Fluoride-based electrolyte exhibits extraordinarily high oxidative stability in high-voltage lithium metal batteries(h-LMBs) due to the inherent low highest occupied molecular orbital(HOMO) of fiuorinated solvents. Ho...Fluoride-based electrolyte exhibits extraordinarily high oxidative stability in high-voltage lithium metal batteries(h-LMBs) due to the inherent low highest occupied molecular orbital(HOMO) of fiuorinated solvents. However, such fascinating properties do not bring long-term cyclability of h-LMBs. One of critical challenges is the interface instability in contacting with the Li metal anode, as fiuorinated solvents are highly susceptible to exceptionally reductive metallic Li attributed to its low lowest unoccupied molecular orbital(LUMO), which leads to significant consumption of the fiuorinated components upon cycling.Herein, attenuating reductive decomposition of fiuorinated electrolytes is proposed to circumvent rapid electrolyte consumption. Specifically, the vinylene carbonate(VC) is selected to tame the reduction decomposition by preferentially forming protective layer on the Li anode. This work, experimentally and computationally, demonstrates the importance of pre-passivation of Li metal anodes at high voltage to attenuate the decomposition of fiuoroethylene carbonate(FEC). It is expected to enrich the understanding of how VC attenuate the reactivity of FEC, thereby extending the cycle life of fiuorinated electrolytes in high-voltage Li-metal batteries.展开更多
This study explores the epistemic imperative to decolonize African education systems by centering indigenous philosophies such as Ubuntu and introducing the Ubuntu Pedagogy as a pedagogical model.Ubuntu pedagogy trans...This study explores the epistemic imperative to decolonize African education systems by centering indigenous philosophies such as Ubuntu and introducing the Ubuntu Pedagogy as a pedagogical model.Ubuntu pedagogy transforms teacher-learner relationships,it provides a replicable model for relational learning,community partnerships,and reassert the dignity of indigenous epistemologies.The paper examines how language,knowledge production,and pedagogy can be restructured to reflect African epistemologies and educational sovereignty.This research also explores the relationship between mother tongue instruction and cognitive access to learning.Through a qualitative literature analysis of case studies and African scholarly discourse,this paper highlights the continued marginalization of indigenous knowledge systems and the need to embed culturally relevant teaching methodologies.The findings support the broader question of whether there exists an epistemological base for knowledge independence or production within African and Afro-Diasporic contexts,revealing culturally coherent frameworks of learning that resist colonial dominance and an exploration of reclaiming African indigenous knowledge systems for educational and cultural sovereignty.展开更多
Strong multi-kilotesla magnetic fields have various applications in high-energy density science and laboratory astrophysics, but they are not readily available. In our previous work [Y. Shi et al., Phys. Rev. Lett. 13...Strong multi-kilotesla magnetic fields have various applications in high-energy density science and laboratory astrophysics, but they are not readily available. In our previous work [Y. Shi et al., Phys. Rev. Lett. 130, 155101(2023)], we developed a novel approach for generating such fields using multiple conventional laser beams with a twist in the pointing direction. This method is particularly well-suited for multi-kilojoule petawatt-class laser systems like SG-Ⅱ UP, which are designed with multiple linearly polarized beamlets. Utilizing three-dimensional kinetic particle-in-cell simulations, we examine critical factors for a proof-of-principle experiment, such as laser polarization, relative pulse delay,phase offset, pointing stability, and target configuration, and their impact on magnetic field generation. Our general conclusion is that the approach is very robust and can be realized under a wide range of laser parameters and plasma conditions. We also provide an in-depth analysis of the axial magnetic field configuration, azimuthal electron current, and electron and ion orbital angular momentum densities.Supported by a simple model, our analysis shows that the axial magnetic field decays owing to the expansion of hot electrons.展开更多
Fluorophores emitting in the second near-infrared window (NIR-II, 900–1700nm) allow for high-resolution deep-tissue bioimaging owing to minimal tissue scattering. Although J-aggregation offers a promising approach to...Fluorophores emitting in the second near-infrared window (NIR-II, 900–1700nm) allow for high-resolution deep-tissue bioimaging owing to minimal tissue scattering. Although J-aggregation offers a promising approach to developing long-wavelength emitters, the scarcity of J-type backbones and reliable design principles limits their application in biological imaging. Here, we introduce a strategy for engineering high-brightness NIR-II J-aggregated fluorophores by incorporating electron-withdrawing substituents into a fused-ring backbone. These substituents modulate the electrostatic potential (ESP) distribution across the conjugated backbone, reducing both electrostatic repulsion and intermolecular distance, which promotes ordered J-aggregation. As a result, Y8 aggregate (Y8 nanoparticles) exhibits an outstanding fluorescence quantum yield of up to 12.9% and strong near-infrared absorption in aqueous solution for high-performance NIR-II fluorescence imaging in vivo. This work not only presents a novel J-type backbone but also advances the understanding of the structure–property relationship critical to designing NIR-II J-aggregates.展开更多
Organic additives with multiple functional groups have shown great promise in improving the performance and stability of perovskite solar cells.The functional groups can passivate undercoordinated ions to reduce nonra...Organic additives with multiple functional groups have shown great promise in improving the performance and stability of perovskite solar cells.The functional groups can passivate undercoordinated ions to reduce nonradiative recombination losses.However,how these groups synergistically affect the enhancement beyond passivation is still unclear.Specifically,isomeric molecules with different substitution patterns or molecular shapes remain elusive in designing new organic additives.Here,we report two isomeric carbazolyl bisphosphonate additives,2,7-Cz BP and 3,6-Cz BP.The isomerism effect on passivation and charge transport process was studied.The two molecules have similar passivation effects through multiple interactions,e.g.,P=O···Pb,P=O···H–N and N–H···I.2,7-CzBP can further bridge the perovskite crystallites to facilitates charge transport.Power conversion efficiencies(PCEs)of 25.88%and 21.04%were achieved for 0.09 cm^(2)devices and 14 cm^(2)modules after 2,7-Cz BP treatment,respectively.The devices exhibited enhanced operational stability maintaining 95%of initial PCE after 1000 h of continuous maximum power point tracking.This study of isomerism effect hints at the importance of tuning substitution positions and molecular shapes for organic additives,which paves the way for innovation of next-generation multifunctional aromatic additives.展开更多
