Large-area graphene films with defined uniformity,thickness and morphology are crucial for their applications in optoelectronic and photothermal devices.Herein,we demonstrate that oriented arrangement and ordered asse...Large-area graphene films with defined uniformity,thickness and morphology are crucial for their applications in optoelectronic and photothermal devices.Herein,we demonstrate that oriented arrangement and ordered assembly of graphene oxide(GO)nanosheets in solution films can be realized to obtain the high-quality and large-area reduced GO(rGO)films.The key to the success of this process primarily lies in the control of GO solution shear force direction with array capillaries,achieving oriented arrangement of GO nanosheets in the solution film.Secondly,the control of GO nanosheet concentration and solution viscosity during solvent evaporation of solution film is key to achieve the ordered and disordered assembly of GO,featuring the smooth and wrinkled structure rGO films,respectively.Subsequently,the resultant smooth rGO film with ordered assembly exhibits excellent thermal conductivity and electronic conductivity(over 1800 S·cm-1).Meanwhile,the wrinkled rGO film with disordered assembly can be used as a coating layer on Al current collectors,demonstrating anticorrosion properties and enhanced material adhesive stability.As a result,with such collectors,the high-voltage Li//NCM811 batteries show a 6-fold increase in cycle stability,and the lithium-sulfur batteries with high sulfur loading show a 3-fold increase in cycle stability.展开更多
Peroxymonosulfate(PMS)-assisted visible-light photocatalytic degradation of organic pollutants using graphitic carbon nitride(g-C_(3)N_(4))presents a promising and environmentally friendly approach.However,pristine g-...Peroxymonosulfate(PMS)-assisted visible-light photocatalytic degradation of organic pollutants using graphitic carbon nitride(g-C_(3)N_(4))presents a promising and environmentally friendly approach.However,pristine g-C_(3)N_(4) suffers from limited visible-light absorption and low charge-carrier mobility.In this study,a phosphorus-doped tubular carbon nitride(5P-TCN)was synthesized via a precursor self-assembly method using phosphoric acid and melamine as raw materials,eliminating the need for organic solvents or templates.The 5P-TCN catalyst demonstrated enhanced visible-light absorption,improved charge transfer capability,and a 5.25-fold increase in specific surface area(31.092 m^(2)/g),which provided abundant active sites to efficiently drive the PMS-assisted photocatalytic reaction.The 5P-TCN/vis/PMS system exhibited exceptional degradation performance for organic pollutants across a broad pH range(3–9),achieving over 92%degradation of Rhodamine B(RhB)within 15 min.Notably,the system retained>98%RhB degradation efficiency after three consecutive operational cycles,demonstrating robust operational stability and reusability.Moreover,key parameters influencing,active radi-cals,degradation pathways,and potential mechanisms for RhB degradation were systematically investigated.This work proposes a green and cost-effective strategy for developing high-efficiency photocatalysts,while demon-strating the exceptional capability of a PMS-assisted photocatalytic system for rapid degradation of RhB.展开更多
Recently,hollow carbon nanospheres(HCSs)have garnered significant attention as potential Li metal hosts owing to their unique large voids and ease of fabrication.However,similar to other nanoscale hosts,their practica...Recently,hollow carbon nanospheres(HCSs)have garnered significant attention as potential Li metal hosts owing to their unique large voids and ease of fabrication.However,similar to other nanoscale hosts,their practical performance is limited by inhomogeneous agglomeration,increased binder requirements,and high tortuosity within the electrode.To overcome these problems and high tortuosity within the electrode,this study introduces a pomegranate-like carbon microcluster composed of primary HCSs(P-CMs)as a novel Li metal host.This unique nanostructure can be easily prepared using the spray-drying technique,enabling its mass production.Comprehensive analyses with various tools demonstrate that compared with HCS hosts,the P-CM host requires a smaller amount of binder to fabricate a sufficiently robust and even surface electrode.Furthermore,owing to reduced tortuosity,the well-designed P-CM electrode can provide continuous and shortened pathways for electron/ion transport,accelerating the Li-ion transfer kinetics and prohibiting preferential Li plating at the upper region of the electrode.Due to these characteristics,Li metal can be effectively encapsulated in the large inner voids of the primary HCSs constituting the P-CM,thereby enhancing the electrochemical performance of P-CM hosts in Li metal batteries.Specifically,the Coulombic efficiency of the P-CM host can be maintained at 97%over 100 cycles,with a high Li deposition areal capacity of 3 mAh·cm^(-2)and long cycle life(1000 h,1 mA·cm^(-2),and 1.0 mAh·cm^(-2)).Furthermore,a full cell incorporating a LiFePO4 cathode exhibits excellent cycle life.展开更多
