements in electrolyte engineering strategies aimed at improving the low-temperature operational capabilities of LIBs.The study methodically examines critical performance-limiting mechanisms through fundamental analysis of four primary challenges:insufficient ionic conductivity under cryogenic conditions,kinetically hindered charge transfer processes,Li+transport limitations across the solidelectrolyte interphase(SEI),and uncontrolled lithium dendrite growth.The work elaborates on innovative optimization approaches encompassing lithium salt molecular design with tailored dissociation characteristics,solvent matrix optimization through dielectric constant and viscosity regulation,interfacial engineering additives for constructing low-impedance SEI layers,and gel-polymer composite electrolyte systems.Notably,particular emphasis is placed on emerging machine learning-guided electrolyte formulation strategies that enable high-throughput virtual screening of constituent combinations and prediction of structure-property relationships.These artificial intelligence-assisted rational design frameworks demonstrate significant potential for accelerating the development of next-generation LT electrolytes by establishing quantitative composition-performance correlations through advanced data-driven methodologies.展开更多
This study focused on improving the cathode performance of Ba_(0.6)Sr_(0.4)Co_(0.85)Nb_(0.15)O_(3-δ)(BSCN)-based perovskite materials through molybdenum(Mo)doping.Pure BSCN and Mo-modified-BSCN—Ea_(0.6)Sr_(0.4)Co_(0...This study focused on improving the cathode performance of Ba_(0.6)Sr_(0.4)Co_(0.85)Nb_(0.15)O_(3-δ)(BSCN)-based perovskite materials through molybdenum(Mo)doping.Pure BSCN and Mo-modified-BSCN—Ea_(0.6)Sr_(0.4)Co_(0.85)Nb_(0.1)Mo_(0.05)O_(3-δ)(B S CNM_(0.05)),Ba_(0.6)Sr_(0.4)Co_(0.85)Nb_(0.05)Mo_(0.1)O_(3-δ)(BSCNM_(0.1)),and Ba_(0.6)Sr_(0.4)Co_(0.85)Mo_(0.15)O_(3-δ)(BSCM)—with Mo doping contents of 5mol%,10mol%,and15mol%,respectively,were successfully prepared using the sol-gel method.The effects of Mo doping on the crystal structure,conductivity,thermal expansion coefficient,oxygen reduction reaction(ORR)activity,and electrochemical performance were systematically evaluated using X-ray diffraction analysis,thermally induced characterization,electrochemical impedance spectroscopy,and single-cell performance tests.The results revealed that Mo doping could improve the conductivity of the materials,suppress their thermal expansion effects,and significantly improve the electrochemical performance.Surface chemical state analysis using X-ray photoelectron spectroscopy revealed that 5mol%Mo doping could facilitate a high adsorbed oxygen concentration leading to enhanced ORR activity in the materials.Density functional theory calculations confirmed that Mo doping promoted the ORR activity in the materials.At an operating temperature of 600℃,the BSCNM_(0.05)cathode material exhibited significantly enhanced electrochemical impedance characteristics,with a reduced area specific resistance of 0.048Ω·cm~2,which was lower than that of the undoped BSCN matrix material by 32.39%.At the same operating temperature,an anode-supported single cell using a BSCNM_(0.05)cathode achieved a peak power density of 1477 mW·cm^(-2),which was 30.71%,56.30%,and 171.50%higher than those of BSCN,BSCNM_(0.1),and B SCM,respectively.The improved ORR activity and electrochemical performance of BSCNM_(0.05)indicate that it can be used as a cathode material in low-temperature solid oxide fuel cells.展开更多
Low-temperature hydrogenation of silicon tetrachloride(STC)is an essential step in polysilicon production.The addition of CuCl to silicon powder is currently a commonly used catalytic method and the silicon powder act...Low-temperature hydrogenation of silicon tetrachloride(STC)is an essential step in polysilicon production.The addition of CuCl to silicon powder is currently a commonly used catalytic method and the silicon powder acts as both a reactant and a catalyst.However,the reaction mechanism and the structure-activity relationship of this process have not been fully elucidated.In this work,a comprehensive study of the reaction mechanism in the presence of Si and Cu_(3)Si was carried out using density functional theory(DFT)combined with experiments,respectively.The results indicated that the ratedetermining step(RDS)in the presence of Si is the phase transition of Si atom,meanwhile,the RDS in the presence of Cu_(3)Si is the TCS-generation process.The activation barrier of the latter is smaller,highlighting that the interaction of Si with the bulk phase is the pivotal factor influencing the catalytic activity.The feasibility of transition metal doping to facilitate this step was further investigated.The Si disengage energy(E_(d))was used as a quantitative parameter to assess the catalytic activity of the catalysts,and the optimal descriptor was determined through interpretable machine learning.It was demonstrated that d-band center and electron transfer play a crucial role in regulating the level of Ed.This work reveals the mechanism and structure-activity relationship for the low-temperature hydrogenation reaction of STC,and provides a basis for the rational design of catalysts.展开更多
The removal of B and P consumes most of heat energy in Si metallurgical purification process for solar-grade Si. Metal-liquating purification of metallurgical grade silicon (MG-Si), also called Si-recrystallization ...The removal of B and P consumes most of heat energy in Si metallurgical purification process for solar-grade Si. Metal-liquating purification of metallurgical grade silicon (MG-Si), also called Si-recrystallization from metal liquid, was a potential energy-saving method for the removal of B and P efficiently, since Si could be melted at lower temperature by alloying with metal. The selection criteria of metal-liquating system was elaborated, and Al, Sn and In were selected out as the optimum metallic mediums. For Sn-Si system, the segregation coefficient of B decreased to 0.038 at 1 500 K, which was much less than 0.8 at the melting point of Si. The mass fraction of B was diminished from 15×10^-6 to 0.1×10^-6 as MG-Si was purified by twice, while that of most metallic elements could be decreased to 0.1×10^-6 by purifying just once. During the metal-liquating process, the formation of compounds between impurity elements and Si was also an important route of impurity removal. Finally, one low-temperature metallurgical process based on metal-liquating method was proposed.展开更多
Low-temperature slab-reheated grain-oriented silicon steel is characterized by a sharp {411}〈148〉 primary recrystallization texture. To date, the influence of this texture on secondary recrystallization is not clear...Low-temperature slab-reheated grain-oriented silicon steel is characterized by a sharp {411}〈148〉 primary recrystallization texture. To date, the influence of this texture on secondary recrystallization is not clear. Microtextures in primary and secondary reerystallized sheets of low-temperature reheated grain-oriented silicon steel were examined using electron backscatter diffraction. By comparing the textures and microstructures of specific primary reerystallized grains neighboring secondary grains with those of other primary grains, the influences of primary re- crystallization textures and microstructures on the orientations of secondary grains were investigated. Results show that for low-temperature reheated graiworiented silicon steel, the primary recrystallization sheet comprises { 411 } 〈148〉, {111}〈112〉, and {001}〈120〉 texture componems. During secondary recrystallization, the {111}〈112〉 primary recrystallized grains were easily consumed by abnormally grown Goss, deviated Goss, Brass, or {210}〈001〉grains ;the { 411 }〈148〉 primary recrystallized grains were more resistant to being swallowed; and the {001} 〈120 grains were the most resistant to being consumed. For a particular primary grain, the distribution of its surrounding grain boundaries determined how easily it is consumed during secondary recrystallization. Primary grains surrounded by 20°- 45° grain boundaries were consumed much earlier than those having grain boundaries above 45°, which is in accordance with high-energy grain boundary theory. In addition, special ∑9 boundaries between {411}〈148〉 and Goss grains move more slowly than ∑9 boundaries between {111 }〈112〉 and Goss grains, which is attributed to the different positions of 〈110〉 rotation axis with respect to the normals of grain boundaries.展开更多
