The rapid advancement of modern science and technology,coupled with the recent surge in new-energy electric vehicles,has significantly boosted the demand for lithium.This has promoted the development and efficient uti...The rapid advancement of modern science and technology,coupled with the recent surge in new-energy electric vehicles,has significantly boosted the demand for lithium.This has promoted the development and efficient utilization of lepidolite as a lithium source.Therefore,the processes for the flotation of lepidolite have been studied in depth,particularly the development and use of lepidolite flotation collectors and the action mechanism of the collectors on the lepidolite surface.Based on the crystal-structure characteristics of lepidolite minerals,this review focuses on the application of anionic collectors,amine cationic collectors(primary amines,quaternary ammonium salts,ether amines,and Gemini amines),and combined collectors to the flotation behavior of lepidolite as well as the adsorption mechanisms.New directions and technologies for the controllable flotation of lepidolite are proposed,including process improvement,reagent synthesis,and mechanistic research.This analysis demonstrates the need for the further study of the complex environment inside lepidolite and pulp.By using modern analytical detection methods and quantum chemical calculations,research on reagents for the flotation of lepidolite has expanded,providing new concepts and references for the efficient flotation recovery and utilization of lepidolite.展开更多
In recent years, the research advancements have high-lighted the critical role of the A-site cation in determining the optoelectronic and physicochemical properties of organicinorganic lead halide perovskites. Mixed-c...In recent years, the research advancements have high-lighted the critical role of the A-site cation in determining the optoelectronic and physicochemical properties of organicinorganic lead halide perovskites. Mixed-cation perovskites(MCPs) have been extensively used as absorber thin films in perovskite solar cells(PSCs), achieving high power conversion efficiencies(PCE) over 26%^([1, 2]).展开更多
Lime is widely used to modify clayey soils to enhance their physical and chemical properties,and lime-treated soil has become a key material in transportation infrastructure.Chemical reactions were identified through ...Lime is widely used to modify clayey soils to enhance their physical and chemical properties,and lime-treated soil has become a key material in transportation infrastructure.Chemical reactions were identified through laboratory tests from field samples collected from the subgrade after 30 years of operation to understand its long-term performance evolution.Exchangeable calcium,carbonated calcium,and total calcium were quantified using ethylenediaminetetraacetic acid(EDTA)titration,gasometric analysis,and the strong acid extraction method,respectively.These measurements enabled the evaluation of calcium transformation during the pozzolanic reaction,providing a quantitative characterization of pozzolanic progression in the lime-treated clay matrix.Evolutions in pH,electrical conductivity,and salinity were also tracked.Mechanical performance was assessed through maximal shear modulus(Gmax)and unconfined compressive strength(UCS)tests.Then,the microstructure and mineral composition were analyzed via scanning electron microscopy(SEM)and X-ray diffraction(XRD).Furthermore,with an extended curing period,the pH,electrical conductivity,salinity,and exchangeable calcium content were found to decrease gradually.In contrast,the carbonation-related calcium content increased,and the clay mineral structures were significantly altered.The significant increase in Gmax and UCS is attributed to the formation of calcium-aluminate-silicate-hydrate(C-(A)-S-H)for pozzolanic and carbonation reactions where the clay mineral is involved.SEM reveals the curled edges of clay minerals and the formation of a 3D network.Additionally,XRD patterns further confirm the presence of increasing amounts of amorphous phases within the 2θrange of 15°–32°,indicating the progression of the pozzolanic reaction.展开更多
Aqueous zincion batteries are highly favored for grid-level energy storage owing to their low cost and high safety,but their practical application is limited by slow ion migration.To address this,a strategy has been d...Aqueous zincion batteries are highly favored for grid-level energy storage owing to their low cost and high safety,but their practical application is limited by slow ion migration.To address this,a strategy has been developed to create a cation-accelerating electric field on the surface of the cathode to achieve ultrafast Zn^(2+)diffusion kinetics.By employing electrodeposition to coat MoS_(2)on the surface of BaV_(6)O_(16)·3H_(2)O nanowires,the directional builtin electric field generated at the heterointerface acts as a cation accelerator,continuously accelerating Zn^(2+)diffusion into the active material.The optimized Zn^(2+)diffusion coefficient in CC@BaV-V_(6)O_(16)·3H_(2)@MoS_(2)(7.5×10^(8)cm^(2)s^(-1)) surpasses that of most reported V-based cathodes.Simultaneously,MoS_(2)serving as a cathodic armor extends the cycling life of the Zn-CC@BaV_(6)O_(16)·3H_(2)@MoS_(2)full batteries to over 10000 cycles.This work provides valuable insights into optimizing ion diffusion kinetics for high-performance energy storage devices.展开更多
Symmetric secondary batteries are expected to become promising storage devices on account of their low cost,environmentally friendly and high safety.Nevertheless,the further development of symmetric batteries needs to...Symmetric secondary batteries are expected to become promising storage devices on account of their low cost,environmentally friendly and high safety.Nevertheless,the further development of symmetric batteries needs to rely on bipolar electrodes with superior performance.Cation-disordered rocksalt(DRX)Li_(2)FeTiO_(4)shows promising properties as symmetric electrodes,based on the ability of iron to undergo multiple electrochemical reactions over a wide voltage window.Unfortunately,this cation-disordered structure would not provide a cross-path for the rapid migration of Li^(+),ultimately resulting in inferior electrochemical dynamics and cycle stability.Herein,Li_(2)FeTiO_(4)nanoparticles assembled by ultrafine nanocrystals are synthesized via a sol-gel method through an orderly reaction regulation strategy of precursor reactants.Such ultrafine nanocrystals increase the active sites to promote the reversibility of multi-cationic(e.g.,stable Fe^(2+)/Fe^(3+),Ti^(3+)/Ti^(4+)and moderated Fe^(3+)/Fe^(4+))and anionic redox,and maintain the DRX structure well during the cycling process.The half cells with nano-sized Li_(2)FeTiO_(4)as the cathode/anode exhibit a high reversible capacity of 127.8/500.8 mAh/g,respectively.Besides,the Li_(2)FeTiO_(4)//Li_(2)FeTiO_(4)symmetric full cell could provide a reversible capacity of 95.4 mAh/g at 0.1 A/g after 200 cycles.This hierarchical self-assembly by nanocrystal strategy could offer effective guidance for high-performance electrode design for rechargeable secondary batteries.展开更多