Neuroinflammation is the primary driver and signature of many neurodevelopmental disorders.However,because neurodevelopmental disorders caused by neuroinflammation are difficult to detect at the early stage,their prog...Neuroinflammation is the primary driver and signature of many neurodevelopmental disorders.However,because neurodevelopmental disorders caused by neuroinflammation are difficult to detect at the early stage,their progression remains unclear.To date,neither animal experiments nor in vitro models have uncovered their early developmental characteristics caused by neuroinflammation.In this study,we developed a neurovascular-unit-on-a-chip(NVU-on-a-chip)to model inflammation-induced neurodevelopmental disorders.With the chip,dynamic visualization of the progression caused by neuroinflammation was clearly demonstrated,and the changes in angiogenesis and neural differentiation under neuroinflammation were replicated.In addition,the activation of astrocytes and damage to neurons and capillaries at the early stage of neurodevelopmental disorders were observed.The results revealed for the first time the structural disruption of the neurovascular units and the neurovascular coupling failure caused by neuroinflammation.Furthermore,the outcomes of anti-inflammatory intervention using ibuprofen were preliminarily demonstrated.This work provides insights into the early progression of neurodevelopmental disorders caused by neuroinflammation and offers a platform for the development of therapeutic strategies for neuroinflammation.展开更多
Platinum group alloys have an excellent electronic structure for oxidation of alcohols,but the active sites are more susceptible to deactivation by CO adsorbates(CO_(ads)).The precise integration of single-atom and al...Platinum group alloys have an excellent electronic structure for oxidation of alcohols,but the active sites are more susceptible to deactivation by CO adsorbates(CO_(ads)).The precise integration of single-atom and alloy structures is highly attractive for energy conversion but still a challenge.Here,we report an ionexchange coupled in situ reduction strategy to fabricate hollow PtPdTe alloy nanoreactors loaded with atomically dispersed Cu sites(Cu_(SA)/h-PtPdTe NRs).The planted oxyphilic Cu single sites and resulted compressive strains are conductive to modulating the electronic structure of the active sites,which changes the rate-determining step of the reaction while inhibiting the formation of CO_(ads)and modulating the adsorption of intermediates,resulting in the improved activity and stability.Specifically,the obtained Cu_(SA)/h-PtPdTe NRs exhibit an excellent oxidation performance of multiple alcohols,especially for methanol and ethanol,with 8.0 and 10.3 times of the mass activity higher than Pt/C,and the activity could be recovered by refreshing the electrolyte and could be sustained for 72,000 and 36,000 s,respectively.Meanwhile,Cu_(SA)/h-PtPdTe NRs show superior oxidation performance and durability to ethylene glycol and glycerol.This work pioneers the realization of precise modulation of catalytic sites using single atoms and provides an encouraging pathway for the design of efficient and stable electrocatalysts for the oxidation of multiple alcohols,which could broaden the range of options and sources of fuel cells.展开更多
Lithium-ion batteries are essential for renewable energy storage,necessitating efficient battery management systems(BMS)for optimal performance and longevity.Accurate estimation of the state of health(SOH)is crucial f...Lithium-ion batteries are essential for renewable energy storage,necessitating efficient battery management systems(BMS)for optimal performance and longevity.Accurate estimation of the state of health(SOH)is crucial for BMS safety,yet current machine learning-based SOH estimation relying on global aging features often overlooks localized degradation patterns.In this study,we introduce a novel SOH estimation pipeline that integrates voltage-range-specific segmentation with a multi-stage,crossvalidation-driven localized feature-selection framework and a feature-augmented dual-stream fusion network.Our methodology partitions full-range voltage into localized intervals to construct a degradation-sensitive feature library,from which 4 optimal features are identified from a set of 336 candidates.These selected features are combined with raw voltage signals via a dual-stream architecture that employs a dynamic gating mechanism to recalibrate feature contributions during training.Crossvalidation-based evaluation on datasets encompassing different chemistries and charge/discharge protocols demonstrate that our approach can achieve lower average root-mean-square-error(Oxford dataset:0.7201%,Massachusetts Institute of Technology(MIT)dataset:0.7184%)compared to baseline models.An in-depth analysis of the physical significance of the screened features improves the interpretability of the features.This work underscores the significant potential of leveraging localized feature enhancement in SOH estimation by systematically integrating degradation-sensitive features,thereby offering precise estimation.展开更多
Atomically precise palladium(Pd)clusters are emerging as versatile nanomaterials with applications in catalysis and biomedicine.This study explores the synthesis,structure evolution,and catalytic properties of Pd clus...Atomically precise palladium(Pd)clusters are emerging as versatile nanomaterials with applications in catalysis and biomedicine.This study explores the synthesis,structure evolution,and catalytic properties of Pd clusters stabilized by cyclohexanethiol(HSC_(6)H_(11))ligands.Using electrospray ionization mass spectrometry(ESI-MS)and single-crystal X-ray diffraction(SXRD),structures of the Pd clusters ranging from Pd4(SC_(6)H_(11))8 to Pd18(SC_(6)H_(11))36 were determined.This analysis revealed a structure evolution from polygonal to elliptical geometries of the PdnS2n frameworks as the cluster size increased.UV-Vis-NIR spectroscopy,combined with quantum chemical calculations,elucidated changes in the electronic structure of the clusters.Catalytic studies on the Sonogashira cross-coupling reactions demonstrated a size-dependent decline in activity attributed to variations in structural arrangements and electronic properties.Mechanistic insights proposed a distinctive Pd(Ⅱ)-Pd(Ⅳ)catalytic cycle.This research underscores how ligands and cluster size influence the structures and properties of Pd clusters,offering valuable insights for the future design and application of Pd clusters in advanced catalysis and beyond.展开更多
Lead-tin(Pb-Sn)perovskites with an ideal bandgap of 1.34-1.40 eV show great promise in perovskite solar cells(PSCs).Recently,to address the environmental pollution and Sn^(2+)oxidation problems of dimethyl sulfoxide,m...Lead-tin(Pb-Sn)perovskites with an ideal bandgap of 1.34-1.40 eV show great promise in perovskite solar cells(PSCs).Recently,to address the environmental pollution and Sn^(2+)oxidation problems of dimethyl sulfoxide,methylammonium acetate(MAAc)ionic liquid has been developed as an alternative to fabricate ideal bandgap MAPb_(0.7)Sn_(0.3)I_(3)(1.36 eV)film via hot-casting in air.However,the spontaneous crystallization of Pb-Sn perovskite initiated by heat-induced supersaturation is fast and random,setting critical challenges in regulating crystal growth during the film-forming process.Herein,a lattice activation strategy is developed to control the crystallization dynamics of MAPb_(0.7)Sn_(0.3)I_(3)in MAAc to produce films with micrometer-sized grains in air.FA is shown to activate the crystal lattice that facilitates the formation of intermediates and balances the crystal growth of MAPb_(0.7)Sn_(0.3)I_(3),producing films with a grain size of 2.78±0.17μm.Furthermore,4-fluoro-phenethylammonium and phenethylammonium are adopted to passivate the defects in the film and promote the energy level alignment at the top interface,respectively.The optimized PSC device achieved an efficiency of 18.24%with a short-circuit current of 29.84 mA/cm^(2),which are both the highest values in 1.36 eV Pb-Sn PSCs to date.Notably,the unencapsulated devices show excellent storage and air stability under various conditions.展开更多