Four glycoluril-based amphiphilic molecular clips(AMCs)M1~M4 have been prepared for intracellular delivery of short DNA.M1~M4 have two methyl groups on its convex surface and four cations on its aromatic side arm,whic...Four glycoluril-based amphiphilic molecular clips(AMCs)M1~M4 have been prepared for intracellular delivery of short DNA.M1~M4 have two methyl groups on its convex surface and four cations on its aromatic side arm,which can be used to construct self-assembled nanoparticles in aqueous solution driven by hydrophobic interaction.Dynamic light scattering experiments show that M1 and M2 can be driven hydrophobically to aggregate into extremely stable nanoparticles in water at the micromolar concentrations.Fluorescence titration and zeta potential experiments support that the nanoparticles formed by M1 and M2 are able to efficiently encapsulate short DNA(sDNA).Fluorescence imaging and flow cytometry studies reveal that their nano sizes enable intracellular delivery of the encapsulated sDNA into both normal and cancer cells,with delivery percentage reaching up to 94%,while in vitro experiments indicate that the two compounds have excellent biocompatibility and low cytotoxicity.展开更多
We report on the measurement of shear viscosity in an ultracold Fermi gas with variable temperatures and tunable interactions.A quadrupole mode excitation in an isotropic harmonic trap is used to quantify the shear vi...We report on the measurement of shear viscosity in an ultracold Fermi gas with variable temperatures and tunable interactions.A quadrupole mode excitation in an isotropic harmonic trap is used to quantify the shear viscosity of the quantum gas within the hydrodynamic regime.The shear viscosity of the system as a function of temperature has been investigated,and the results closely align with calculations in the high-temperature limit utilizing a new definition of the cutoff radius.Through an adiabatic sweep across the Bardeen–Cooper–Schrieffer(BCS)to Bose–Einstein condensate(BEC)crossover,we find that the minimum value of the shear viscosity,as a function of interaction strength,is significantly shifted toward the BEC side.Furthermore,the behavior of the shear viscosity is asymmetric on both sides of the location of the minimum.展开更多
A predictive model of meiotic crossover engineering would increase precision in crop breeding.We review the biological principles underlying crossover formation and chromosomal distribution,hierarchical control mechan...A predictive model of meiotic crossover engineering would increase precision in crop breeding.We review the biological principles underlying crossover formation and chromosomal distribution,hierarchical control mechanisms enforcing crossover assurance,and an emerging phase-separation model determining crossover interference patterning.展开更多
Thermoelectric materials,capable of converting temperature gradients into electrical power,have been traditionally limited by a trade-off between thermopower and electrical conductivity.This study introduces a novel,b...Thermoelectric materials,capable of converting temperature gradients into electrical power,have been traditionally limited by a trade-off between thermopower and electrical conductivity.This study introduces a novel,broadly applicable approach that enhances both the spin-driven thermopower and the thermoelectric figure-of-merit(zT)without compromising electrical conductivity,using temperature-driven spin crossover.Our approach,supported by both theoretical and experimental evidence,is demonstrated through a case study of chromium doped-manganese telluride,but is not confined to this material and can be extended to other magnetic materials.By introducing dopants to create a high crystal field and exploiting the entropy changes associated with temperature-driven spin crossover,we achieved a significant increase in thermopower,by approximately 136μV K^(-1),representing more than a 200%enhancement at elevated temperatures within the paramagnetic domain.Our exploration of the bipolar semiconducting nature of these materials reveals that suppressing bipolar magnon/paramagnon-drag thermopower is key to understanding and utilizing spin crossover-driven thermopower.These findings,validated by inelastic neutron scattering,X-ray photoemission spectroscopy,thermal transport,and energy conversion measurements,shed light on crucial material design parameters.We provide a comprehensive framework that analyzes the interplay between spin entropy,hopping transport,and magnon/paramagnon lifetimes,paving the way for the development of high-performance spin-driven thermoelectric materials.展开更多