Modal parameters can accurately characterize the structural dynamic properties and assess the physical state of the structure.Therefore,it is particularly significant to identify the structural modal parameters accordi...Modal parameters can accurately characterize the structural dynamic properties and assess the physical state of the structure.Therefore,it is particularly significant to identify the structural modal parameters according to the monitoring data information in the structural health monitoring(SHM)system,so as to provide a scientific basis for structural damage identification and dynamic model modification.In view of this,this paper reviews methods for identifying structural modal parameters under environmental excitation and briefly describes how to identify structural damages based on the derived modal parameters.The paper primarily introduces data-driven modal parameter recognition methods(e.g.,time-domain,frequency-domain,and time-frequency-domain methods,etc.),briefly describes damage identification methods based on the variations of modal parameters(e.g.,natural frequency,modal shapes,and curvature modal shapes,etc.)and modal validation methods(e.g.,Stability Diagram and Modal Assurance Criterion,etc.).The current status of the application of artificial intelligence(AI)methods in the direction of modal parameter recognition and damage identification is further discussed.Based on the pre-vious analysis,the main development trends of structural modal parameter recognition and damage identification methods are given to provide scientific references for the optimized design and functional upgrading of SHM systems.展开更多
Although the Mg-air battery with high theoretical energy density is desirable for the energy supply of marine engineering equipment,its applications remain limited due to the low actual discharge voltage and inferior ...Although the Mg-air battery with high theoretical energy density is desirable for the energy supply of marine engineering equipment,its applications remain limited due to the low actual discharge voltage and inferior Mg anode utilization rate.In addition to the microstructure of Mg alloy anodes,the properties of discharge product films are of great importance to the discharge performance.Herein,the discharge behaviors of Mg-Y-Zn alloys are first studied mainly from the perspective of film properties.Through contrastive analysis,it is found that the sufficient Y^(3+) produced during the discharge process can substitute Mg^(2+) in Mg(OH)_(2) to introduce effective cation vacancies.The Mg-Y-Zn anode with profuse cation vacancies in the product film shows a synergy of potential and efficiency,and this can be attributed to an increase in the migration pathway for Mg^(2+),reducing the diffusion over-potential caused by the protective product film.This study is expected to provide a new strategy from the perspective of cation vacancy design of discharge film for developing high-performance Mg-air batteries.展开更多
The development of flexible zinc-ion batteries(ZIBs)faces a threeway trade-off among the ionic conductivity,Zn^(2+)mobility,and the electrochemical stability of hydrogel electrolytes.To address this challenge,we desig...The development of flexible zinc-ion batteries(ZIBs)faces a threeway trade-off among the ionic conductivity,Zn^(2+)mobility,and the electrochemical stability of hydrogel electrolytes.To address this challenge,we designed a cationic hydrogel named PAPTMA to holistically improve the reversibility of ZIBs.The long cationic branch chains in the polymeric matrix construct express pathways for rapid Zn^(2+)transport through an ionic repulsion mechanism,achieving simultaneously high Zn^(2+)transference number(0.79)and high ionic conductivity(28.7 mS cm−1).Additionally,the reactivity of water in the PAPTMA hydrogels is significantly inhibited,thus possessing a strong resistance to parasitic reactions.Mechanical characterization further reveals the superior tensile and adhesion strength of PAPTMA.Leveraging these properties,symmetric batteries employing PAPTMA hydrogel deliver exceeding 6000 h of reversible cycling at 1 mA cm^(−2) and maintain stable operation for 1000 h with a discharge of depth of 71%.When applied in 4×4 cm2 pouch cells with MnO_(2) as the cathode material,the device demonstrates remarkable operational stability and mechanical robustness through 150 cycles.This work presents an eclectic strategy for designing advanced hydrogels that combine high ionic conductivity,enhanced Zn^(2+)mobility,and strong resistance to parasitic reactions,paving the way for long-lasting flexible ZIBs.展开更多
Oxygen evolution reaction(OER)is often regarded as a crucial bottleneck in the field of renewable energy storage and conversion.To further accelerate the sluggish kinetics of OER,a cation and anion modulation strategy...Oxygen evolution reaction(OER)is often regarded as a crucial bottleneck in the field of renewable energy storage and conversion.To further accelerate the sluggish kinetics of OER,a cation and anion modulation strategy is reported here,which has been proven to be effective in preparing highly active electrocatalyst.For example,the cobalt,sulfur,and phosphorus modulated nickel hydroxide(denoted as NiCoPSOH)only needs an overpotential of 232 mV to reach a current density of 20 mA cm^(–2),demonstrating excellent OER performances.The cation and anion modulation facilitates the generation of high-valent Ni species,which would activate the lattice oxygen and switch the OER reaction pathway from conventional adsorbate evolution mechanism to lattice oxygen mechanism(LOM),as evidenced by the results of electrochemical measurements,Raman spectroscopy and differential electrochemical mass spectrometry.The LOM pathway of NiCoPSOH is further verified by the theoretical calculations,including the upshift of O 2p band center,the weakened Ni–O bond and the lowest energy barrier of rate-limiting step.Thus,the anion and cation modulated catalyst NiCoPSOH could effectively accelerate the sluggish OER kinetics.Our work provides a new insight into the cation and anion modulation,and broadens the possibility for the rational design of highly active electrocatalysts.展开更多
The implementation of ultrahigh-Ni cathodes in high-energy lithium-ion batteries(LIBs)is constrained by significant structural and interfacial degradation during cycling.In this study,doping-induced surface restructur...The implementation of ultrahigh-Ni cathodes in high-energy lithium-ion batteries(LIBs)is constrained by significant structural and interfacial degradation during cycling.In this study,doping-induced surface restructuring in ultrahigh-nickel cathode materials is rapidly facilitated through an ultrafast Joule heating method.Density functional theory(DFT)calculations,synchrotron X-ray absorption spectroscopy(XAS),and single-particle force test confirmed the establishment of a stable crystal framework and lattice oxygen,which mitigated H2-H3 phase transitions and improved structural reversibility.Additionally,the Sc doping process exhibits a pinning effect on the grain boundaries,as shown by scanning transmission electron microscopy(STEM),enhancing Li~+diffusion kinetics and decreasing mechanical strain during cycling.The in situ development of a cation-mixing layer at grain boundaries also creates a robust cathode/electrolyte interphase,effectively reducing interfacial parasitic reactions and transition metal dissolution,as validated by STEM and time-of-flight secondary ion mass spectrometry(TOF-SIMS).These synergistic modifications reduce particle cracking and surface/interface degradation,leading to enhanced rate capability,structural integrity,and thermal stability.Consequently,the optimized Sc-modified ultrahigh-Ni cathode(Sc-1)exhibits 93.99%capacity retention after 100 cycles at 1 C(25℃)and87.06%capacity retention after 100 cycles at 1 C(50℃),indicating excellent cycling and thermal stability.By presenting a one-step multifunctional modification approach,this research delivers an extensive analysis of the mechanisms governing the structure,microstructure,and interface properties of nickel-rich layered cathode materials(NCMs).These results underscore the potential of ultrahigh-Ni cathodes as viable candidates for advanced lithium-ion batteries(LIBs)in next-generation electric vehicles(EVs).展开更多