Excessive Fe^(3+) ion concentrations in wastewater pose a long-standing threat to human health.Achieving low-cost,high-efficiency quantification of Fe^(3+) ion concentration in unknown solutions can guide environmenta...Excessive Fe^(3+) ion concentrations in wastewater pose a long-standing threat to human health.Achieving low-cost,high-efficiency quantification of Fe^(3+) ion concentration in unknown solutions can guide environmental management decisions and optimize water treatment processes.In this study,by leveraging the rapid,real-time detection capabilities of nanopores and the specific chemical binding affinity of tannic acid to Fe^(3+),a linear relationship between the ion current and Fe^(3+) ion concentration was established.Utilizing this linear relationship,quantification of Fe^(3+) ion concentration in unknown solutions was achieved.Furthermore,ethylenediaminetetraacetic acid disodium salt was employed to displace Fe^(3+) from the nanopores,allowing them to be restored to their initial conditions and reused for Fe^(3+) ion quantification.The reusable bioinspired nanopores remain functional over 330 days of storage.This recycling capability and the long-term stability of the nanopores contribute to a significant reduction in costs.This study provides a strategy for the quantification of unknown Fe^(3+) concentration using nanopores,with potential applications in environmental assessment,health monitoring,and so forth.展开更多
The increasing severity of air pollution necessitates more effective and sustained air filtration technology.Concurrently,the desire for more environmentally friendly,sustainable materials with better filtering perfor...The increasing severity of air pollution necessitates more effective and sustained air filtration technology.Concurrently,the desire for more environmentally friendly,sustainable materials with better filtering performance and less environmental impact drives the move away from conventional synthetic membranes.This review presents lignocellulosic biocomposite(LigBioComp)membranes as an alternative to traditional synthetic membranes.It focuses on their materials,fabrication,and functionalization techniques while exploring challenges and proposing methods for resourceful utilization.Renowned for their abundance and renewable nature,lignocellulosic materials consist of cellulose,hemicellulose,and lignin.Various applications can benefit from their antibacterial properties,large surface area,and remarkable mechanical strength.LigBioComp membranes are fabricated through casting,electrospinning,and freeze-drying,with advancements in fabrication techniques enhancing their performance and applicability.It is suggested to use solvent-free or low-solvent techniques such as Layer-by-Layer assembly to minimize environmental impact.Freeze-drying and electrospinning with green solvents can be used for achieving specific membrane properties,though energy consumption should be considered.Apply dry-wet spinning and solvent casting processes selectively.Functional groups,including carboxyl,hydroxyl,or amino groups,can significantly improve the membrane’s capacity to capture particulate matter.Chemical etching or the precise deposition of nanoparticles can further optimize pore size and distribution.The choice of chemicals and methods is critical in functionalization,with silane coupling agents,polyethyleneimine,and polydopamine.Future research should prioritize refining fabrication methods,advancing functionalization strategies,and conducting performance and recyclability assessments on hybrid and composite materials.This will enhance integrated systems and contribute to the development of smart filters.展开更多
This paper presents the application of iterated function system (IFS) based three-dimensional (3D) fractal interpolation to elevation data compression. The parameters of contractive transformations are simplified by a...This paper presents the application of iterated function system (IFS) based three-dimensional (3D) fractal interpolation to elevation data compression. The parameters of contractive transformations are simplified by a concise fractal iteration form with geometric meaning. A local iteration algorithm is proposed, which can solve the non-separation problem when Collage theorem is applied to find the appropriate fractal parameters. The elevation data compression is proved experimentally to be effective in. reconstruction quality and time-saving.展开更多
Silicon/carbon composites,which integrate the high lithium storage performance of silicon with the exceptional mechanical strength and conductivity of carbon,will replace the traditional graphite electrodes for high-e...Silicon/carbon composites,which integrate the high lithium storage performance of silicon with the exceptional mechanical strength and conductivity of carbon,will replace the traditional graphite electrodes for high-energy lithium-ion batteries.Various strategies have been designed to synthesize silicon/carbon composites for tackling the issues of anode pulverization and poor stability in the anodes,thereby improving the lithium storage ability.The effect of the regulation method at each scale on the final negative electrode performance remains unclear.However,it has not been fully clarified how the regulation methods at each scale influence the final anode performance.This review will categorize the materials structure into three scales:molecular scale,nanoscale,and microscale.First,the review will examine modification methods at the molecular scale,focusing on the interfacial bonding force between silicon and carbon.Next,it will summarize various nanostructures and special shapes in the nanoscale to explore the construction of silicon/carbon composites.Lastly,the review will provide an analysis of microscale control approaches,focusing on the formation of composite particle with micron size and the utilization of micro-Si.This review provides a comprehensive overview of the multi-scale design of silicon/carbon composite anode materials and their optimization strategies to enhance the performance of lithium-ion batteries.展开更多
VS_(2) has attracted increasing attention as a cathode material for aqueous zinc ion batteries because of its proper large layer spacing,weak interlayer interactions,multiple valence states of V,and excellent electric...VS_(2) has attracted increasing attention as a cathode material for aqueous zinc ion batteries because of its proper large layer spacing,weak interlayer interactions,multiple valence states of V,and excellent electrical conductivity,but its large volume change during charging and discharging leads to poor cycling stability.Herein,we report a one-step hydrothermal synthesis of VS_(2) microflowers with proper lamellar spacing,which provides a stable framework for the insertion/deinsertion of zinc ions and enhances the cycling stability,delivering an initial charge capacity of 128.3 mAh g^(-1) at 3 A g^(-1) and maintains a charge capacity of 100.1 mAh g^(-1) after 900 cycles.In addition,the optimized VS_(2) cathode shows specific capacities of 215.7 and 150.5 mAh g^(-1) at the current densities of 0.1 and 2 A g^(-1),respectively,demonstrating that the microflower structure with a high specific surface area and a short diffusion distance also significantly enhances the rate performance.展开更多