Mesoporous silicon carbide with high specific surface area was successfully synthesized from an MCM-48/ polyacrylamide nanocomposite precursor in the temperature range of 550-600 ℃ (below the melting point of Mg) b...Mesoporous silicon carbide with high specific surface area was successfully synthesized from an MCM-48/ polyacrylamide nanocomposite precursor in the temperature range of 550-600 ℃ (below the melting point of Mg) by means of a magnesiothermic reduction process. The MCM-48/polyacrylamide precursor nanocomposite was prepared by in-situ polymerization of acrylamide monomer in the presence of mesoporous MCM-48 synthesized by sol-gel method. The physicochemical properties and microstructures of the nanocomposite precursor and the low-temperature SiC product were characterized by X-ray diffraction (XRD), differential scanning calorimetry-thermo gravimetric analysis (DSC-TGA), transmission electron microscopy (TEM) and N2 adsorption-desorption. TEM micrographs and Brunauer-Emmett-Teller (BET) gas adsorption studies showed that the SiC powder was nanocrystalline and had a specific surface area of 330 m2/g and a mesoporosity in the range of 2-10 nm. The presence of an exothermic peak in the DSC trace corresponds to the self-combustion process of the SiC magnesiothermic synthesis. The results also show that the carbon in excess to that required to produce SiC plays a role in the reduction of the SiO2. The mechanism of magnesiothermic synthesis of mesoporous SiC is discussed.展开更多
Lithium-ion batteries are widely recognized as prime candidates for energy storage devices.Ethylene carbonate(EC)has become a critical component in conventional commercial electrolytes due to its exceptional film-form...Lithium-ion batteries are widely recognized as prime candidates for energy storage devices.Ethylene carbonate(EC)has become a critical component in conventional commercial electrolytes due to its exceptional film-forming properties and high dielectric constant.However,the elevated freezing point,high viscosity,and strong solvation energy of EC significantly hinder the transport rate of Li^(+)and the desolvation process at low temperatures.This leads to substantial capacity loss and even lithium plating on graphite anodes.Herein,we have developed an efficient electrolyte system specifically designed for lowtemperature conditions,which consists of 1.0 M lithium bis(fluorosulfonyl)imide(LiFSI)in isoxazole(IZ)with fluorobenzene(FB)as an uncoordinated solvent and fluoroethylene carbonate(FEC)as a filmforming co-solvent.This system effectively lowers the desolvation energy of Li^(+)through dipole-dipole interactions.The weak solvation capability allows more anions to enter the solvation sheath,promoting the formation of contact ion pairs(CIPs)and aggregates(AGGs)that enhance the transport rate of Li^(+)while maintaining high ionic conductivity across a broad temperature range.Moreover,the formation of inorganic-dominant interfacial phases on the graphite anode,induced by fluoroethylene carbonate,significantly enhances the kinetics of Li^(+)transport.At a low temperature of-20℃,this electrolyte system achieves an impressive reversible capacity of 200.9 mAh g^(-1)in graphite half-cell,which is nearly three times that observed with conventional EC-based electrolytes,demonstrating excellent stability throughout its operation.展开更多
To completely recover valuable elements and reduce the amount of waste,the impact of phosphoric acid on the decomposition of rare earth,fluorine and phosphorus during cyclic leaching was studied based on the character...To completely recover valuable elements and reduce the amount of waste,the impact of phosphoric acid on the decomposition of rare earth,fluorine and phosphorus during cyclic leaching was studied based on the characteristics of low-tempe rature sulfuric acid deco mposition.When a single monazite was leached using 75 wt% H_(2)SO_(4) solution with phosphoric acid,the size and number of monazite particles in the washing slag gradually decrease with the increase in phosphoric acid content in the leaching solution.The monazite phase can hardly be found in the slag when the phosphoric acid content reaches 70 g/L,which indicates that phosphoric acid is favorable for monazite decomposition.The mixed rare earth concentrate was leached by 75 wt% H_(2)SO_(4) containing 70 g/L phosphoric acid,the mineral compositions of the washing slag are only gypsum and unwashed rare earth sulfuric acid.After cyclic leaching of75 wt% H_(2)SO_(4),the mineral compositions of the primary leaching washing slag are mainly undecomposed monazite,rare earth sulfate and calcium sulfate.However,monazite is not found in the mineral phase of the second and third leaching washing slag.The leaching rates of rare earth and phosphorus gradually increase with the increase in cyclic leaching times.In addition,the phosphoric acid content in the leaching solution increases with the increase in the number of cyclic leaching time.However,the rising trend decreases when the phosphoric acid content reaches 50 g/L by adsorption and crystallization of phosphoric acid.A small amount of water can be used to clean the leaching residue before washing to recover the more soluble phosphorus acid according to the difference of dissolution between phosphoric acid and rare earth sulfuric acid.展开更多
Aqueous zinc metal batteries(ZMBs)which are environmentally benign and cheap can be used for grid-scale energy storage,but have a short cycling life mainly due to the poor reversibility of zinc metal anodes in mild aq...Aqueous zinc metal batteries(ZMBs)which are environmentally benign and cheap can be used for grid-scale energy storage,but have a short cycling life mainly due to the poor reversibility of zinc metal anodes in mild aqueous electrolytes.A zincophilic carbon(ZC)layer was deposited on a Zn metal foil at 450°C by the up-stream pyrolysis of a hydrogen-bonded supramolecular substance framework,as-sembled from melamine(ME)and cyanuric acid(CA).The zincophilic groups(C=O and C=N)in the ZC layer guide uniform zinc plating/stripping and eliminate dendrites and side reactions.so that assembled symmetrical batteries(ZC@Zn//ZC@Zn)have a long-term service life of 2500 h at 1 mA cm^(−2) and 1 mAh cm^(−2),which is much longer than that of bare Zn anodes(180 h).In addition,ZC@Zn//V2O5 full batteries have a higher capacity of 174 mAh g^(−1) after 1200 cycles at 2 A g^(−1) than a Zn//V_(2)O_(5) counterpart(100 mAh g^(−1)).The strategy developed for the low-temperat-ure deposition of the ZC layer is a new way to construct advanced zinc metal anodes for ZMBs.展开更多
Electrochemical metallurgy at low temperature(<473 K)shows promise for the extraction and refinement of metals and alloys in a green and sustainable manner.However,the kinetics of the electrodeposition process is g...Electrochemical metallurgy at low temperature(<473 K)shows promise for the extraction and refinement of metals and alloys in a green and sustainable manner.However,the kinetics of the electrodeposition process is generally slow at low temperature,resulting in large overpotential and low current efficiency.Thus,the application of external physical fields has emerged as an effective strategy for improving the mass and charge transfer processes during electrochemical reactions.This review highlights the challenges associated with low-temperature electrochemical processes and briefly discusses recent achievements in optimizing electrodeposition processes through the use of external physical fields.The regulating effects on the optimization of the electrodeposition process and the strategies for select-ing various external physical fields,including magnetic,supergravity,and ultrasonic fields are summarized from the perspectives of equipment and mechanisms.Finally,advanced methods for in-situ characterization of external physical field-assisted electrodeposition processes are reviewed to gain a deeper understanding of metallic electrodeposition.An in-depth exploration of the mechanism by which external physical fields affect the electrode process is essential for enhancing the efficiency of metal extraction at low temperatures.展开更多