Posaconazole(PCZ)is a broad-spectrum anti-fungal drug approved by FDA and currently used off-label for the treatment of fungal keratitis(FK).Although ocular route serves as the most bioavailable route for treating FK,...Posaconazole(PCZ)is a broad-spectrum anti-fungal drug approved by FDA and currently used off-label for the treatment of fungal keratitis(FK).Although ocular route serves as the most bioavailable route for treating FK,delivery of PCZ to the eye remains a challenge due to poor permeation though the cornea and rapid elimination from the eye.Here we outline a comprehensive formulation development process,beginning with in silico studies,progressing through in vitro evaluations,and ultimately achieving therapeutic benefits in vivo.We report modified niosome-like surfactant vesicles,hereafter termed as NioTherms,formulated using a novel and simple heat-mix method,encapsulating PCZ for ocular administration in the form of an in situ gel.Excipient screening performed using in silico simulations highly correlate with in vitro studies(R^(2)=0.77),guiding optimization by Quality by Design(QbD)approach for encapsulating PCZ in NioTherms resulting in particles with an average size of 180.7±2.3 nm,zeta potential of +27.5±2.2 mV and entrapment efficiency of 87.6%±1.7%.A 2-fold increase in both mucin binding and cellular uptake indicates a functional role of positive surface charge in enhancingmucoadhesive properties of PCZ-NioTherms.In an in vivo murine ocular keratitis model,we demonstrate a 2-fold enhancement in trans-corneal permeability of PCZ-NioTherms and a 3-fold reduction in fungal burden compared to the control standard of care,the PCZ solution.Owing to a facile formulation process,we anticipate that PCZ-NioTherms would serve as a clinically translatable and patient compliant therapeutic intervention for treating FK.展开更多
Transition metal carbonates(TMCs)hold great potential as high-performance electrodes for alkali metal-ion batteries,owing to multiple-ion storage mechanisms involving conversion process and electrocatalytic reaction.H...Transition metal carbonates(TMCs)hold great potential as high-performance electrodes for alkali metal-ion batteries,owing to multiple-ion storage mechanisms involving conversion process and electrocatalytic reaction.However,they still suffer from inferior electronic conductivity and volume variation during delithiation/lithiation.Heterostructure and heteroatoms doping offer immense promise in enhancing reaction kinetics and structural integrity,which unfortunately have not been achieved in TMCs.Herein,a unique TMCs heterostructure with Ni-doped MnCO_(3)as“core”and Mn-doped NiCO_(3)as“shell”,which is wrapped by graphene(NM@MN/RGO),is achieved by cations differentiation strategy.The formation process for core-shell NM@MN consists of epitaxial growth of NiCO_(3)from MnCO_(3)and synchronously mutual doping,owing to the similar crystal structures but different solubility product constant/formation energy of MnCO_(3)and NiCO_(3).In-situ electrochemical impedance spectroscopy,galvanostatic intermittent titration technique,differential capacity versus voltage plots,theoretical calculation and kinetic analysis reveal the superior electrochemical activity of the NM@MN/RGO to MnCO_(3)/RGO.The NM@MN/RGO shows excellent lithium storage properties(1013.4 mAh·g^(-1)at 0.1 A·g^(-1)and 760 mAh·g^(-1)after 1000 cycles at 2 A·g^(-1))and potassium storage properties(capacity decay rate of 0.114 mAh·g^(-1)per cycle).This work proposes an efficient cation differentiation strategy for constructing advanced TMC electrodes.展开更多
Developing cost-effective single-crystalline Ni-rich Co-poor cathodes operating at high-voltage is one of the most important ways to achieve higher energy Li-ion batteries. However, the Li/O loss and Li/Ni mixing unde...Developing cost-effective single-crystalline Ni-rich Co-poor cathodes operating at high-voltage is one of the most important ways to achieve higher energy Li-ion batteries. However, the Li/O loss and Li/Ni mixing under high-temperature lithiation result in electrochemical kinetic hysteresis and structural instability. Herein, we report a highly-ordered single-crystalline LiNi0.85Co0.05Mn0.10O2(NCM85) cathode by doping K+and F-ions. To be specific, the K-ion as a fluxing agent can remarkably decrease the solid-state lithiation temperature by ~30°C, leading to less Li/Ni mixing and oxygen vacancy. Meanwhile, the strong transitional metal(TM)-F bonds are helpful for enhancing de-/lithiation kinetics and limiting the lattice oxygen escape even at 4.5 V high-voltage. Their advantages synergistically endow the single-crystalline NCM85 cathode with a very high reversible capacity of 222.3 mAh g-1. A superior capacity retention of 91.3% is obtained after 500 times at 1 C in pouch-type full cells, and a prediction value of 75.3% is given after cycling for 5000 h. These findings are reckoned to expedite the exploitation and application of high-voltage single-crystalline Ni-rich cathodes for next-generation Li-ion batteries.展开更多
Incorporating organic bulky cations in the precursor or post-treatment to achieve two-dimensional/thr ee-dimensional(2D/3D)heterojunction is an effective strategy for enhancing the stability of perovskite materials.Ho...Incorporating organic bulky cations in the precursor or post-treatment to achieve two-dimensional/thr ee-dimensional(2D/3D)heterojunction is an effective strategy for enhancing the stability of perovskite materials.However,the issue of insufficient charge transport in 2D perovskites limits their development,and the fundamental mechanism of out-of-plane carrier transport remains unclear.This study designed and synthesized seven organic phenyl-core cations,differentiated at the 1-and 1,4-positions,and identified the impacts on the corresponding properties of the 2D crystalline perovskite.Shorter cations facilitated a more compact arrangement of adjacent inorganic layers,aligning to favor charge transport along the vertical direction.In addition,introducing high electronegativity led to increased intermolecular interactions,resulting in enhanced structural stability and improved phenyl ring π-orbital overlap and interlayer electron coupling,yielding efficient charge transport.Resilience to thermal stressing of the perovskite was strongly correlated with the carbon chain length of the spacer cations.The increase in cation length and the reduction in the rigidity of the amino-terminal both aided in the dispersion of thermal stress in the inorganic framework.Additional hydrogen bonding also contributed to mitigating structural disorder.展开更多
The first-ever synthesis of the unknown furo[2,3:4,5]pyrimido[1,2-b]indazole skeleton was demonstrated based on the undiscovered tetra-functionalization of enaminones,with simple substrates and reaction conditions.The...The first-ever synthesis of the unknown furo[2,3:4,5]pyrimido[1,2-b]indazole skeleton was demonstrated based on the undiscovered tetra-functionalization of enaminones,with simple substrates and reaction conditions.The key to realizing this process lies in the multiple trapping of the in situ generated ketenimine cation by the 3-aminoindazole,which results in the formation of four new chemical bonds and two new rings in one pot.Moreover,the products of this new reaction were found to exhibit aggregationinduced emission(AIE)without modification.展开更多
Dendrite growth represents one of the most significant challenges that impede the development of aqueous zinc-ion batteries.Herein,Gd^(3+)ions are introduced into conventional electrolytes as a microlevelling agent to...Dendrite growth represents one of the most significant challenges that impede the development of aqueous zinc-ion batteries.Herein,Gd^(3+)ions are introduced into conventional electrolytes as a microlevelling agent to achieve dendrite-free zinc electrodeposition.Simulation and experimental results demonstrate that these Gd^(3+)ions are preferentially adsorbed onto the zinc surface,which enables dendritefree zinc anodes by activating the microlevelling effect during electrodeposition.In addition,the Gd^(3+)additives effectively inhibit side reactions and facilitate the desolvation of[Zn(H_(2)O)_(6)]^(2+),leading to highly reversible zinc plating/stripping.Due to these improvements,the zinc anode demonstrates a significantly prolonged cycle life of 2100 h and achieves an exceptional average Coulombic efficiency of 99.72%over 1400 cycles.More importantly,the Zn//NH_(4)V_(4)O_(10)full cell shows a high capacity retention rate of 85.6%after 1000 cycles.This work not only broadens the application of metallic cations in battery electrolytes but also provides fundamental insights into their working mechanisms.展开更多