Two-dimensional Ruddlesden-Popper(2DRP)perovskite exhibits excellent stability in perovskite solar cells(PSCs)due to introducing hydrophobic long-chain organic spacers.However,the poor charge transporting property of ...Two-dimensional Ruddlesden-Popper(2DRP)perovskite exhibits excellent stability in perovskite solar cells(PSCs)due to introducing hydrophobic long-chain organic spacers.However,the poor charge transporting property of bulky organic cation spacers limits the performance of 2DRP PSCs.Inspired by the Asite cation alloying strategy in 3D perovskites,2DRP perovskites with a binary spacer can promote charge transporting compared to the unary spacer counterparts.Herein,the superior MA-based 2DRP perovskite films with a binary spacer,including 3-guanidinopropanoic acid(GPA)and 4-fluorophenethylamine(FPEA)are realized.These films(GPA_(0.85)FPEA_(0.15))_(2)MA_(4)Pb_5I_(16)show good morphology,large grain size,decreased trap state density,and preferential orientation of the as-prepared film.Accordingly,the present 2DRP-based PSC with the binary spacer achieves a remarkable efficiency of 18.37%with a V_(OC)of1.15 V,a J_(SC)of 20.13 mA cm^(-2),and an FF of 79.23%.To our knowledge,the PCE value should be the highest for binary spacer MA-based 2DRP(n≤5)PSCs to date.Importantly,owing to the hydrophobic fluorine group of FPEA and the enhanced interlayer interaction by FPEA,the unencapsulated 2DRP PSCs based on binary spacers exhibit much excellent humidity stability and thermal stability than the unary spacer counterparts.展开更多
Cortical electrodes are a powerful tool for the stimulation and/or recording of electrical activity in the nervous system.However,the inevitable wound caused by surgical implantation of electrodes presents bacterial i...Cortical electrodes are a powerful tool for the stimulation and/or recording of electrical activity in the nervous system.However,the inevitable wound caused by surgical implantation of electrodes presents bacterial infection and inflammatory reaction risks associated with foreign body exposure.Moreover,inflammation of the wound area can dramatically worsen in response to bacterial infection.These consequences can not only lead to the failure of cortical electrode implantation but also threaten the lives of patients.Herein,we prepared a hydrogel made of bacterial cellulose(BC),a flexible substrate for cortical electrodes,and further loaded antibiotic tetracycline(TC)and the anti-inflammatory drug dexamethasone(DEX)onto it.The encapsulated drugs can be released from the BC hydrogel and effectively inhibit the growth of Gram-negative and Gram-positive bacteria.Next,therapeutic cortical electrodes were developed by integrating the drug-loaded BC hydrogel and nine-channel serpentine arrays;these were used to record electrocorticography(ECoG)signals in a rat model.Due to the controlled release of TC and DEX from the BC hydrogel substrate,therapeutic cortical electrodes can alleviate or prevent symptoms associated with the bacterial infection and inflammation of brain tissue.This approach facilitates the development of drug delivery electrodes for resolving complications caused by implantable electrodes.展开更多
With the aim of reducing the cost of developing internal combustion engines,while at the same time investigating different geometries,layouts and fuels,3D-CFD-CHT simulations represent an indispensable part for the de...With the aim of reducing the cost of developing internal combustion engines,while at the same time investigating different geometries,layouts and fuels,3D-CFD-CHT simulations represent an indispensable part for the development of new technologies.These tools are increasingly used by manufacturers,as a screening process before building the first prototype.This paper presents an innovative methodology for virtual engine development.The 3D-CFD tool QuickSim,developed at FKFS,allows both a significant reduction in computation time and an extension of the simulated domain for complete engine systems.This is possible thanks to a combination of coarse meshes and self-developed internal combustion engine models,which simultaneously ensure high predictability.The present work demonstrates the capabilities of this innovative methodology for the design and optimization of different engines and fuels with the goal of achieving the highest possible combustion efficiencies and pollutant reductions.The analysis focuses on the influence of different fuels such as hydrogen,methanol,synthetic gasolines and methane on different engine geometries,in combination with suitable injection and ignition systems,including passive and active pre-chambers.Lean operations as well as knock reduction are discussed,particularly for methane and hydrogen injection.Finally,it is shown how depending on the chosen fuel,an appropriate ad-hoc engine layout can be designed to increase the indicated efficiency of the respective engines.展开更多
基金The presented single-cylinder hydrogen engine study forms part of an international research project(FVV project No.1446)performed by the Institute of Automotive Engineering(IFS)at University of Stuttgart under the direction of Prof.AndréCasal Kulzer and by the Automotive Powertrain Technologies Group of Dr.Patrik Soltic at Swiss Federal Laboratories for Materials Science and Technology(EMPA)financially supported by Swiss Federal Office of Energy(SI/502205-01)FVV e.V.(funding No.6014462)。
基金supported by the National Natural Science Foundation of China (Nos. 22379121, 62005216)Basic Public Welfare Research Program of Zhejiang (No. LQ22F050013)+1 种基金Zhejiang Province Key Laboratory of Flexible Electronics Open Fund (2023FE005)Shenzhen Foundation Research Program (No. JCYJ20220530112812028)。
文摘Fluoride-based electrolyte exhibits extraordinarily high oxidative stability in high-voltage lithium metal batteries(h-LMBs) due to the inherent low highest occupied molecular orbital(HOMO) of fiuorinated solvents. However, such fascinating properties do not bring long-term cyclability of h-LMBs. One of critical challenges is the interface instability in contacting with the Li metal anode, as fiuorinated solvents are highly susceptible to exceptionally reductive metallic Li attributed to its low lowest unoccupied molecular orbital(LUMO), which leads to significant consumption of the fiuorinated components upon cycling.Herein, attenuating reductive decomposition of fiuorinated electrolytes is proposed to circumvent rapid electrolyte consumption. Specifically, the vinylene carbonate(VC) is selected to tame the reduction decomposition by preferentially forming protective layer on the Li anode. This work, experimentally and computationally, demonstrates the importance of pre-passivation of Li metal anodes at high voltage to attenuate the decomposition of fiuoroethylene carbonate(FEC). It is expected to enrich the understanding of how VC attenuate the reactivity of FEC, thereby extending the cycle life of fiuorinated electrolytes in high-voltage Li-metal batteries.