Maize(Zea mays L.),a globally significant cereal crop,is produced in vast quantities worldwide.However,its growth is severely constrained by low temperatures,particularly during seed germination,which significantly im...Maize(Zea mays L.),a globally significant cereal crop,is produced in vast quantities worldwide.However,its growth is severely constrained by low temperatures,particularly during seed germination,which significantly impairs seedling emergence.In this study,genetic diversity across six germination-associated phenotypic traits(RGR,RSL,RTL,RRSA,RRV,and RSVI)of 304 inbred lines was analyzed,to evaluate the capacity of these lines for low-temperature tolerance.Genome-wide association study(GWAS)was carried out by combining six germination-associated phenotypic traits and genotypic data from 30-fold resequencing.The gene ZmBARK1 was identified through integrated GWAS and RNA-seq analyses,and its association with low-temperature tolerance during maize germination was validated by quantitative real-time PCR(qRT-PCR).ZmBARK1,encoding BRASSINOSTEROID INSENSITIVE 1-associated receptor kinase 1,was located on the bin 4.09 region of maize chromosome 4.Amino acid comparison and subcellular localization analyses revealed that ZmBARK1 is highly homologous to AtBAK1 and is localized to the plasma membrane of the cell,which may be involved in regulating brassinosteroid(BR)signaling.In addition,we revealed the role of ZmBARK1 in low-temperature tolerance during maize germination.Compared with wild-type(WT),the ethyl methanesulfonate(EMS)mutant zmbark1 was characterized by substantially enhanced low-temperature tolerance.Overall,these findings provide promising candidate genes,improve low-temperature tolerance in maize,and advance the understanding of regulatory mechanisms underlying maize's response to low-temperature stress.展开更多
Magnesium alloys are widely used in aerospace and automotive industries due to their lightweight.However,their poor fatigue performance limits the broader application,especially in dynamic stress environments.This stu...Magnesium alloys are widely used in aerospace and automotive industries due to their lightweight.However,their poor fatigue performance limits the broader application,especially in dynamic stress environments.This study explores novel coupled pretreatments of free-end largeangle pre-torsion and low-temperature aging to improve the fatigue resistance of rolled ZK60 magnesium alloy.STA(pre-torsion followed by low-temperature aging)and SAT(low-temperature aging followed by pre-torsion)samples were prepared to investigate the influences of pretreatment coupling sequences.The results of microstructure characterization reveal that pre-torsion significantly enhances the formation of tensile twins and introduces a gradient microstructure with increased dislocation density from the center to the edges.STA process resulted in the highest twinning area fraction of 35.2% and a kernel average misorientation of 0.94 at the edge.Mechanical testing demonstrated that the coupled pre-treatment obtained a better combination of strength and plasticity,significantly improved the yield strength in the compression stage,and increased the tensile-compressive yield ratio to>0.9.In the low-cycle fatigue test,the STA samples exhibited lower cyclic mean stress,a smaller cyclic hardening trend,and better hysteretic symmetry,leading to an improvement in fatigue life of up to 256%.The findings suggest that the combined pre-torsion and low-temperature aging treatments offer a promising approach to enhance the mechanical properties and fatigue resistance of ZK60 magnesium alloy,making it suitable for structural applications in demanding environments.展开更多
Abscisic acid(ABA)plays a key role in promoting the growth and development of plants,as well as mediating the responses of plants to adverse environmental conditions.Here,we measured the photosynthetic capacity of wil...Abscisic acid(ABA)plays a key role in promoting the growth and development of plants,as well as mediating the responses of plants to adverse environmental conditions.Here,we measured the photosynthetic capacity of wild-type RR,mutant sitiens(sit),and ABA-pretreated sit tomato seedlings following exposure to low-temperature(LT)stress.We found that the net photosynthetic rate,intercellular carbon dioxide concentration,transpiration rate,and stomatal conductance of sit seedlings were lower than those of RR seedlings under LT stress.The chloroplast width,area,and number of osmiophilic granules were significantly larger in sit seedlings than in RR seedlings,while the chloroplast length/width ratio was significantly lower in sit seedlings than in RR seedlings.The photochemical activity of sit seedlings was lower,and the expression of photosynthesis-related genes in sit seedlings was altered following exposure to LT stress.ABA pretreatment significantly alleviated the above phenomenon.We also conducted an RNA sequencing analysis and characterized the expression patterns of genes in tomato seedlings following exposure to LT stress.We constructed 15 cDNA libraries and identified several differentially expressed genes involved in photosynthesis,plant hormone signaling transduction,and primary and secondary metabolism.Additional analyses of genes encoding transcription factors and proteins involved in photosynthesis-related processes showed pronounced changes in expression under LT stress.Luciferase reporter assay and electrophoretic mobility shift assay revealed that WRKY22 regulates the expression of PsbA.The PSII of WRKY22 and PsbA-silenced plants was inhibited.Our findings indicate that ABA plays a role in regulating the process of photosynthesis and protecting PSII in tomato under LT stress through the WRKY22-PsbA complex.展开更多
The low-temperature spray drying technology was developed to process instant berry powder with high efficiency and higher anthocyanin retention.The maltodextrin,whey protein and inulin were selected as additives for i...The low-temperature spray drying technology was developed to process instant berry powder with high efficiency and higher anthocyanin retention.The maltodextrin,whey protein and inulin were selected as additives for instant properties formation in berry powder.The effects of inlet air temperature(40℃–80℃),vacuum degree(0.02–0.06 MPa)and additive amount on the physicochemical properties of berry powder were analyzed through solubility,anthocyanin retention and powder yield,based on moisture content and microstructure.The findings indicated that adding maltodextrin to berry enhanced the powder yield and instant solubility.Whey protein,as an additive,provided effective protection for the anthocyanins of berry powder,and the addition less than 10 g·100^(-1) g improved the powder yield.Inulin,as an additive,reduced moisture content of berry powder,which was conducive to the higher anthocyanin retention and solubility.Technique for order preference by similarity to ideal solution(TOPSIS)analysis was conducted to optimize the spray drying parameters for anthocyanin protection and solubility.The addition of 100%maltodextrin enhanced anthocyanin protection and solubility,while maintaining the desired moisture content and powder yield.This approach was used to evaluate the comprehensive quality of berry powder.This research can provide technical guidance for producing berry powder under low-temperature spray drying.展开更多
The occurrence of tetragonal to monoclinic phase(t→m)transformation in zirconia ceramics under humid ambient conditions induces the low-temperature degradation(LTD).Such t→m transformation could be suppressed by gra...The occurrence of tetragonal to monoclinic phase(t→m)transformation in zirconia ceramics under humid ambient conditions induces the low-temperature degradation(LTD).Such t→m transformation could be suppressed by grain size refinement or/and doping small amounts of alumina.Fine-grained dense 3mol%yttria-doped tetragonal zirconia polycrystal(3Y-TZP)ceramics were prepared by pressureless sintering a zirconia powder doped with 0.25wt%alumina.The LTD behaviors of as-prepared 3Y-TZP ceramics were evaluated by accelerated aging at 134℃in water.The samples sintered at 1300℃for 2 h achieve the relative density higher than 99.9%with the average grain size of 147 nm.The 3Y-TZP ceramic exhibits excellent LTD resistance that no t→m transformation takes place after 125 h accelerated aging.Large amounts of defects were observed inside grains evidenced by the high-resolution transmission electron microscopic(HRTEM)analysis.It is proposed that the presence of defects enhances the sintering kinetics and favors the present low-temperature densification.Possible reasons for defects formation were discussed and the mechanical properties of the 3Y-TZP ceramic were reported as well.展开更多