Despite the growing interest in fast-cha rging solid-state lithium(Li)-metal batteries(SSLMBs),their practical implementation has yet to be achieved,primarily due to an incomplete understanding of the disparate and of...Despite the growing interest in fast-cha rging solid-state lithium(Li)-metal batteries(SSLMBs),their practical implementation has yet to be achieved,primarily due to an incomplete understanding of the disparate and often conflicting requirements of the bulk electrolyte and the electrode-electrolyte interphase.Here,we present a weakly coordinating cationic polymer electrolyte(WCPE)specifically designed to regulate the Li^(+)coordination structure,thereby enabling fast-charging SSLMBs.The WCPE comprises an imidazolium-based polycationic matrix combined with a succinonitrile(SN)-based highconcentration electrolyte.Unlike conventional neutral polymer matrices,the polycationic matrix in the WCPE competes with Li^(+)for interactions with SN,weakening the original coordination between SN and Li^(+).This modulation of SN-Li^(+)interaction improves both Li^(+)conductivity of the WCPE(σ_(Li^(+))=1.29mS cm^(-1))and redox kinetics at the electrode-electrolyte interphase.Consequently,SSLMB cells(comprising LiFePO_(4)cathodes and Li-metal anodes)with the WCPE achieve fast-charging capability(reaching over 80%state of charge within 10 min),outperforming those of previously reported polymer electrolytebased SSLMBs.展开更多
Most of the international accreditation bodies in engineering education(e.g.,ABET)and outcome-based educational systems have based their assess-ments on learning outcomes and program educational objectives.However,map...Most of the international accreditation bodies in engineering education(e.g.,ABET)and outcome-based educational systems have based their assess-ments on learning outcomes and program educational objectives.However,map-ping program educational objectives(PEOs)to student outcomes(SOs)is a challenging and time-consuming task,especially for a new program which is applying for ABET-EAC(American Board for Engineering and Technology the American Board for Engineering and Technology—Engineering Accreditation Commission)accreditation.In addition,ABET needs to automatically ensure that the mapping(classification)is reasonable and correct.The classification also plays a vital role in the assessment of students’learning.Since the PEOs are expressed as short text,they do not contain enough semantic meaning and information,and consequently they suffer from high sparseness,multidimensionality and the curse of dimensionality.In this work,a novel associative short text classification tech-nique is proposed to map PEOs to SOs.The datasets are extracted from 152 self-study reports(SSRs)that were produced in operational settings in an engineering program accredited by ABET-EAC.The datasets are processed and transformed into a representational form appropriate for association rule mining.The extracted rules are utilized as delegate classifiers to map PEOs to SOs.The proposed asso-ciative classification of the mapping of PEOs to SOs has shown promising results,which can simplify the classification of short text and avoid many problems caused by enriching short text based on external resources that are not related or relevant to the dataset.展开更多
Living cationic polymerization of 4-acetoxystyrene(STO)was conducted in CH_(2)Cl_(2) at-15℃ using a dicumyl chloride(DCC)/SnCl_(4)/nBu_(4)NBr initiating system.Impurity moisture initiation was inhibited by adding pro...Living cationic polymerization of 4-acetoxystyrene(STO)was conducted in CH_(2)Cl_(2) at-15℃ using a dicumyl chloride(DCC)/SnCl_(4)/nBu_(4)NBr initiating system.Impurity moisture initiation was inhibited by adding proton trap 2,6-di-tert-butylpyridine(DTBP),and the controlled initiation of DCC was confirmed by ^(1)H nuclear magnetic resonance(^(1)H-NMR)spectroscopy and matrix-assisted laser desorption ionization time-offlight mass(MALDI-TOF-MS)spectrometry.The polymerization kinetics were analyzed to for optimizing the polymerization rate.Allyl-telechelic PSTOs(allyl-PSTO-allyl)with molecular weight(Mn)range of 3540–7800 g/mol and narrow molecular weight dispersity(Mw/Mn)about 1.25 were prepared through nucleophilic substitution with allyltrimethylsilane(ATMS)at approximately 40%monomer conversion.The experimental results indicate that the substitution efficiency of ATMS increased with higher ATMS concentration,temperature,and extended reaction time.Nearly unity ally-functionality for allyl-PSTO-allyl was achieved by adding sufficient SnCl_(4) prior to the substitution.展开更多
Cation segregation on cathode surfaces plays a key role in determining the activity and operational stability of solid oxide fuel cells(SOFCs).The double perovskite oxide PrBa_(0.8)Ca_(0.2)Co_(2)O_(5+δ)(PBCC)has been...Cation segregation on cathode surfaces plays a key role in determining the activity and operational stability of solid oxide fuel cells(SOFCs).The double perovskite oxide PrBa_(0.8)Ca_(0.2)Co_(2)O_(5+δ)(PBCC)has been widely studied as an active cathode but still suffer from serious detrimental segregations.To enhance the cathode stability,a PBCC derived A-site medium-entropy Pr_(0.6)La_(0.1)Nd_(0.1)Sm_(0.1)Gd_(0.1)Ba_(0.8)Ca_(0.2)Co_(2)O_(5+δ)(ME-PBCC)oxide was prepared and its segregation behaviors were investigated under different conditions.Compared with initial PBCC oxide,the segregations of BaO and Co_(3)O_(4)on the surface of ME-PBCC material are significantly suppressed,especially for Co_(3)O_(4),which is attributed to its higher configuration entropy.Our results also confirm the improved electrochemical performance and structural stability of ME-PBCC material,enabling it as a promising cathode for SOFCs.展开更多
基金financially supported by the Excellent Youth Scholars Program of State Key Laboratory of Complex Nonferrous Metal Resource Clean Utilization,Kunming University of Science and Technology,China(No.YXQN-2024003)the Central Government-Guided Local Science and Technology Development Fund Project,China(No.202407AB110022)。
文摘The rapid advancement of modern science and technology,coupled with the recent surge in new-energy electric vehicles,has significantly boosted the demand for lithium.This has promoted the development and efficient utilization of lepidolite as a lithium source.Therefore,the processes for the flotation of lepidolite have been studied in depth,particularly the development and use of lepidolite flotation collectors and the action mechanism of the collectors on the lepidolite surface.Based on the crystal-structure characteristics of lepidolite minerals,this review focuses on the application of anionic collectors,amine cationic collectors(primary amines,quaternary ammonium salts,ether amines,and Gemini amines),and combined collectors to the flotation behavior of lepidolite as well as the adsorption mechanisms.New directions and technologies for the controllable flotation of lepidolite are proposed,including process improvement,reagent synthesis,and mechanistic research.This analysis demonstrates the need for the further study of the complex environment inside lepidolite and pulp.By using modern analytical detection methods and quantum chemical calculations,research on reagents for the flotation of lepidolite has expanded,providing new concepts and references for the efficient flotation recovery and utilization of lepidolite.