The interplay between dimensionality and superconductivity is a central theme in understanding the behavior of low-dimensional superconductors. In this work, we investigate the dimensional crossover from quasi-two-dim...The interplay between dimensionality and superconductivity is a central theme in understanding the behavior of low-dimensional superconductors. In this work, we investigate the dimensional crossover from quasi-two-dimensional(quasi-2D) to three-dimensional(3D) superconductivity in(Li,Fe)OHFeSe_(1-x)S_(x) single crystals driven by sulfur doping.Through detailed structural, electrical, and magnetic characterization, we identify a critical doping level(x = 0.53) where the system transitions from quasi-2D to 3D superconducting behavior. Reduced superconducting fluctuations and nonFermi liquid behavior near this critical point suggest the presence of competition between intralayer and interlayer pairing mechanisms. Fluctuation conductivity analysis reveals that the coherence length along the c-axis, ζ_(c)(0), and the interlayer coupling strength, Γ, increase significantly at x = 0.53, marking the onset of 3D superconductivity. These findings provide new insights into the role of dimensionality and interlayer coupling in modulating superconducting properties, positioning(Li,Fe)OHFeSe_(1-x)S_(x) as a unique platform for exploring crossover physics in iron-based superconductors.展开更多
Nowadays,high-stable and ultrasensitive heavy metal detection is of utmost importance in water quality monitoring.Nanoparticle-enhanced laser-induced breakdown spectroscopy(NELIBS)shows high potential in hazardous met...Nowadays,high-stable and ultrasensitive heavy metal detection is of utmost importance in water quality monitoring.Nanoparticle-enhanced laser-induced breakdown spectroscopy(NELIBS)shows high potential in hazardous metal detection,however,encounters unstable and weak signals due to nonuniform distribution of analytes.Herein,we developed an interface self-assembly(ISA)method to create a uniformly distributed gold nanolayer at a liquid-liquid interface for positive heavy metal ions capture and NELIBS analysis.The electrostatically selfassembled Au nanoparticles(NPs)-analytes membrane was prepared at the oil-water interface by injecting ethanol into the mixture of cyclohexane and Au NPs-analytes water solution.Then,the interface self-assembled Au NPs-analytes membrane was transformed onto a laser-processed superhydrophilic Si slide for detection.Three heavy metals(cadmium(Cd),barium(Ba),and chromium(Cr))were analyzed to evaluate the stability and sensitivity of the ISA method for NELIBS.The results(Cd:RSD=3.6%,LoD=0.654 mg/L;Ba:RSD=3.4%,LoD=0.236 mg/L;Cr:RSD=7.7%,LoD=1.367 mg/L)demonstrated signal enhancement and high-stable and ultrasensitive detection.The actual sample detection(Cd:RE=7.71%,Ba:RE=6.78%)illustrated great reliability.The ISA method,creating a uniform distribution of NP-analytes at the interface,has promising prospects in NELIBS.展开更多
Diphenylalanine and its analogs cause many concerns owing to their perfect self-assembly properties in the fields of biology,medicine,and nanotechnology.Experimental research has shown that diphenylalanine-based analo...Diphenylalanine and its analogs cause many concerns owing to their perfect self-assembly properties in the fields of biology,medicine,and nanotechnology.Experimental research has shown that diphenylalanine-based analogs with ethylenediamine linkers(PA,P=phenylalanine,and A=analog)can self-assemble into spherical assemblies,which can serve as novel anticancer drug carriers.In this work,to understand the assembly pathways,drug loading behavior,and formation mechanism of PA aggregates at the molecular level,we carried out dissipative particle dynamics(DPD)simulations of PA molecule systems.Our simulation results demonstrate that PA molecules spontaneously assemble into nanospheres and