Low-temperature lithium sulfur(Li-S)batteries have attracted increasing attention,but lithium polysulfide(LiPSs)clu stering and tardy ionic mobility have been challenging issues,which could be exacerbated under high s...Low-temperature lithium sulfur(Li-S)batteries have attracted increasing attention,but lithium polysulfide(LiPSs)clu stering and tardy ionic mobility have been challenging issues,which could be exacerbated under high sulfur loading and lean electrolyte.The distinct behaviors of sulfur cathode in lowtemperature Li-S batteries call for special regulations of the sulfur host to improve the electrochemical performances.Here,a three-dimensional Ti_(3)C_(2)micro-cage(TCC)with an interfacial structure modulated by rich curvatures has been fabricated to propel the sulfur electrochemistry at subzero temperatures.Spectroscopic/microscopic analyses and theoretical calculations elucidate that the precipitation of ultrafine Ti-metal particles on the in-situ generated Ti_(3)C_(2)nanoribbons could trigger the self-scrolling of Ti_(3)C_(2)nanoribbons into TCC.Moreover,in-situ ultraviolet-visible spectra collected at low temperature and theoretical calculations verified that the TCC regulated by rich curvatures have effectively alleviated the Li+dissociation barrier,reduced the energy barrier for charge transfer at the electrode-electrolyte interface,and restrained the clustering and shuttling of LiPSs,thus accelerating the electrochemical conversion kinetics of sulfur species at low temperatures.The performances of the carbon-free TCC-S cathode at low temperatures have been also compared from the aspects of cathode configuration and measurement condition,to demonstrate the potential of TCC.This work can not only provide new methodology for regulating the interfacial structure of MXene to enrich the materials library for low-temperature Li-S batteries,but also expand understanding about the role of interfacial structure of sulfur host in Li-S batteries.展开更多
The morphology,crystal structure,and electrochemical performance of spent LiFePO_(4)(S-LFP)are recovered by one-step low-temperature solid phase sintering.After sintering at 550℃ for 3 h,the secondary particle size d...The morphology,crystal structure,and electrochemical performance of spent LiFePO_(4)(S-LFP)are recovered by one-step low-temperature solid phase sintering.After sintering at 550℃ for 3 h,the secondary particle size distribution of regenerated LiFePO4(R-LFP)becomes narrower,and the D_(50) is reduced from 5.6 to 2.3μm.In addition,the content of Li-Fe antisite defect is reduced from 5.73%to 1.20%,and the F is doped to O(2)site in the structure of R-LFP.Moreover,a coating layer comprising carbon and LiF is formed on the surface of R-LFP because of the decomposition of PVDF.Therefore,the R-LFP demonstrates exceptional Li+diffusion dynamics and conductivity,which delivers a high discharge capacity of 157.3 mA·h/g at 0.1C.And it maintains 92%of its initial capacity after 500 cycles at 1C.展开更多
The design and development of high-performance anodes pose significant challenges in the construction of next-generation rechargeable lithium-ion batteries(LIBs).Sodium molybdate dihydrate(Na_(2)MoO_(4)·2H_(2)O)h...The design and development of high-performance anodes pose significant challenges in the construction of next-generation rechargeable lithium-ion batteries(LIBs).Sodium molybdate dihydrate(Na_(2)MoO_(4)·2H_(2)O)has garnered increasing attention due to its cost-effectiveness,non-toxicity and earth abundance.To enhance the Li storage performance of Na_(2)MoO_(4)·2H_(2)O,a crystallographic orientation regulation strategy is proposed in this work.Initially,density functional theory calculations are carried out to demonstrate that the(020)crystal plane of Na_(2)MoO_(4)·2H_(2)O offers the lowest energy barrier for Li^(+)migration.Subsequently,the preferred crystallographic orientation of Na_(2)MoO_(4)·2H_(2)O crystal is tuned through a low-temperature recrystallization method.Furthermore,the microstructure and phase changes of Na_(2)MoO_(4)·2H_(2)O during the lithiation/de-lithiation process are studied using in situ and ex situ XRD tests,ex situ XPS and cyclic voltammetry to unravel its Li^(+)storage mechanism.Upon application as LIBs anode,the Na_(2)MoO_(4)·2H_(2)O single-crystal particles with a preferred(020)surface exhibit superior reversible capacity,high-capacity retention and high cycling stability.The enhanced Li storage performance should be attributed to the regulated crystallographic orientation and small changes in the crystal microstructure during the charge/discharge process,which facilitates Li^(+)migration and bolsters structural stability.Notably,this study introduces a novel concept and a simple synthesis method for the advancement of electrodes in rechargeable batteries.展开更多
The poor oxidation stability of ether-based solvents has long been a major challenge limiting their practical application.To enhance the oxidative stability of ether-based electrolytes,the physicochemical properties o...The poor oxidation stability of ether-based solvents has long been a major challenge limiting their practical application.To enhance the oxidative stability of ether-based electrolytes,the physicochemical properties of various glycol dimethyl ethers are screened,and diglyme(G2)is selected as the sole solvent for the electrolyte.Lithium bis(fluorosulfonyl)imide(LiFSI),a highly dissociative salt,is used as the primary salt;while lithium nitrate(LiNO_(3))and lithium difluorophosphate(LiDFP),which have small ionic sizes and strong binding energies,are added as secondary salts.The resulting electrolyte can modulate the electric double layer structure by NO_(3)^(-) and DFP^(-) on the cathode side,leading to an increased Liþconcentration that is originally repelled by the cathode.Additionally,the oxidation stability of the electrolyte is improved and the formed electrode-electrolyte interphase is more uniform and stable,thereby enhancing the electrochemical performance of the cells.As a result,cells assembled with a total of 1 M ternary lithium salts in G2 solvent can operate at high voltage of 4.4 V.The LijjNCM811 cells maintain 80.2%capacity retention after 270 cycles at room temperature,with an average Coulombic efficiency of 99.5%,and exhibit 88.4%capacity retention after 200 cycles at -30℃.展开更多
基金Projects(51274083,51074062)supported by the National Natural Science Foundation of China
文摘Microstructure, precipitate and magnetic characteristic of fmal products with different normalizing cooling processes for Fe-3.2%Si low-temperature hot-rolled grain-oriented silicon steel were analyzed and compared with the hot-rolled plate by optical microscopy (OM), transmission electron microscopy (TEM), and energy dispersive spectrometry (EDS). The results show that, the surface microstructure is uniform, the proportion of recrystallization in matrix increases, and the banding textures are narrowed; the precipitates, whose quantity in normalized plate is more than that in hot-rolled plate greatly, are mainly A1N, MnS, composite precipitates (Cu,Mn)S and so on. Normalizing technology with a temperature of 1120 ℃, holding for 3 min, and a two-stage cooling is a most advantaged method to obtain oriented silicon steel with sharper Goss texture and higher magnetic properties, owing to the uniform surface microstructures and the obvious inhomogeneity of microstructures along the thickness. The normalizing technology with the two-stage cooling is the optimum process, which can generate more fine precipitates dispersed over the matrix, and be beneficial for finished products to get higher magnetic properties.