基金financially supported by the National Natural Science Foundation of China (52462032, 62274018, 52462031)Natural Science Foundation of Yunnan Province (202501AT070353, 202101BE070001-049)+2 种基金the Xinjiang Construction Corps Key Areas of Science and Technology Research Project (2023AB029)the Tianchi Talent Program of Xinjiang Uygur Autonomous Region (2024, Jiangzhao Chen)the Key Project of Chongqing Overseas Students Returning to China Entrepreneurship and Innovation Support Plan (cx2023006)。
文摘In recent years, the research advancements have high-lighted the critical role of the A-site cation in determining the optoelectronic and physicochemical properties of organicinorganic lead halide perovskites. Mixed-cation perovskites(MCPs) have been extensively used as absorber thin films in perovskite solar cells(PSCs), achieving high power conversion efficiencies(PCE) over 26%^([1, 2]).
基金supported by the National Natural Science Foundation of China(Grant No.42302311)the ARC Discovery Project Program(Grant Nos.DP210100437 and DP230100126).
文摘Lime is widely used to modify clayey soils to enhance their physical and chemical properties,and lime-treated soil has become a key material in transportation infrastructure.Chemical reactions were identified through laboratory tests from field samples collected from the subgrade after 30 years of operation to understand its long-term performance evolution.Exchangeable calcium,carbonated calcium,and total calcium were quantified using ethylenediaminetetraacetic acid(EDTA)titration,gasometric analysis,and the strong acid extraction method,respectively.These measurements enabled the evaluation of calcium transformation during the pozzolanic reaction,providing a quantitative characterization of pozzolanic progression in the lime-treated clay matrix.Evolutions in pH,electrical conductivity,and salinity were also tracked.Mechanical performance was assessed through maximal shear modulus(Gmax)and unconfined compressive strength(UCS)tests.Then,the microstructure and mineral composition were analyzed via scanning electron microscopy(SEM)and X-ray diffraction(XRD).Furthermore,with an extended curing period,the pH,electrical conductivity,salinity,and exchangeable calcium content were found to decrease gradually.In contrast,the carbonation-related calcium content increased,and the clay mineral structures were significantly altered.The significant increase in Gmax and UCS is attributed to the formation of calcium-aluminate-silicate-hydrate(C-(A)-S-H)for pozzolanic and carbonation reactions where the clay mineral is involved.SEM reveals the curled edges of clay minerals and the formation of a 3D network.Additionally,XRD patterns further confirm the presence of increasing amounts of amorphous phases within the 2θrange of 15°–32°,indicating the progression of the pozzolanic reaction.
基金National Natural Science Foundation of China (61761047 and 41876055)Program for Innovative Research Team (in Science and Technology) in University of Yunnan Province。
文摘Aqueous zincion batteries are highly favored for grid-level energy storage owing to their low cost and high safety,but their practical application is limited by slow ion migration.To address this,a strategy has been developed to create a cation-accelerating electric field on the surface of the cathode to achieve ultrafast Zn^(2+)diffusion kinetics.By employing electrodeposition to coat MoS_(2)on the surface of BaV_(6)O_(16)·3H_(2)O nanowires,the directional builtin electric field generated at the heterointerface acts as a cation accelerator,continuously accelerating Zn^(2+)diffusion into the active material.The optimized Zn^(2+)diffusion coefficient in CC@BaV-V_(6)O_(16)·3H_(2)@MoS_(2)(7.5×10^(8)cm^(2)s^(-1)) surpasses that of most reported V-based cathodes.Simultaneously,MoS_(2)serving as a cathodic armor extends the cycling life of the Zn-CC@BaV_(6)O_(16)·3H_(2)@MoS_(2)full batteries to over 10000 cycles.This work provides valuable insights into optimizing ion diffusion kinetics for high-performance energy storage devices.
基金supported by the National Natural Science Foundation of China(No.22278347)the Excellent Doctoral Student Research Innovation Project of Xinjiang University of China(No.XJU2022BS048)the Postgraduate Innovation Project of Xinjiang Uygur Autonomous Region of China(No.XJ2023G027)。
文摘Symmetric secondary batteries are expected to become promising storage devices on account of their low cost,environmentally friendly and high safety.Nevertheless,the further development of symmetric batteries needs to rely on bipolar electrodes with superior performance.Cation-disordered rocksalt(DRX)Li_(2)FeTiO_(4)shows promising properties as symmetric electrodes,based on the ability of iron to undergo multiple electrochemical reactions over a wide voltage window.Unfortunately,this cation-disordered structure would not provide a cross-path for the rapid migration of Li^(+),ultimately resulting in inferior electrochemical dynamics and cycle stability.Herein,Li_(2)FeTiO_(4)nanoparticles assembled by ultrafine nanocrystals are synthesized via a sol-gel method through an orderly reaction regulation strategy of precursor reactants.Such ultrafine nanocrystals increase the active sites to promote the reversibility of multi-cationic(e.g.,stable Fe^(2+)/Fe^(3+),Ti^(3+)/Ti^(4+)and moderated Fe^(3+)/Fe^(4+))and anionic redox,and maintain the DRX structure well during the cycling process.The half cells with nano-sized Li_(2)FeTiO_(4)as the cathode/anode exhibit a high reversible capacity of 127.8/500.8 mAh/g,respectively.Besides,the Li_(2)FeTiO_(4)//Li_(2)FeTiO_(4)symmetric full cell could provide a reversible capacity of 95.4 mAh/g at 0.1 A/g after 200 cycles.This hierarchical self-assembly by nanocrystal strategy could offer effective guidance for high-performance electrode design for rechargeable secondary batteries.
基金supported by the Innovation Foundation of Provincial Education Department of Gansu(2024B-005)the Gansu Province National Science Foundation(22YF7GA182)the Fundamental Research Funds for the Central Universities(No.lzujbky2022-kb01)。
文摘Modal parameters can accurately characterize the structural dynamic properties and assess the physical state of the structure.Therefore,it is particularly significant to identify the structural modal parameters according to the monitoring data information in the structural health monitoring(SHM)system,so as to provide a scientific basis for structural damage identification and dynamic model modification.In view of this,this paper reviews methods for identifying structural modal parameters under environmental excitation and briefly describes how to identify structural damages based on the derived modal parameters.The paper primarily introduces data-driven modal parameter recognition methods(e.g.,time-domain,frequency-domain,and time-frequency-domain methods,etc.),briefly describes damage identification methods based on the variations of modal parameters(e.g.,natural frequency,modal shapes,and curvature modal shapes,etc.)and modal validation methods(e.g.,Stability Diagram and Modal Assurance Criterion,etc.).The current status of the application of artificial intelligence(AI)methods in the direction of modal parameter recognition and damage identification is further discussed.Based on the pre-vious analysis,the main development trends of structural modal parameter recognition and damage identification methods are given to provide scientific references for the optimized design and functional upgrading of SHM systems.