文摘This study explores the epistemic imperative to decolonize African education systems by centering indigenous philosophies such as Ubuntu and introducing the Ubuntu Pedagogy as a pedagogical model.Ubuntu pedagogy transforms teacher-learner relationships,it provides a replicable model for relational learning,community partnerships,and reassert the dignity of indigenous epistemologies.The paper examines how language,knowledge production,and pedagogy can be restructured to reflect African epistemologies and educational sovereignty.This research also explores the relationship between mother tongue instruction and cognitive access to learning.Through a qualitative literature analysis of case studies and African scholarly discourse,this paper highlights the continued marginalization of indigenous knowledge systems and the need to embed culturally relevant teaching methodologies.The findings support the broader question of whether there exists an epistemological base for knowledge independence or production within African and Afro-Diasporic contexts,revealing culturally coherent frameworks of learning that resist colonial dominance and an exploration of reclaiming African indigenous knowledge systems for educational and cultural sovereignty.
基金support by the National Natural Science Foundation of China(Grant No.12322513)USTC Research Funds of the Double First-Class Initiative+1 种基金CAS Project for Young Scientists in Basic Research(Grant No.YSBR060)supported by the Office of Fusion Energy Sciences under Award No.DE-SC0023423。
文摘Strong multi-kilotesla magnetic fields have various applications in high-energy density science and laboratory astrophysics, but they are not readily available. In our previous work [Y. Shi et al., Phys. Rev. Lett. 130, 155101(2023)], we developed a novel approach for generating such fields using multiple conventional laser beams with a twist in the pointing direction. This method is particularly well-suited for multi-kilojoule petawatt-class laser systems like SG-Ⅱ UP, which are designed with multiple linearly polarized beamlets. Utilizing three-dimensional kinetic particle-in-cell simulations, we examine critical factors for a proof-of-principle experiment, such as laser polarization, relative pulse delay,phase offset, pointing stability, and target configuration, and their impact on magnetic field generation. Our general conclusion is that the approach is very robust and can be realized under a wide range of laser parameters and plasma conditions. We also provide an in-depth analysis of the axial magnetic field configuration, azimuthal electron current, and electron and ion orbital angular momentum densities.Supported by a simple model, our analysis shows that the axial magnetic field decays owing to the expansion of hot electrons.
基金support from the National Natural Science Foundation of China (Nos. 62175201 and 52373142)the Natural Science Foundation of Jiangsu Province of China (No. BK20220404)+1 种基金the Fundamental Research Funds for the Central Universitiesthe open research fund of State Key Laboratory of Organic Electronics and Information Displays.
文摘Fluorophores emitting in the second near-infrared window (NIR-II, 900–1700nm) allow for high-resolution deep-tissue bioimaging owing to minimal tissue scattering. Although J-aggregation offers a promising approach to developing long-wavelength emitters, the scarcity of J-type backbones and reliable design principles limits their application in biological imaging. Here, we introduce a strategy for engineering high-brightness NIR-II J-aggregated fluorophores by incorporating electron-withdrawing substituents into a fused-ring backbone. These substituents modulate the electrostatic potential (ESP) distribution across the conjugated backbone, reducing both electrostatic repulsion and intermolecular distance, which promotes ordered J-aggregation. As a result, Y8 aggregate (Y8 nanoparticles) exhibits an outstanding fluorescence quantum yield of up to 12.9% and strong near-infrared absorption in aqueous solution for high-performance NIR-II fluorescence imaging in vivo. This work not only presents a novel J-type backbone but also advances the understanding of the structure–property relationship critical to designing NIR-II J-aggregates.
基金financially supported by the National Science Foundation of China(62474142)Natural Science Foundation of Shandong Province(No.ZR2024YQ070)。
文摘Organic additives with multiple functional groups have shown great promise in improving the performance and stability of perovskite solar cells.The functional groups can passivate undercoordinated ions to reduce nonradiative recombination losses.However,how these groups synergistically affect the enhancement beyond passivation is still unclear.Specifically,isomeric molecules with different substitution patterns or molecular shapes remain elusive in designing new organic additives.Here,we report two isomeric carbazolyl bisphosphonate additives,2,7-Cz BP and 3,6-Cz BP.The isomerism effect on passivation and charge transport process was studied.The two molecules have similar passivation effects through multiple interactions,e.g.,P=O···Pb,P=O···H–N and N–H···I.2,7-CzBP can further bridge the perovskite crystallites to facilitates charge transport.Power conversion efficiencies(PCEs)of 25.88%and 21.04%were achieved for 0.09 cm^(2)devices and 14 cm^(2)modules after 2,7-Cz BP treatment,respectively.The devices exhibited enhanced operational stability maintaining 95%of initial PCE after 1000 h of continuous maximum power point tracking.This study of isomerism effect hints at the importance of tuning substitution positions and molecular shapes for organic additives,which paves the way for innovation of next-generation multifunctional aromatic additives.
基金supported by the National Key R&D Program of China(No.2018AAA0100300)the National Natural Science Foundation of China(Nos.82072018,82274375,and 82402490)+5 种基金the Anhui Provincial Science and Technology Major Project(No.202203a07020006)the Strategic Priority Research Program(C)of the Chinese Academy of Sciences(CAS)(No.XDC07040200)the Key R&D Program of Anhui Province(No.2022e07020012)the Natural Science Foundation of Anhui Province(No.2208085QH256)the Fundamental Research Funds for the Central Universities(No.WK2100000042)the China Postdoctoral Science Foundation(No.2022M713055).