基金the financial support from the Key Project of Shaanxi Provincial Natural Science Foundation-Key Project of Laboratory(2025SYS-SYSZD-117)the Natural Science Basic Research Program of Shaanxi(2025JCYBQN-125)+8 种基金Young Talent Fund of Xi'an Association for Science and Technology(0959202513002)the Key Industrial Chain Technology Research Program of Xi'an(24ZDCYJSGG0048)the Key Research and Development Program of Xianyang(L2023-ZDYF-SF-077)Postdoctoral Fellowship Program of CPSF(GZC20241442)Shaanxi Postdoctoral Science Foundation(2024BSHSDZZ070)Research Funds for the Interdisciplinary Projects,CHU(300104240913)the Fundamental Research Funds for the Central Universities,CHU(300102385739,300102384201,300102384103)the Scientific Innovation Practice Project of Postgraduate of Chang'an University(300103725063)the financial support from the Australian Research Council。
文摘Lithium-ion batteries(LIBs),while dominant in energy storage due to high energy density and cycling stability,suffer from severe capacity decay,rate capability degradation,and lithium dendrite formation under low-temperature(LT)operation.Therefore,a more comprehensive and systematic understanding of LIB behavior at LT is urgently required.This review article comprehensively reviews recent advancements in electrolyte engineering strategies aimed at improving the low-temperature operational capabilities of LIBs.The study methodically examines critical performance-limiting mechanisms through fundamental analysis of four primary challenges:insufficient ionic conductivity under cryogenic conditions,kinetically hindered charge transfer processes,Li+transport limitations across the solidelectrolyte interphase(SEI),and uncontrolled lithium dendrite growth.The work elaborates on innovative optimization approaches encompassing lithium salt molecular design with tailored dissociation characteristics,solvent matrix optimization through dielectric constant and viscosity regulation,interfacial engineering additives for constructing low-impedance SEI layers,and gel-polymer composite electrolyte systems.Notably,particular emphasis is placed on emerging machine learning-guided electrolyte formulation strategies that enable high-throughput virtual screening of constituent combinations and prediction of structure-property relationships.These artificial intelligence-assisted rational design frameworks demonstrate significant potential for accelerating the development of next-generation LT electrolytes by establishing quantitative composition-performance correlations through advanced data-driven methodologies.
基金financially supported by the National Natural Science Foundation of China(No.22309067)the Open Project Program of the State Key Laboratory of Materials-Oriented Chemical Engineering,China(No.KL21-05)the Marine Equipment and Technology Institute,Jiangsu University of Science and Technology,China(No.XTCX202404)。
文摘This study focused on improving the cathode performance of Ba_(0.6)Sr_(0.4)Co_(0.85)Nb_(0.15)O_(3-δ)(BSCN)-based perovskite materials through molybdenum(Mo)doping.Pure BSCN and Mo-modified-BSCN—Ea_(0.6)Sr_(0.4)Co_(0.85)Nb_(0.1)Mo_(0.05)O_(3-δ)(B S CNM_(0.05)),Ba_(0.6)Sr_(0.4)Co_(0.85)Nb_(0.05)Mo_(0.1)O_(3-δ)(BSCNM_(0.1)),and Ba_(0.6)Sr_(0.4)Co_(0.85)Mo_(0.15)O_(3-δ)(BSCM)—with Mo doping contents of 5mol%,10mol%,and15mol%,respectively,were successfully prepared using the sol-gel method.The effects of Mo doping on the crystal structure,conductivity,thermal expansion coefficient,oxygen reduction reaction(ORR)activity,and electrochemical performance were systematically evaluated using X-ray diffraction analysis,thermally induced characterization,electrochemical impedance spectroscopy,and single-cell performance tests.The results revealed that Mo doping could improve the conductivity of the materials,suppress their thermal expansion effects,and significantly improve the electrochemical performance.Surface chemical state analysis using X-ray photoelectron spectroscopy revealed that 5mol%Mo doping could facilitate a high adsorbed oxygen concentration leading to enhanced ORR activity in the materials.Density functional theory calculations confirmed that Mo doping promoted the ORR activity in the materials.At an operating temperature of 600℃,the BSCNM_(0.05)cathode material exhibited significantly enhanced electrochemical impedance characteristics,with a reduced area specific resistance of 0.048Ω·cm~2,which was lower than that of the undoped BSCN matrix material by 32.39%.At the same operating temperature,an anode-supported single cell using a BSCNM_(0.05)cathode achieved a peak power density of 1477 mW·cm^(-2),which was 30.71%,56.30%,and 171.50%higher than those of BSCN,BSCNM_(0.1),and B SCM,respectively.The improved ORR activity and electrochemical performance of BSCNM_(0.05)indicate that it can be used as a cathode material in low-temperature solid oxide fuel cells.
基金supported by Hubei Three Gorges Laboratory Open Innovation Fund Project(SC231002)CFD Simulation to Explore the Mass and Heat Transfer Laws of Thermal Decomposition of Mixed Salt Organic Compounds Project(2021YFC 3201404).
文摘Low-temperature hydrogenation of silicon tetrachloride(STC)is an essential step in polysilicon production.The addition of CuCl to silicon powder is currently a commonly used catalytic method and the silicon powder acts as both a reactant and a catalyst.However,the reaction mechanism and the structure-activity relationship of this process have not been fully elucidated.In this work,a comprehensive study of the reaction mechanism in the presence of Si and Cu_(3)Si was carried out using density functional theory(DFT)combined with experiments,respectively.The results indicated that the ratedetermining step(RDS)in the presence of Si is the phase transition of Si atom,meanwhile,the RDS in the presence of Cu_(3)Si is the TCS-generation process.The activation barrier of the latter is smaller,highlighting that the interaction of Si with the bulk phase is the pivotal factor influencing the catalytic activity.The feasibility of transition metal doping to facilitate this step was further investigated.The Si disengage energy(E_(d))was used as a quantitative parameter to assess the catalytic activity of the catalysts,and the optimal descriptor was determined through interpretable machine learning.It was demonstrated that d-band center and electron transfer play a crucial role in regulating the level of Ed.This work reveals the mechanism and structure-activity relationship for the low-temperature hydrogenation reaction of STC,and provides a basis for the rational design of catalysts.
基金Project (2009BAB49B04) supported by National Key Technologies R&D Program, China
文摘The removal of B and P consumes most of heat energy in Si metallurgical purification process for solar-grade Si. Metal-liquating purification of metallurgical grade silicon (MG-Si), also called Si-recrystallization from metal liquid, was a potential energy-saving method for the removal of B and P efficiently, since Si could be melted at lower temperature by alloying with metal. The selection criteria of metal-liquating system was elaborated, and Al, Sn and In were selected out as the optimum metallic mediums. For Sn-Si system, the segregation coefficient of B decreased to 0.038 at 1 500 K, which was much less than 0.8 at the melting point of Si. The mass fraction of B was diminished from 15×10^-6 to 0.1×10^-6 as MG-Si was purified by twice, while that of most metallic elements could be decreased to 0.1×10^-6 by purifying just once. During the metal-liquating process, the formation of compounds between impurity elements and Si was also an important route of impurity removal. Finally, one low-temperature metallurgical process based on metal-liquating method was proposed.