基金support of the Natural Science Foundation of Heilongjiang Province of China(No.LH2023E059)the National Natural Science Foundation of China(No.52071093)the Opening Project of Jiangsu Key Laboratory of Advanced Structural Materials and Application Technology(No.ASMA202205).
文摘Although the Mg-air battery with high theoretical energy density is desirable for the energy supply of marine engineering equipment,its applications remain limited due to the low actual discharge voltage and inferior Mg anode utilization rate.In addition to the microstructure of Mg alloy anodes,the properties of discharge product films are of great importance to the discharge performance.Herein,the discharge behaviors of Mg-Y-Zn alloys are first studied mainly from the perspective of film properties.Through contrastive analysis,it is found that the sufficient Y^(3+) produced during the discharge process can substitute Mg^(2+) in Mg(OH)_(2) to introduce effective cation vacancies.The Mg-Y-Zn anode with profuse cation vacancies in the product film shows a synergy of potential and efficiency,and this can be attributed to an increase in the migration pathway for Mg^(2+),reducing the diffusion over-potential caused by the protective product film.This study is expected to provide a new strategy from the perspective of cation vacancy design of discharge film for developing high-performance Mg-air batteries.
基金financially supported by the General Research Fund(CityU 11315622 and CityU 11310123)National Natural Science Foundation(NSFC 52372229 and NSFC 52172241)+3 种基金Green Tech Fund(GTF202220105)Guangdong Basic and Applied Basic Research Foundation(2024A1515011008)City University of Hong Kong(No.9020002)the Shenzhen Research Institute of City University of Hong Kong.
文摘The development of flexible zinc-ion batteries(ZIBs)faces a threeway trade-off among the ionic conductivity,Zn^(2+)mobility,and the electrochemical stability of hydrogel electrolytes.To address this challenge,we designed a cationic hydrogel named PAPTMA to holistically improve the reversibility of ZIBs.The long cationic branch chains in the polymeric matrix construct express pathways for rapid Zn^(2+)transport through an ionic repulsion mechanism,achieving simultaneously high Zn^(2+)transference number(0.79)and high ionic conductivity(28.7 mS cm−1).Additionally,the reactivity of water in the PAPTMA hydrogels is significantly inhibited,thus possessing a strong resistance to parasitic reactions.Mechanical characterization further reveals the superior tensile and adhesion strength of PAPTMA.Leveraging these properties,symmetric batteries employing PAPTMA hydrogel deliver exceeding 6000 h of reversible cycling at 1 mA cm^(−2) and maintain stable operation for 1000 h with a discharge of depth of 71%.When applied in 4×4 cm2 pouch cells with MnO_(2) as the cathode material,the device demonstrates remarkable operational stability and mechanical robustness through 150 cycles.This work presents an eclectic strategy for designing advanced hydrogels that combine high ionic conductivity,enhanced Zn^(2+)mobility,and strong resistance to parasitic reactions,paving the way for long-lasting flexible ZIBs.
文摘Oxygen evolution reaction(OER)is often regarded as a crucial bottleneck in the field of renewable energy storage and conversion.To further accelerate the sluggish kinetics of OER,a cation and anion modulation strategy is reported here,which has been proven to be effective in preparing highly active electrocatalyst.For example,the cobalt,sulfur,and phosphorus modulated nickel hydroxide(denoted as NiCoPSOH)only needs an overpotential of 232 mV to reach a current density of 20 mA cm^(–2),demonstrating excellent OER performances.The cation and anion modulation facilitates the generation of high-valent Ni species,which would activate the lattice oxygen and switch the OER reaction pathway from conventional adsorbate evolution mechanism to lattice oxygen mechanism(LOM),as evidenced by the results of electrochemical measurements,Raman spectroscopy and differential electrochemical mass spectrometry.The LOM pathway of NiCoPSOH is further verified by the theoretical calculations,including the upshift of O 2p band center,the weakened Ni–O bond and the lowest energy barrier of rate-limiting step.Thus,the anion and cation modulated catalyst NiCoPSOH could effectively accelerate the sluggish OER kinetics.Our work provides a new insight into the cation and anion modulation,and broadens the possibility for the rational design of highly active electrocatalysts.
基金supported by the National Key R&D Program of China(2022YFB3803501)the National Natural Science Foundation of China(22179008,22209156)+5 种基金support from the Beijing Nova Program(20230484241)support from the China Postdoctoral Science Foundation(2024M754084)the Postdoctoral Fellowship Program of CPSF(GZB20230931)support from beamline BL08U1A of Shanghai Synchrotron Radiation Facility(2024-SSRF-PT-506950)beamline 1W1B of the Beijing Synchrotron Radiation Facility(2021-BEPC-PT-006276)support from Initial Energy Science&Technology Co.,Ltd(IEST)。
文摘The implementation of ultrahigh-Ni cathodes in high-energy lithium-ion batteries(LIBs)is constrained by significant structural and interfacial degradation during cycling.In this study,doping-induced surface restructuring in ultrahigh-nickel cathode materials is rapidly facilitated through an ultrafast Joule heating method.Density functional theory(DFT)calculations,synchrotron X-ray absorption spectroscopy(XAS),and single-particle force test confirmed the establishment of a stable crystal framework and lattice oxygen,which mitigated H2-H3 phase transitions and improved structural reversibility.Additionally,the Sc doping process exhibits a pinning effect on the grain boundaries,as shown by scanning transmission electron microscopy(STEM),enhancing Li~+diffusion kinetics and decreasing mechanical strain during cycling.The in situ development of a cation-mixing layer at grain boundaries also creates a robust cathode/electrolyte interphase,effectively reducing interfacial parasitic reactions and transition metal dissolution,as validated by STEM and time-of-flight secondary ion mass spectrometry(TOF-SIMS).These synergistic modifications reduce particle cracking and surface/interface degradation,leading to enhanced rate capability,structural integrity,and thermal stability.Consequently,the optimized Sc-modified ultrahigh-Ni cathode(Sc-1)exhibits 93.99%capacity retention after 100 cycles at 1 C(25℃)and87.06%capacity retention after 100 cycles at 1 C(50℃),indicating excellent cycling and thermal stability.By presenting a one-step multifunctional modification approach,this research delivers an extensive analysis of the mechanisms governing the structure,microstructure,and interface properties of nickel-rich layered cathode materials(NCMs).These results underscore the potential of ultrahigh-Ni cathodes as viable candidates for advanced lithium-ion batteries(LIBs)in next-generation electric vehicles(EVs).