can self-assemble into drug-loaded nanospheres upon addition of the cancer chemotherapeutic agent doxorubicin(DOX).We also found that the hydrophobic side chain beads of PA molecules exhibited a unique onion-like distribution inside the nanospheres,which was not observed in the experiment.The onion-like nanospheres were verified by calculating the radial distribution function(RDF)of the DPD beads.Furthermore,based on the analysis of the percentages of different interaction components in the total nonbonded energies,main chain-side chain interactions between PA molecules may be important in the formation of onion-like nanospheres,and the synergistic effects of main chain-side chain,main chain-drug,side chain-drug,and main chain-solvent interactions are significant in the formation of drug-loaded nanospheres.These findings provide new insights into the structure and self-assembly pathway of PA assemblies,which may be helpful for the design of efficient and effective drug delivery systems.展开更多
In order to maximize the advantages of high energy density in Li metal batteries,it is necessary to match cathode materials with high specific capacities.Ni-rich layered oxides have been shown to reversibly embed more...In order to maximize the advantages of high energy density in Li metal batteries,it is necessary to match cathode materials with high specific capacities.Ni-rich layered oxides have been shown to reversibly embed more Li+during charge and discharge processes due to the increased Ni content in their crystal structure,thereby providing higher energy density.However,a significant challenge associated with Ni-rich layered oxide cathodes is the crossover effect,which arises from the dissolution of Ni^(2+)from the cathode,leading to a rapid decline in battery capacity.Through the delocalization-induced effect of solvent molecules,Ni^(2+)is transformed into a fluorinated transition metal inorganic phase layer,thereby forming a corrosion-resistant Li metal interface.This prevents solvent molecules from being reduced and degraded by Li metal anode.The surface of the Li metal anode exhibits a smooth and flat deposition morphology after long-term cycling.Furthermore,the introduction of Ni^(2+)can enhance the concentration gradient of transition metal ions near the cathode,thereby suppressing the dissolution process of transition metal ions.Even the NCM955 cathode with a mass load of 22 mg cm^(−2)also has great capacity retention after cycling.The Ni^(2+)induced by high electronegative functional groups of solvent under the electron delocalization effect,preventing the Ni ions dissolution of cathode and constructing a corrosion-resistant Li metal interface layer.This work provides new insights into suppressing crossover effects in Li metal batteries with high nickel cathodes.展开更多
The potential of metal nanoclusters in biomedical applications is limited due to aggregation-caused quenching(ACQ).In this study,an in situ self-assembled pitaya structure was proposed to obtain stable fluorescence em...The potential of metal nanoclusters in biomedical applications is limited due to aggregation-caused quenching(ACQ).In this study,an in situ self-assembled pitaya structure was proposed to obtain stable fluorescence emission through protein coronas-controlled distance between gold nanoclusters(Au NCs).Interestingly,the gold ion complexes coated with proteins of low isoelectric point(pI)nucleate at the secondary structure of proteins with high p I through ionic exchange within cells,generating fluorescent Au NCs.It is worth noting that due to the steric hindrance formed by the protein coronas on the surface of Au NCs,the distance between Au NCs can be controlled,avoiding electron transfer caused by close proximity of Au NCs and inhibiting fluorescence ACQ.This strategy can achieve fluorescence imaging of clinical tissue samples without observable side effects.Therefore,this study proposes a distance-controllable self-assembled pitaya structure to provide a new approach for Au NCs with stable fluorescence.展开更多