文摘Neuroinflammation is the primary driver and signature of many neurodevelopmental disorders.However,because neurodevelopmental disorders caused by neuroinflammation are difficult to detect at the early stage,their progression remains unclear.To date,neither animal experiments nor in vitro models have uncovered their early developmental characteristics caused by neuroinflammation.In this study,we developed a neurovascular-unit-on-a-chip(NVU-on-a-chip)to model inflammation-induced neurodevelopmental disorders.With the chip,dynamic visualization of the progression caused by neuroinflammation was clearly demonstrated,and the changes in angiogenesis and neural differentiation under neuroinflammation were replicated.In addition,the activation of astrocytes and damage to neurons and capillaries at the early stage of neurodevelopmental disorders were observed.The results revealed for the first time the structural disruption of the neurovascular units and the neurovascular coupling failure caused by neuroinflammation.Furthermore,the outcomes of anti-inflammatory intervention using ibuprofen were preliminarily demonstrated.This work provides insights into the early progression of neurodevelopmental disorders caused by neuroinflammation and offers a platform for the development of therapeutic strategies for neuroinflammation.
基金supported by the National Natural Science Foundation of China(22102132)the Funds for Basic Scientific Research in Central Universities+2 种基金the Scientific Research Foundation of Qingdao UniversityTaishan Scholar Program(NO.tsqnz20231213)sponsored by the Innovation Foundation for Doctor Dissertation of Northwestern Polytechnical University(CX2024101)。
文摘Platinum group alloys have an excellent electronic structure for oxidation of alcohols,but the active sites are more susceptible to deactivation by CO adsorbates(CO_(ads)).The precise integration of single-atom and alloy structures is highly attractive for energy conversion but still a challenge.Here,we report an ionexchange coupled in situ reduction strategy to fabricate hollow PtPdTe alloy nanoreactors loaded with atomically dispersed Cu sites(Cu_(SA)/h-PtPdTe NRs).The planted oxyphilic Cu single sites and resulted compressive strains are conductive to modulating the electronic structure of the active sites,which changes the rate-determining step of the reaction while inhibiting the formation of CO_(ads)and modulating the adsorption of intermediates,resulting in the improved activity and stability.Specifically,the obtained Cu_(SA)/h-PtPdTe NRs exhibit an excellent oxidation performance of multiple alcohols,especially for methanol and ethanol,with 8.0 and 10.3 times of the mass activity higher than Pt/C,and the activity could be recovered by refreshing the electrolyte and could be sustained for 72,000 and 36,000 s,respectively.Meanwhile,Cu_(SA)/h-PtPdTe NRs show superior oxidation performance and durability to ethylene glycol and glycerol.This work pioneers the realization of precise modulation of catalytic sites using single atoms and provides an encouraging pathway for the design of efficient and stable electrocatalysts for the oxidation of multiple alcohols,which could broaden the range of options and sources of fuel cells.
基金financially supported by the National Natural Science Foundation of China(22273096)the International Postdoctoral Exchange Fellowship Program between Helmholtz and OCPC(ZD2023019)+1 种基金the Young Scientists Fund of the National Natural Science Foundation of China(Grant No.22409139)the Sichuan Provincial Natural Science Foundation for Young Scientists(24NSFSC607)。
文摘Lithium-ion batteries are essential for renewable energy storage,necessitating efficient battery management systems(BMS)for optimal performance and longevity.Accurate estimation of the state of health(SOH)is crucial for BMS safety,yet current machine learning-based SOH estimation relying on global aging features often overlooks localized degradation patterns.In this study,we introduce a novel SOH estimation pipeline that integrates voltage-range-specific segmentation with a multi-stage,crossvalidation-driven localized feature-selection framework and a feature-augmented dual-stream fusion network.Our methodology partitions full-range voltage into localized intervals to construct a degradation-sensitive feature library,from which 4 optimal features are identified from a set of 336 candidates.These selected features are combined with raw voltage signals via a dual-stream architecture that employs a dynamic gating mechanism to recalibrate feature contributions during training.Crossvalidation-based evaluation on datasets encompassing different chemistries and charge/discharge protocols demonstrate that our approach can achieve lower average root-mean-square-error(Oxford dataset:0.7201%,Massachusetts Institute of Technology(MIT)dataset:0.7184%)compared to baseline models.An in-depth analysis of the physical significance of the screened features improves the interpretability of the features.This work underscores the significant potential of leveraging localized feature enhancement in SOH estimation by systematically integrating degradation-sensitive features,thereby offering precise estimation.
基金supported by the Start-Up Research Funding of Fujian Normal University(No.Y0720326K13)the National Natural Science Foundation of China(Nos.22103035 and 22033005)+2 种基金the National Key R&D Program of China(No.2022YFA1503900)Shenzhen Science and Technology Program(No.RCYX20231211090357078)Guangdong Provincial Key Laboratory of Catalysis(No.2020B121201002).
文摘Atomically precise palladium(Pd)clusters are emerging as versatile nanomaterials with applications in catalysis and biomedicine.This study explores the synthesis,structure evolution,and catalytic properties of Pd clusters stabilized by cyclohexanethiol(HSC_(6)H_(11))ligands.Using electrospray ionization mass spectrometry(ESI-MS)and single-crystal X-ray diffraction(SXRD),structures of the Pd clusters ranging from Pd4(SC_(6)H_(11))8 to Pd18(SC_(6)H_(11))36 were determined.This analysis revealed a structure evolution from polygonal to elliptical geometries of the PdnS2n frameworks as the cluster size increased.UV-Vis-NIR spectroscopy,combined with quantum chemical calculations,elucidated changes in the electronic structure of the clusters.Catalytic studies on the Sonogashira cross-coupling reactions demonstrated a size-dependent decline in activity attributed to variations in structural arrangements and electronic properties.Mechanistic insights proposed a distinctive Pd(Ⅱ)-Pd(Ⅳ)catalytic cycle.This research underscores how ligands and cluster size influence the structures and properties of Pd clusters,offering valuable insights for the future design and application of Pd clusters in advanced catalysis and beyond.