文摘Posaconazole(PCZ)is a broad-spectrum anti-fungal drug approved by FDA and currently used off-label for the treatment of fungal keratitis(FK).Although ocular route serves as the most bioavailable route for treating FK,delivery of PCZ to the eye remains a challenge due to poor permeation though the cornea and rapid elimination from the eye.Here we outline a comprehensive formulation development process,beginning with in silico studies,progressing through in vitro evaluations,and ultimately achieving therapeutic benefits in vivo.We report modified niosome-like surfactant vesicles,hereafter termed as NioTherms,formulated using a novel and simple heat-mix method,encapsulating PCZ for ocular administration in the form of an in situ gel.Excipient screening performed using in silico simulations highly correlate with in vitro studies(R^(2)=0.77),guiding optimization by Quality by Design(QbD)approach for encapsulating PCZ in NioTherms resulting in particles with an average size of 180.7±2.3 nm,zeta potential of +27.5±2.2 mV and entrapment efficiency of 87.6%±1.7%.A 2-fold increase in both mucin binding and cellular uptake indicates a functional role of positive surface charge in enhancingmucoadhesive properties of PCZ-NioTherms.In an in vivo murine ocular keratitis model,we demonstrate a 2-fold enhancement in trans-corneal permeability of PCZ-NioTherms and a 3-fold reduction in fungal burden compared to the control standard of care,the PCZ solution.Owing to a facile formulation process,we anticipate that PCZ-NioTherms would serve as a clinically translatable and patient compliant therapeutic intervention for treating FK.
基金supported by the National Natural Science Foundation of China(NSFC)(Nos.52202371 and 51902102)the Natural Science Foundation of Shandong Province(Nos.ZR202211230173,ZR2020QE066 and ZR2021QE200)+2 种基金the Opening Project of State Key Laboratory of Advanced Technology for Float Glass(No.2020KF08)the SDUT&Zibo City Integration Development Project(No.2021SNPT0045)the fellowship of China Postdoctoral Science Foundation(No.2020M672081).
文摘Transition metal carbonates(TMCs)hold great potential as high-performance electrodes for alkali metal-ion batteries,owing to multiple-ion storage mechanisms involving conversion process and electrocatalytic reaction.However,they still suffer from inferior electronic conductivity and volume variation during delithiation/lithiation.Heterostructure and heteroatoms doping offer immense promise in enhancing reaction kinetics and structural integrity,which unfortunately have not been achieved in TMCs.Herein,a unique TMCs heterostructure with Ni-doped MnCO_(3)as“core”and Mn-doped NiCO_(3)as“shell”,which is wrapped by graphene(NM@MN/RGO),is achieved by cations differentiation strategy.The formation process for core-shell NM@MN consists of epitaxial growth of NiCO_(3)from MnCO_(3)and synchronously mutual doping,owing to the similar crystal structures but different solubility product constant/formation energy of MnCO_(3)and NiCO_(3).In-situ electrochemical impedance spectroscopy,galvanostatic intermittent titration technique,differential capacity versus voltage plots,theoretical calculation and kinetic analysis reveal the superior electrochemical activity of the NM@MN/RGO to MnCO_(3)/RGO.The NM@MN/RGO shows excellent lithium storage properties(1013.4 mAh·g^(-1)at 0.1 A·g^(-1)and 760 mAh·g^(-1)after 1000 cycles at 2 A·g^(-1))and potassium storage properties(capacity decay rate of 0.114 mAh·g^(-1)per cycle).This work proposes an efficient cation differentiation strategy for constructing advanced TMC electrodes.
基金supported by the National Natural Science Foundation of China(U22A20429 and 22308103)Shanghai Pilot Program for Basic Research(22TQ1400100-13)+2 种基金Postdoctoral Fellowship Program of CPSF(GZB20230214)China Postdoctoral Science Foundation(2023M731083)the Fundamental Research Funds for the Central Universities.
文摘Developing cost-effective single-crystalline Ni-rich Co-poor cathodes operating at high-voltage is one of the most important ways to achieve higher energy Li-ion batteries. However, the Li/O loss and Li/Ni mixing under high-temperature lithiation result in electrochemical kinetic hysteresis and structural instability. Herein, we report a highly-ordered single-crystalline LiNi0.85Co0.05Mn0.10O2(NCM85) cathode by doping K+and F-ions. To be specific, the K-ion as a fluxing agent can remarkably decrease the solid-state lithiation temperature by ~30°C, leading to less Li/Ni mixing and oxygen vacancy. Meanwhile, the strong transitional metal(TM)-F bonds are helpful for enhancing de-/lithiation kinetics and limiting the lattice oxygen escape even at 4.5 V high-voltage. Their advantages synergistically endow the single-crystalline NCM85 cathode with a very high reversible capacity of 222.3 mAh g-1. A superior capacity retention of 91.3% is obtained after 500 times at 1 C in pouch-type full cells, and a prediction value of 75.3% is given after cycling for 5000 h. These findings are reckoned to expedite the exploitation and application of high-voltage single-crystalline Ni-rich cathodes for next-generation Li-ion batteries.
基金financially supported by the Key Fund Project of Tianjin Natural Science Foundation(24JCZDJC00510)the Fundamental Research Funds for the Central Universitiespartially supported by the U.S.Department of Energy under Contract No.DE-AC3608GO28308 with Alliance for Sustainable Energy,Limited Liability Company(LLC),the Manager and Operator of the National Renewable Energy Laboratory,through Grant No.DE-SC0020718。
文摘Incorporating organic bulky cations in the precursor or post-treatment to achieve two-dimensional/thr ee-dimensional(2D/3D)heterojunction is an effective strategy for enhancing the stability of perovskite materials.However,the issue of insufficient charge transport in 2D perovskites limits their development,and the fundamental mechanism of out-of-plane carrier transport remains unclear.This study designed and synthesized seven organic phenyl-core cations,differentiated at the 1-and 1,4-positions,and identified the impacts on the corresponding properties of the 2D crystalline perovskite.Shorter cations facilitated a more compact arrangement of adjacent inorganic layers,aligning to favor charge transport along the vertical direction.In addition,introducing high electronegativity led to increased intermolecular interactions,resulting in enhanced structural stability and improved phenyl ring π-orbital overlap and interlayer electron coupling,yielding efficient charge transport.Resilience to thermal stressing of the perovskite was strongly correlated with the carbon chain length of the spacer cations.The increase in cation length and the reduction in the rigidity of the amino-terminal both aided in the dispersion of thermal stress in the inorganic framework.Additional hydrogen bonding also contributed to mitigating structural disorder.
基金supported by the National Natural Science Foundation of China(Nos.21971080,22171098)supported by Chengdu Guibao Science&Technology Co.,Ltd.This work was also supported by the 111 Project(No.B17019)。
文摘The first-ever synthesis of the unknown furo[2,3:4,5]pyrimido[1,2-b]indazole skeleton was demonstrated based on the undiscovered tetra-functionalization of enaminones,with simple substrates and reaction conditions.The key to realizing this process lies in the multiple trapping of the in situ generated ketenimine cation by the 3-aminoindazole,which results in the formation of four new chemical bonds and two new rings in one pot.Moreover,the products of this new reaction were found to exhibit aggregationinduced emission(AIE)without modification.