基金Item Sponsored by National High Technology Research and Development Program of China(2012AA03A505)
文摘Low-temperature slab-reheated grain-oriented silicon steel is characterized by a sharp {411}〈148〉 primary recrystallization texture. To date, the influence of this texture on secondary recrystallization is not clear. Microtextures in primary and secondary reerystallized sheets of low-temperature reheated grain-oriented silicon steel were examined using electron backscatter diffraction. By comparing the textures and microstructures of specific primary reerystallized grains neighboring secondary grains with those of other primary grains, the influences of primary re- crystallization textures and microstructures on the orientations of secondary grains were investigated. Results show that for low-temperature reheated graiworiented silicon steel, the primary recrystallization sheet comprises { 411 } 〈148〉, {111}〈112〉, and {001}〈120〉 texture componems. During secondary recrystallization, the {111}〈112〉 primary recrystallized grains were easily consumed by abnormally grown Goss, deviated Goss, Brass, or {210}〈001〉grains ;the { 411 }〈148〉 primary recrystallized grains were more resistant to being swallowed; and the {001} 〈120 grains were the most resistant to being consumed. For a particular primary grain, the distribution of its surrounding grain boundaries determined how easily it is consumed during secondary recrystallization. Primary grains surrounded by 20°- 45° grain boundaries were consumed much earlier than those having grain boundaries above 45°, which is in accordance with high-energy grain boundary theory. In addition, special ∑9 boundaries between {411}〈148〉 and Goss grains move more slowly than ∑9 boundaries between {111 }〈112〉 and Goss grains, which is attributed to the different positions of 〈110〉 rotation axis with respect to the normals of grain boundaries.
文摘Mesoporous silicon carbide with high specific surface area was successfully synthesized from an MCM-48/ polyacrylamide nanocomposite precursor in the temperature range of 550-600 ℃ (below the melting point of Mg) by means of a magnesiothermic reduction process. The MCM-48/polyacrylamide precursor nanocomposite was prepared by in-situ polymerization of acrylamide monomer in the presence of mesoporous MCM-48 synthesized by sol-gel method. The physicochemical properties and microstructures of the nanocomposite precursor and the low-temperature SiC product were characterized by X-ray diffraction (XRD), differential scanning calorimetry-thermo gravimetric analysis (DSC-TGA), transmission electron microscopy (TEM) and N2 adsorption-desorption. TEM micrographs and Brunauer-Emmett-Teller (BET) gas adsorption studies showed that the SiC powder was nanocrystalline and had a specific surface area of 330 m2/g and a mesoporosity in the range of 2-10 nm. The presence of an exothermic peak in the DSC trace corresponds to the self-combustion process of the SiC magnesiothermic synthesis. The results also show that the carbon in excess to that required to produce SiC plays a role in the reduction of the SiO2. The mechanism of magnesiothermic synthesis of mesoporous SiC is discussed.
基金financial support from the Department of Science and Technology of Jilin Province(20240304104SF,20240304103SF)the Research and Innovation Fund of the Beihua University for the Graduate Student(Major Project 2023012)。
文摘Lithium-ion batteries are widely recognized as prime candidates for energy storage devices.Ethylene carbonate(EC)has become a critical component in conventional commercial electrolytes due to its exceptional film-forming properties and high dielectric constant.However,the elevated freezing point,high viscosity,and strong solvation energy of EC significantly hinder the transport rate of Li^(+)and the desolvation process at low temperatures.This leads to substantial capacity loss and even lithium plating on graphite anodes.Herein,we have developed an efficient electrolyte system specifically designed for lowtemperature conditions,which consists of 1.0 M lithium bis(fluorosulfonyl)imide(LiFSI)in isoxazole(IZ)with fluorobenzene(FB)as an uncoordinated solvent and fluoroethylene carbonate(FEC)as a filmforming co-solvent.This system effectively lowers the desolvation energy of Li^(+)through dipole-dipole interactions.The weak solvation capability allows more anions to enter the solvation sheath,promoting the formation of contact ion pairs(CIPs)and aggregates(AGGs)that enhance the transport rate of Li^(+)while maintaining high ionic conductivity across a broad temperature range.Moreover,the formation of inorganic-dominant interfacial phases on the graphite anode,induced by fluoroethylene carbonate,significantly enhances the kinetics of Li^(+)transport.At a low temperature of-20℃,this electrolyte system achieves an impressive reversible capacity of 200.9 mAh g^(-1)in graphite half-cell,which is nearly three times that observed with conventional EC-based electrolytes,demonstrating excellent stability throughout its operation.
基金support by the National Natural Science Foundation of Inner Mongolia (2022SHZR1885)Natural Science Foundation of Hebei province (E2022402101,E2022402105)。
文摘To completely recover valuable elements and reduce the amount of waste,the impact of phosphoric acid on the decomposition of rare earth,fluorine and phosphorus during cyclic leaching was studied based on the characteristics of low-tempe rature sulfuric acid deco mposition.When a single monazite was leached using 75 wt% H_(2)SO_(4) solution with phosphoric acid,the size and number of monazite particles in the washing slag gradually decrease with the increase in phosphoric acid content in the leaching solution.The monazite phase can hardly be found in the slag when the phosphoric acid content reaches 70 g/L,which indicates that phosphoric acid is favorable for monazite decomposition.The mixed rare earth concentrate was leached by 75 wt% H_(2)SO_(4) containing 70 g/L phosphoric acid,the mineral compositions of the washing slag are only gypsum and unwashed rare earth sulfuric acid.After cyclic leaching of75 wt% H_(2)SO_(4),the mineral compositions of the primary leaching washing slag are mainly undecomposed monazite,rare earth sulfate and calcium sulfate.However,monazite is not found in the mineral phase of the second and third leaching washing slag.The leaching rates of rare earth and phosphorus gradually increase with the increase in cyclic leaching times.In addition,the phosphoric acid content in the leaching solution increases with the increase in the number of cyclic leaching time.However,the rising trend decreases when the phosphoric acid content reaches 50 g/L by adsorption and crystallization of phosphoric acid.A small amount of water can be used to clean the leaching residue before washing to recover the more soluble phosphorus acid according to the difference of dissolution between phosphoric acid and rare earth sulfuric acid.
基金partially supported by the National Natural Science Foundation of China(22479022)Liaoning Revitalization Talents Program(XLYC2007129)。
文摘Aqueous zinc metal batteries(ZMBs)which are environmentally benign and cheap can be used for grid-scale energy storage,but have a short cycling life mainly due to the poor reversibility of zinc metal anodes in mild aqueous electrolytes.A zincophilic carbon(ZC)layer was deposited on a Zn metal foil at 450°C by the up-stream pyrolysis of a hydrogen-bonded supramolecular substance framework,as-sembled from melamine(ME)and cyanuric acid(CA).The zincophilic groups(C=O and C=N)in the ZC layer guide uniform zinc plating/stripping and eliminate dendrites and side reactions.so that assembled symmetrical batteries(ZC@Zn//ZC@Zn)have a long-term service life of 2500 h at 1 mA cm^(−2) and 1 mAh cm^(−2),which is much longer than that of bare Zn anodes(180 h).In addition,ZC@Zn//V2O5 full batteries have a higher capacity of 174 mAh g^(−1) after 1200 cycles at 2 A g^(−1) than a Zn//V_(2)O_(5) counterpart(100 mAh g^(−1)).The strategy developed for the low-temperat-ure deposition of the ZC layer is a new way to construct advanced zinc metal anodes for ZMBs.
基金supported by Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai)(No.SML2023SP243)the National Key Research and Development Program of China(No.2022YFC2906100)the National Natural Science Foundation of China(No.92475202)are acknowledged.