基金financially supported by the Natural Science Foundation of China(52372226,52202300,62288102,62350013,52303325)National Key Research and Development Program of China(2023YFB3608900)+5 种基金the Postdoctoral Fellowship Program ofthe China postdoctoral Science Foundation(CPSF)(Grant GZC20233506)the China Postdoctoral Science Foundation(Grant2024M764252)the Natural Science Foundation of Chongqing China(2023NSCQ-MSX0097)Guangdong Basic and Applied Basic Research Foundation(2024A1515010918)Shenzhen Science and Technology Program(Grant JCYJ20240813150819026)the Fundamental Research Funds for the Central Universities。
文摘Lead-tin(Pb-Sn)perovskites with an ideal bandgap of 1.34-1.40 eV show great promise in perovskite solar cells(PSCs).Recently,to address the environmental pollution and Sn^(2+)oxidation problems of dimethyl sulfoxide,methylammonium acetate(MAAc)ionic liquid has been developed as an alternative to fabricate ideal bandgap MAPb_(0.7)Sn_(0.3)I_(3)(1.36 eV)film via hot-casting in air.However,the spontaneous crystallization of Pb-Sn perovskite initiated by heat-induced supersaturation is fast and random,setting critical challenges in regulating crystal growth during the film-forming process.Herein,a lattice activation strategy is developed to control the crystallization dynamics of MAPb_(0.7)Sn_(0.3)I_(3)in MAAc to produce films with micrometer-sized grains in air.FA is shown to activate the crystal lattice that facilitates the formation of intermediates and balances the crystal growth of MAPb_(0.7)Sn_(0.3)I_(3),producing films with a grain size of 2.78±0.17μm.Furthermore,4-fluoro-phenethylammonium and phenethylammonium are adopted to passivate the defects in the film and promote the energy level alignment at the top interface,respectively.The optimized PSC device achieved an efficiency of 18.24%with a short-circuit current of 29.84 mA/cm^(2),which are both the highest values in 1.36 eV Pb-Sn PSCs to date.Notably,the unencapsulated devices show excellent storage and air stability under various conditions.
基金supported by the National Natural Science Foundation of China(Nos.52303380,52025132,52273305,22205185,21621091,22021001,and 22121001)Fundamental Research Funds for the Central Universities(No.20720240041)+3 种基金the 111 Project(Nos.B17027 and B16029)the National Science Foundation of Fujian Province of China(No.2022J02059)the Science and Technology Projects of Innovation Laboratory for Sciences and Technologies of Energy Materials of Fujian Province(No.RD2022070601)the New Cornerstone Science Foundation through the XPLORER PRIZE。
文摘Excessive Fe^(3+) ion concentrations in wastewater pose a long-standing threat to human health.Achieving low-cost,high-efficiency quantification of Fe^(3+) ion concentration in unknown solutions can guide environmental management decisions and optimize water treatment processes.In this study,by leveraging the rapid,real-time detection capabilities of nanopores and the specific chemical binding affinity of tannic acid to Fe^(3+),a linear relationship between the ion current and Fe^(3+) ion concentration was established.Utilizing this linear relationship,quantification of Fe^(3+) ion concentration in unknown solutions was achieved.Furthermore,ethylenediaminetetraacetic acid disodium salt was employed to displace Fe^(3+) from the nanopores,allowing them to be restored to their initial conditions and reused for Fe^(3+) ion quantification.The reusable bioinspired nanopores remain functional over 330 days of storage.This recycling capability and the long-term stability of the nanopores contribute to a significant reduction in costs.This study provides a strategy for the quantification of unknown Fe^(3+) concentration using nanopores,with potential applications in environmental assessment,health monitoring,and so forth.
基金funded by the Universiti Teknologi Malaysia(UTM)through research Grant Number:06E05.
文摘The increasing severity of air pollution necessitates more effective and sustained air filtration technology.Concurrently,the desire for more environmentally friendly,sustainable materials with better filtering performance and less environmental impact drives the move away from conventional synthetic membranes.This review presents lignocellulosic biocomposite(LigBioComp)membranes as an alternative to traditional synthetic membranes.It focuses on their materials,fabrication,and functionalization techniques while exploring challenges and proposing methods for resourceful utilization.Renowned for their abundance and renewable nature,lignocellulosic materials consist of cellulose,hemicellulose,and lignin.Various applications can benefit from their antibacterial properties,large surface area,and remarkable mechanical strength.LigBioComp membranes are fabricated through casting,electrospinning,and freeze-drying,with advancements in fabrication techniques enhancing their performance and applicability.It is suggested to use solvent-free or low-solvent techniques such as Layer-by-Layer assembly to minimize environmental impact.Freeze-drying and electrospinning with green solvents can be used for achieving specific membrane properties,though energy consumption should be considered.Apply dry-wet spinning and solvent casting processes selectively.Functional groups,including carboxyl,hydroxyl,or amino groups,can significantly improve the membrane’s capacity to capture particulate matter.Chemical etching or the precise deposition of nanoparticles can further optimize pore size and distribution.The choice of chemicals and methods is critical in functionalization,with silane coupling agents,polyethyleneimine,and polydopamine.Future research should prioritize refining fabrication methods,advancing functionalization strategies,and conducting performance and recyclability assessments on hybrid and composite materials.This will enhance integrated systems and contribute to the development of smart filters.
文摘This paper presents the application of iterated function system (IFS) based three-dimensional (3D) fractal interpolation to elevation data compression. The parameters of contractive transformations are simplified by a concise fractal iteration form with geometric meaning. A local iteration algorithm is proposed, which can solve the non-separation problem when Collage theorem is applied to find the appropriate fractal parameters. The elevation data compression is proved experimentally to be effective in. reconstruction quality and time-saving.
基金funded by the Research Fund of State Key Laboratory of Mesoscience and Engineering (MESO-23-T03)the National Natural Science Foundation (22278423)+1 种基金the National Key Research and Development Program of China (2022YFB3805602)the Science Foundation of China University of Petroleum,Beijing (2462021QNXZ007)。
文摘Silicon/carbon composites,which integrate the high lithium storage performance of silicon with the exceptional mechanical strength and conductivity of carbon,will replace the traditional graphite electrodes for high-energy lithium-ion batteries.Various strategies have been designed to synthesize silicon/carbon composites for tackling the issues of anode pulverization and poor stability in the anodes,thereby improving the lithium storage ability.The effect of the regulation method at each scale on the final negative electrode performance remains unclear.However,it has not been fully clarified how the regulation methods at each scale influence the final anode performance.This review will categorize the materials structure into three scales:molecular scale,nanoscale,and microscale.First,the review will examine modification methods at the molecular scale,focusing on the interfacial bonding force between silicon and carbon.Next,it will summarize various nanostructures and special shapes in the nanoscale to explore the construction of silicon/carbon composites.Lastly,the review will provide an analysis of microscale control approaches,focusing on the formation of composite particle with micron size and the utilization of micro-Si.This review provides a comprehensive overview of the multi-scale design of silicon/carbon composite anode materials and their optimization strategies to enhance the performance of lithium-ion batteries.