基金supported by the Scientific Research and Technology Development Project of China National Petroleum Corporation(Grant Nos.2024ZG50,2022DQ03-03)the National Natural Science Foundation of China(Grant Nos.52372252)the Science and Technology Innovation Program of Hunan Province(Grant Nos.2024RC1022).
文摘Dendrite growth represents one of the most significant challenges that impede the development of aqueous zinc-ion batteries.Herein,Gd^(3+)ions are introduced into conventional electrolytes as a microlevelling agent to achieve dendrite-free zinc electrodeposition.Simulation and experimental results demonstrate that these Gd^(3+)ions are preferentially adsorbed onto the zinc surface,which enables dendritefree zinc anodes by activating the microlevelling effect during electrodeposition.In addition,the Gd^(3+)additives effectively inhibit side reactions and facilitate the desolvation of[Zn(H_(2)O)_(6)]^(2+),leading to highly reversible zinc plating/stripping.Due to these improvements,the zinc anode demonstrates a significantly prolonged cycle life of 2100 h and achieves an exceptional average Coulombic efficiency of 99.72%over 1400 cycles.More importantly,the Zn//NH_(4)V_(4)O_(10)full cell shows a high capacity retention rate of 85.6%after 1000 cycles.This work not only broadens the application of metallic cations in battery electrolytes but also provides fundamental insights into their working mechanisms.
基金supported by the Basic Science Research Program(RS-2024-00344021,RS-2023-00261543,and RS-202300257666)through the National Research Foundation of Korea(NRF),the National Research Council of Science(000)Korea Institute for Advancement of Technology(KIAT)grant funded by the Korea Government(MOTIE)(RS-2024-00420590,HRD Program for Industrial Innovation)The computational resources were provided by KITSI(KSC-2024-CRE-0143)。
文摘Despite the growing interest in fast-cha rging solid-state lithium(Li)-metal batteries(SSLMBs),their practical implementation has yet to be achieved,primarily due to an incomplete understanding of the disparate and often conflicting requirements of the bulk electrolyte and the electrode-electrolyte interphase.Here,we present a weakly coordinating cationic polymer electrolyte(WCPE)specifically designed to regulate the Li^(+)coordination structure,thereby enabling fast-charging SSLMBs.The WCPE comprises an imidazolium-based polycationic matrix combined with a succinonitrile(SN)-based highconcentration electrolyte.Unlike conventional neutral polymer matrices,the polycationic matrix in the WCPE competes with Li^(+)for interactions with SN,weakening the original coordination between SN and Li^(+).This modulation of SN-Li^(+)interaction improves both Li^(+)conductivity of the WCPE(σ_(Li^(+))=1.29mS cm^(-1))and redox kinetics at the electrode-electrolyte interphase.Consequently,SSLMB cells(comprising LiFePO_(4)cathodes and Li-metal anodes)with the WCPE achieve fast-charging capability(reaching over 80%state of charge within 10 min),outperforming those of previously reported polymer electrolytebased SSLMBs.
文摘Most of the international accreditation bodies in engineering education(e.g.,ABET)and outcome-based educational systems have based their assess-ments on learning outcomes and program educational objectives.However,map-ping program educational objectives(PEOs)to student outcomes(SOs)is a challenging and time-consuming task,especially for a new program which is applying for ABET-EAC(American Board for Engineering and Technology the American Board for Engineering and Technology—Engineering Accreditation Commission)accreditation.In addition,ABET needs to automatically ensure that the mapping(classification)is reasonable and correct.The classification also plays a vital role in the assessment of students’learning.Since the PEOs are expressed as short text,they do not contain enough semantic meaning and information,and consequently they suffer from high sparseness,multidimensionality and the curse of dimensionality.In this work,a novel associative short text classification tech-nique is proposed to map PEOs to SOs.The datasets are extracted from 152 self-study reports(SSRs)that were produced in operational settings in an engineering program accredited by ABET-EAC.The datasets are processed and transformed into a representational form appropriate for association rule mining.The extracted rules are utilized as delegate classifiers to map PEOs to SOs.The proposed asso-ciative classification of the mapping of PEOs to SOs has shown promising results,which can simplify the classification of short text and avoid many problems caused by enriching short text based on external resources that are not related or relevant to the dataset.
基金financially supported by the National Natural Science Foundation of China(No.52373011)。
文摘Living cationic polymerization of 4-acetoxystyrene(STO)was conducted in CH_(2)Cl_(2) at-15℃ using a dicumyl chloride(DCC)/SnCl_(4)/nBu_(4)NBr initiating system.Impurity moisture initiation was inhibited by adding proton trap 2,6-di-tert-butylpyridine(DTBP),and the controlled initiation of DCC was confirmed by ^(1)H nuclear magnetic resonance(^(1)H-NMR)spectroscopy and matrix-assisted laser desorption ionization time-offlight mass(MALDI-TOF-MS)spectrometry.The polymerization kinetics were analyzed to for optimizing the polymerization rate.Allyl-telechelic PSTOs(allyl-PSTO-allyl)with molecular weight(Mn)range of 3540–7800 g/mol and narrow molecular weight dispersity(Mw/Mn)about 1.25 were prepared through nucleophilic substitution with allyltrimethylsilane(ATMS)at approximately 40%monomer conversion.The experimental results indicate that the substitution efficiency of ATMS increased with higher ATMS concentration,temperature,and extended reaction time.Nearly unity ally-functionality for allyl-PSTO-allyl was achieved by adding sufficient SnCl_(4) prior to the substitution.
基金Project supported by the National Natural Science Foundation of China(22279025,21773048,52302119)the Fundamental Research Funds for the Central Universities(2023FRFK06005,HIT.NSRIF202204)。
文摘Cation segregation on cathode surfaces plays a key role in determining the activity and operational stability of solid oxide fuel cells(SOFCs).The double perovskite oxide PrBa_(0.8)Ca_(0.2)Co_(2)O_(5+δ)(PBCC)has been widely studied as an active cathode but still suffer from serious detrimental segregations.To enhance the cathode stability,a PBCC derived A-site medium-entropy Pr_(0.6)La_(0.1)Nd_(0.1)Sm_(0.1)Gd_(0.1)Ba_(0.8)Ca_(0.2)Co_(2)O_(5+δ)(ME-PBCC)oxide was prepared and its segregation behaviors were investigated under different conditions.Compared with initial PBCC oxide,the segregations of BaO and Co_(3)O_(4)on the surface of ME-PBCC material are significantly suppressed,especially for Co_(3)O_(4),which is attributed to its higher configuration entropy.Our results also confirm the improved electrochemical performance and structural stability of ME-PBCC material,enabling it as a promising cathode for SOFCs.