文摘Electrochemical metallurgy at low temperature(<473 K)shows promise for the extraction and refinement of metals and alloys in a green and sustainable manner.However,the kinetics of the electrodeposition process is generally slow at low temperature,resulting in large overpotential and low current efficiency.Thus,the application of external physical fields has emerged as an effective strategy for improving the mass and charge transfer processes during electrochemical reactions.This review highlights the challenges associated with low-temperature electrochemical processes and briefly discusses recent achievements in optimizing electrodeposition processes through the use of external physical fields.The regulating effects on the optimization of the electrodeposition process and the strategies for select-ing various external physical fields,including magnetic,supergravity,and ultrasonic fields are summarized from the perspectives of equipment and mechanisms.Finally,advanced methods for in-situ characterization of external physical field-assisted electrodeposition processes are reviewed to gain a deeper understanding of metallic electrodeposition.An in-depth exploration of the mechanism by which external physical fields affect the electrode process is essential for enhancing the efficiency of metal extraction at low temperatures.
基金supported by the Key Research and Development Project of Heilongjiang Province(2022ZX02B01)the Natural Science Foundation Project of Heilongjiang Province(YQ2022C009)the Natural Science Foundation of Shandong Province(K22LB56)。
文摘Maize(Zea mays L.),a globally significant cereal crop,is produced in vast quantities worldwide.However,its growth is severely constrained by low temperatures,particularly during seed germination,which significantly impairs seedling emergence.In this study,genetic diversity across six germination-associated phenotypic traits(RGR,RSL,RTL,RRSA,RRV,and RSVI)of 304 inbred lines was analyzed,to evaluate the capacity of these lines for low-temperature tolerance.Genome-wide association study(GWAS)was carried out by combining six germination-associated phenotypic traits and genotypic data from 30-fold resequencing.The gene ZmBARK1 was identified through integrated GWAS and RNA-seq analyses,and its association with low-temperature tolerance during maize germination was validated by quantitative real-time PCR(qRT-PCR).ZmBARK1,encoding BRASSINOSTEROID INSENSITIVE 1-associated receptor kinase 1,was located on the bin 4.09 region of maize chromosome 4.Amino acid comparison and subcellular localization analyses revealed that ZmBARK1 is highly homologous to AtBAK1 and is localized to the plasma membrane of the cell,which may be involved in regulating brassinosteroid(BR)signaling.In addition,we revealed the role of ZmBARK1 in low-temperature tolerance during maize germination.Compared with wild-type(WT),the ethyl methanesulfonate(EMS)mutant zmbark1 was characterized by substantially enhanced low-temperature tolerance.Overall,these findings provide promising candidate genes,improve low-temperature tolerance in maize,and advance the understanding of regulatory mechanisms underlying maize's response to low-temperature stress.
基金sponsored by the National Natural Science Foundation of China(Nos.52175143,and 51571150).
文摘Magnesium alloys are widely used in aerospace and automotive industries due to their lightweight.However,their poor fatigue performance limits the broader application,especially in dynamic stress environments.This study explores novel coupled pretreatments of free-end largeangle pre-torsion and low-temperature aging to improve the fatigue resistance of rolled ZK60 magnesium alloy.STA(pre-torsion followed by low-temperature aging)and SAT(low-temperature aging followed by pre-torsion)samples were prepared to investigate the influences of pretreatment coupling sequences.The results of microstructure characterization reveal that pre-torsion significantly enhances the formation of tensile twins and introduces a gradient microstructure with increased dislocation density from the center to the edges.STA process resulted in the highest twinning area fraction of 35.2% and a kernel average misorientation of 0.94 at the edge.Mechanical testing demonstrated that the coupled pre-treatment obtained a better combination of strength and plasticity,significantly improved the yield strength in the compression stage,and increased the tensile-compressive yield ratio to>0.9.In the low-cycle fatigue test,the STA samples exhibited lower cyclic mean stress,a smaller cyclic hardening trend,and better hysteretic symmetry,leading to an improvement in fatigue life of up to 256%.The findings suggest that the combined pre-torsion and low-temperature aging treatments offer a promising approach to enhance the mechanical properties and fatigue resistance of ZK60 magnesium alloy,making it suitable for structural applications in demanding environments.
基金supported by the National Natural Science Foundation of China(32272791 and 32072651)the earmarked fund for CARS(CARS-23)+1 种基金the Joint Fund for Innovation Enhancement of Liaoning Province,China(2021-NLTS-11-01)the support program for Young and Middle-aged Scientific and Technological Innovation Talents,China(RC210293)。
文摘Abscisic acid(ABA)plays a key role in promoting the growth and development of plants,as well as mediating the responses of plants to adverse environmental conditions.Here,we measured the photosynthetic capacity of wild-type RR,mutant sitiens(sit),and ABA-pretreated sit tomato seedlings following exposure to low-temperature(LT)stress.We found that the net photosynthetic rate,intercellular carbon dioxide concentration,transpiration rate,and stomatal conductance of sit seedlings were lower than those of RR seedlings under LT stress.The chloroplast width,area,and number of osmiophilic granules were significantly larger in sit seedlings than in RR seedlings,while the chloroplast length/width ratio was significantly lower in sit seedlings than in RR seedlings.The photochemical activity of sit seedlings was lower,and the expression of photosynthesis-related genes in sit seedlings was altered following exposure to LT stress.ABA pretreatment significantly alleviated the above phenomenon.We also conducted an RNA sequencing analysis and characterized the expression patterns of genes in tomato seedlings following exposure to LT stress.We constructed 15 cDNA libraries and identified several differentially expressed genes involved in photosynthesis,plant hormone signaling transduction,and primary and secondary metabolism.Additional analyses of genes encoding transcription factors and proteins involved in photosynthesis-related processes showed pronounced changes in expression under LT stress.Luciferase reporter assay and electrophoretic mobility shift assay revealed that WRKY22 regulates the expression of PsbA.The PSII of WRKY22 and PsbA-silenced plants was inhibited.Our findings indicate that ABA plays a role in regulating the process of photosynthesis and protecting PSII in tomato under LT stress through the WRKY22-PsbA complex.
基金Supported by the National Natural Science Foundation of China(32072352)。
文摘The low-temperature spray drying technology was developed to process instant berry powder with high efficiency and higher anthocyanin retention.The maltodextrin,whey protein and inulin were selected as additives for instant properties formation in berry powder.The effects of inlet air temperature(40℃–80℃),vacuum degree(0.02–0.06 MPa)and additive amount on the physicochemical properties of berry powder were analyzed through solubility,anthocyanin retention and powder yield,based on moisture content and microstructure.The findings indicated that adding maltodextrin to berry enhanced the powder yield and instant solubility.Whey protein,as an additive,provided effective protection for the anthocyanins of berry powder,and the addition less than 10 g·100^(-1) g improved the powder yield.Inulin,as an additive,reduced moisture content of berry powder,which was conducive to the higher anthocyanin retention and solubility.Technique for order preference by similarity to ideal solution(TOPSIS)analysis was conducted to optimize the spray drying parameters for anthocyanin protection and solubility.The addition of 100%maltodextrin enhanced anthocyanin protection and solubility,while maintaining the desired moisture content and powder yield.This approach was used to evaluate the comprehensive quality of berry powder.This research can provide technical guidance for producing berry powder under low-temperature spray drying.