基金financially supported by the Ningbo Natural Science Foundation(No.202003N4054)the Fundamental Research Funds for the Central Universities.
文摘VS_(2) has attracted increasing attention as a cathode material for aqueous zinc ion batteries because of its proper large layer spacing,weak interlayer interactions,multiple valence states of V,and excellent electrical conductivity,but its large volume change during charging and discharging leads to poor cycling stability.Herein,we report a one-step hydrothermal synthesis of VS_(2) microflowers with proper lamellar spacing,which provides a stable framework for the insertion/deinsertion of zinc ions and enhances the cycling stability,delivering an initial charge capacity of 128.3 mAh g^(-1) at 3 A g^(-1) and maintains a charge capacity of 100.1 mAh g^(-1) after 900 cycles.In addition,the optimized VS_(2) cathode shows specific capacities of 215.7 and 150.5 mAh g^(-1) at the current densities of 0.1 and 2 A g^(-1),respectively,demonstrating that the microflower structure with a high specific surface area and a short diffusion distance also significantly enhances the rate performance.
基金financially supported by the Natural Science Foundation of China(Grant Nos.52372226,52173263,62004167)the Natural Science Basic Research Plan in Shaanxi Province of China(Grant Nos.2022JM-315,2023-JC-QN-0643)+4 种基金the National Key R&D Program of China(Grant No.2022YFB3603703)the Qinchuangyuan High-level Talent Project of Shaanxi(Grant No.QCYRCXM-2022-219)the Ningbo Natural Science Foundation(Grant No.2022J061)the Key Research and Development Program of Shaanxi(Grant No.2023GXLH-091)the Shccig-Qinling Program and the Fundamental Research Funds for the Central Universities。
文摘Two-dimensional Ruddlesden-Popper(2DRP)perovskite exhibits excellent stability in perovskite solar cells(PSCs)due to introducing hydrophobic long-chain organic spacers.However,the poor charge transporting property of bulky organic cation spacers limits the performance of 2DRP PSCs.Inspired by the Asite cation alloying strategy in 3D perovskites,2DRP perovskites with a binary spacer can promote charge transporting compared to the unary spacer counterparts.Herein,the superior MA-based 2DRP perovskite films with a binary spacer,including 3-guanidinopropanoic acid(GPA)and 4-fluorophenethylamine(FPEA)are realized.These films(GPA_(0.85)FPEA_(0.15))_(2)MA_(4)Pb_5I_(16)show good morphology,large grain size,decreased trap state density,and preferential orientation of the as-prepared film.Accordingly,the present 2DRP-based PSC with the binary spacer achieves a remarkable efficiency of 18.37%with a V_(OC)of1.15 V,a J_(SC)of 20.13 mA cm^(-2),and an FF of 79.23%.To our knowledge,the PCE value should be the highest for binary spacer MA-based 2DRP(n≤5)PSCs to date.Importantly,owing to the hydrophobic fluorine group of FPEA and the enhanced interlayer interaction by FPEA,the unencapsulated 2DRP PSCs based on binary spacers exhibit much excellent humidity stability and thermal stability than the unary spacer counterparts.
基金support from the National Natural Science Foundation of China(Nos.52073230,62204204,and 62288102)the Shaanxi Provincial Science Fund for Distinguished Young Scholars(No.2023-JC-JQ-32)+2 种基金the Science and Technology Innovation 2030-Major Project(No.2022ZD0208601)the Shanghai Sailing Program(No.21YF1451000)the China National Postdoctoral Program for Innovative Talents(No.BX20230494).
文摘Cortical electrodes are a powerful tool for the stimulation and/or recording of electrical activity in the nervous system.However,the inevitable wound caused by surgical implantation of electrodes presents bacterial infection and inflammatory reaction risks associated with foreign body exposure.Moreover,inflammation of the wound area can dramatically worsen in response to bacterial infection.These consequences can not only lead to the failure of cortical electrode implantation but also threaten the lives of patients.Herein,we prepared a hydrogel made of bacterial cellulose(BC),a flexible substrate for cortical electrodes,and further loaded antibiotic tetracycline(TC)and the anti-inflammatory drug dexamethasone(DEX)onto it.The encapsulated drugs can be released from the BC hydrogel and effectively inhibit the growth of Gram-negative and Gram-positive bacteria.Next,therapeutic cortical electrodes were developed by integrating the drug-loaded BC hydrogel and nine-channel serpentine arrays;these were used to record electrocorticography(ECoG)signals in a rat model.Due to the controlled release of TC and DEX from the BC hydrogel substrate,therapeutic cortical electrodes can alleviate or prevent symptoms associated with the bacterial infection and inflammation of brain tissue.This approach facilitates the development of drug delivery electrodes for resolving complications caused by implantable electrodes.
文摘With the aim of reducing the cost of developing internal combustion engines,while at the same time investigating different geometries,layouts and fuels,3D-CFD-CHT simulations represent an indispensable part for the development of new technologies.These tools are increasingly used by manufacturers,as a screening process before building the first prototype.This paper presents an innovative methodology for virtual engine development.The 3D-CFD tool QuickSim,developed at FKFS,allows both a significant reduction in computation time and an extension of the simulated domain for complete engine systems.This is possible thanks to a combination of coarse meshes and self-developed internal combustion engine models,which simultaneously ensure high predictability.The present work demonstrates the capabilities of this innovative methodology for the design and optimization of different engines and fuels with the goal of achieving the highest possible combustion efficiencies and pollutant reductions.The analysis focuses on the influence of different fuels such as hydrogen,methanol,synthetic gasolines and methane on different engine geometries,in combination with suitable injection and ignition systems,including passive and active pre-chambers.Lean operations as well as knock reduction are discussed,particularly for methane and hydrogen injection.Finally,it is shown how depending on the chosen fuel,an appropriate ad-hoc engine layout can be designed to increase the indicated efficiency of the respective engines.