基金financially supported by the Foundation of Hubei Province Key Laboratory of Green Materials for Light Industry,Hubei University of Technology。
文摘The occurrence of tetragonal to monoclinic phase(t→m)transformation in zirconia ceramics under humid ambient conditions induces the low-temperature degradation(LTD).Such t→m transformation could be suppressed by grain size refinement or/and doping small amounts of alumina.Fine-grained dense 3mol%yttria-doped tetragonal zirconia polycrystal(3Y-TZP)ceramics were prepared by pressureless sintering a zirconia powder doped with 0.25wt%alumina.The LTD behaviors of as-prepared 3Y-TZP ceramics were evaluated by accelerated aging at 134℃in water.The samples sintered at 1300℃for 2 h achieve the relative density higher than 99.9%with the average grain size of 147 nm.The 3Y-TZP ceramic exhibits excellent LTD resistance that no t→m transformation takes place after 125 h accelerated aging.Large amounts of defects were observed inside grains evidenced by the high-resolution transmission electron microscopic(HRTEM)analysis.It is proposed that the presence of defects enhances the sintering kinetics and favors the present low-temperature densification.Possible reasons for defects formation were discussed and the mechanical properties of the 3Y-TZP ceramic were reported as well.
基金support from the National Natural Science Foundation of China for financial support(22175054)the Distinguished Project for Scientific Research in Universities of Anhui Province(2024AH020011)+2 种基金the Key Project for Cultivation of Outstanding Young Scholars in Universities of Anhui Province(YQZD2024015)the Key Project of Provincial Natural Science Research Foundation of Anhui Universities,China(No.2022AH050406)the Anhui Province Research Funding for Outstanding Young Talents in Colleges and Universities,China(No.gxyq2022021)。
文摘Low-temperature lithium sulfur(Li-S)batteries have attracted increasing attention,but lithium polysulfide(LiPSs)clu stering and tardy ionic mobility have been challenging issues,which could be exacerbated under high sulfur loading and lean electrolyte.The distinct behaviors of sulfur cathode in lowtemperature Li-S batteries call for special regulations of the sulfur host to improve the electrochemical performances.Here,a three-dimensional Ti_(3)C_(2)micro-cage(TCC)with an interfacial structure modulated by rich curvatures has been fabricated to propel the sulfur electrochemistry at subzero temperatures.Spectroscopic/microscopic analyses and theoretical calculations elucidate that the precipitation of ultrafine Ti-metal particles on the in-situ generated Ti_(3)C_(2)nanoribbons could trigger the self-scrolling of Ti_(3)C_(2)nanoribbons into TCC.Moreover,in-situ ultraviolet-visible spectra collected at low temperature and theoretical calculations verified that the TCC regulated by rich curvatures have effectively alleviated the Li+dissociation barrier,reduced the energy barrier for charge transfer at the electrode-electrolyte interface,and restrained the clustering and shuttling of LiPSs,thus accelerating the electrochemical conversion kinetics of sulfur species at low temperatures.The performances of the carbon-free TCC-S cathode at low temperatures have been also compared from the aspects of cathode configuration and measurement condition,to demonstrate the potential of TCC.This work can not only provide new methodology for regulating the interfacial structure of MXene to enrich the materials library for low-temperature Li-S batteries,but also expand understanding about the role of interfacial structure of sulfur host in Li-S batteries.
基金supported by the National Natural Science Foundation of China(Nos.51874360,51974370,52074360,52122407,52174285)the Innovation and Entrepreneurship Project of Hunan Province,China(No.2020GK4051)+1 种基金the Key R&D Program of Yunan Province,China(No.202103AA080019)the Natural Science Foundation for Distinguished Young Scholars of Hunan Province,China(No.2024JJ2077)。
文摘The morphology,crystal structure,and electrochemical performance of spent LiFePO_(4)(S-LFP)are recovered by one-step low-temperature solid phase sintering.After sintering at 550℃ for 3 h,the secondary particle size distribution of regenerated LiFePO4(R-LFP)becomes narrower,and the D_(50) is reduced from 5.6 to 2.3μm.In addition,the content of Li-Fe antisite defect is reduced from 5.73%to 1.20%,and the F is doped to O(2)site in the structure of R-LFP.Moreover,a coating layer comprising carbon and LiF is formed on the surface of R-LFP because of the decomposition of PVDF.Therefore,the R-LFP demonstrates exceptional Li+diffusion dynamics and conductivity,which delivers a high discharge capacity of 157.3 mA·h/g at 0.1C.And it maintains 92%of its initial capacity after 500 cycles at 1C.
基金supported by the Natural Science Foundation of Guizhou Province(No.ZK 2022-044)the Platform of Science and Technology and Talent Team Plan of Guizhou Province(No.GCC[2023]007)+1 种基金the National Science Foundation of China(Nos.52101010 and 11964006)the Fund of Natural Science Special(Special Post)Research Foundation of Guizhou University(No.2021-018).
文摘The design and development of high-performance anodes pose significant challenges in the construction of next-generation rechargeable lithium-ion batteries(LIBs).Sodium molybdate dihydrate(Na_(2)MoO_(4)·2H_(2)O)has garnered increasing attention due to its cost-effectiveness,non-toxicity and earth abundance.To enhance the Li storage performance of Na_(2)MoO_(4)·2H_(2)O,a crystallographic orientation regulation strategy is proposed in this work.Initially,density functional theory calculations are carried out to demonstrate that the(020)crystal plane of Na_(2)MoO_(4)·2H_(2)O offers the lowest energy barrier for Li^(+)migration.Subsequently,the preferred crystallographic orientation of Na_(2)MoO_(4)·2H_(2)O crystal is tuned through a low-temperature recrystallization method.Furthermore,the microstructure and phase changes of Na_(2)MoO_(4)·2H_(2)O during the lithiation/de-lithiation process are studied using in situ and ex situ XRD tests,ex situ XPS and cyclic voltammetry to unravel its Li^(+)storage mechanism.Upon application as LIBs anode,the Na_(2)MoO_(4)·2H_(2)O single-crystal particles with a preferred(020)surface exhibit superior reversible capacity,high-capacity retention and high cycling stability.The enhanced Li storage performance should be attributed to the regulated crystallographic orientation and small changes in the crystal microstructure during the charge/discharge process,which facilitates Li^(+)migration and bolsters structural stability.Notably,this study introduces a novel concept and a simple synthesis method for the advancement of electrodes in rechargeable batteries.
文摘The poor oxidation stability of ether-based solvents has long been a major challenge limiting their practical application.To enhance the oxidative stability of ether-based electrolytes,the physicochemical properties of various glycol dimethyl ethers are screened,and diglyme(G2)is selected as the sole solvent for the electrolyte.Lithium bis(fluorosulfonyl)imide(LiFSI),a highly dissociative salt,is used as the primary salt;while lithium nitrate(LiNO_(3))and lithium difluorophosphate(LiDFP),which have small ionic sizes and strong binding energies,are added as secondary salts.The resulting electrolyte can modulate the electric double layer structure by NO_(3)^(-) and DFP^(-) on the cathode side,leading to an increased Liþconcentration that is originally repelled by the cathode.Additionally,the oxidation stability of the electrolyte is improved and the formed electrode-electrolyte interphase is more uniform and stable,thereby enhancing the electrochemical performance of the cells.As a result,cells assembled with a total of 1 M ternary lithium salts in G2 solvent can operate at high voltage of 4.4 V.The LijjNCM811 cells maintain 80.2%capacity retention after 270 cycles at room temperature,with an average Coulombic efficiency of 99.5%,and exhibit 88.4%capacity retention after 200 cycles at -30℃.