This study introduces a novel mathematical model to describe the progression of cholera by integrating fractional derivatives with both singular and non-singular kernels alongside stochastic differential equations ove...This study introduces a novel mathematical model to describe the progression of cholera by integrating fractional derivatives with both singular and non-singular kernels alongside stochastic differential equations over four distinct time intervals.The model incorporates three key fractional derivatives:the Caputo-Fabrizio fractional derivative with a non-singular kernel,the Caputo proportional constant fractional derivative with a singular kernel,and the Atangana-Baleanu fractional derivative with a non-singular kernel.We analyze the stability of the core model and apply various numerical methods to approximate the proposed crossover model.To achieve this,the approximation of Caputo proportional constant fractional derivative with Grünwald-Letnikov nonstandard finite difference method is used for the deterministic model with a singular kernel,while the Toufik-Atangana method is employed for models involving a non-singular Mittag-Leffler kernel.Additionally,the integral Caputo-Fabrizio approximation and a two-step Lagrange polynomial are utilized to approximate the model with a non-singular exponential decay kernel.For the stochastic component,the Milstein method is implemented to approximate the stochastic differential equations.The stability and effectiveness of the proposed model and methodologies are validated through numerical simulations and comparisons with real-world cholera data from Yemen.The results confirm the reliability and practical applicability of the model,providing strong theoretical and empirical support for the approach.展开更多
The development of new and efficient extractants plays a key role in the separation and recovery of rare earth elements.In this pape r,the extractant(N,N-methyl py ridineethyl-N',N'-dicyclohexyl-3-oxadiglycola...The development of new and efficient extractants plays a key role in the separation and recovery of rare earth elements.In this pape r,the extractant(N,N-methyl py ridineethyl-N',N'-dicyclohexyl-3-oxadiglycolamide,MPyEDChDGA) with a new structure was synthesized,and the pyridine group was successfully grafted onto the 3-oxadiglycolamide structure.Using MPyEDChDGA for efficient enrichment of rare earth ions,the self-assembled solids were recovered by simple filtration without further backextraction and final precipitation,achieving a one-step strategy for the recovery of rare earth ions.Several important parameters affecting the self-assembly extraction,including pH,diluent,temperature,and extractant concentration,were systematically evaluated using La(NO_(3))_(3),Tb(NO_(3))_(3),and Lu(NO_(3))_(3) as representatives.The self-assembled solids were investigated in detail by X-ray diffraction(XRD),scanning electron microscopy(SEM),1H nuclear magnetic resonance(1H NMR),Fourier transform infrared spectroscopy(FT-IR),Raman,and X-ray photoelectron spectroscopy(XPS) analyses.The stoichiometry of the extraction species was characterized using the Job's method and electrospray ionization mass spectrometry(ESI-MS).In addition,MPyEDChDGA was applied to the recovery of Sm in SmCoCu simulated liquid,and the results show that MPyEDChDGA has good selectivity of Sm from transition metals(Co,Cu).The separation factor of Sm/Co can reach 6281±117,which provides a new approach to recovering Sm from SmCoCu scrap magnets.This study presents an efficient and convenient new strategy for the recovery and separation of rare earth elements.展开更多
Recent advancements in computational and database technologies have led to the exponential growth of large-scale medical datasets,significantly increasing data complexity and dimensionality in medical diagnostics.Effi...Recent advancements in computational and database technologies have led to the exponential growth of large-scale medical datasets,significantly increasing data complexity and dimensionality in medical diagnostics.Efficient feature selection methods are critical for improving diagnostic accuracy,reducing computational costs,and enhancing the interpretability of predictive models.Particle Swarm Optimization(PSO),a widely used metaheuristic inspired by swarm intelligence,has shown considerable promise in feature selection tasks.However,conventional PSO often suffers from premature convergence and limited exploration capabilities,particularly in high-dimensional spaces.To overcome these limitations,this study proposes an enhanced PSO framework incorporating Orthogonal Initializa-tion and a Crossover Operator(OrPSOC).Orthogonal Initialization ensures a diverse and uniformly distributed initial particle population,substantially improving the algorithm’s exploration capability.The Crossover Operator,inspired by genetic algorithms,introduces additional diversity during the search process,effectively mitigating premature convergence and enhancing global search performance.The effectiveness of OrPSOC was rigorously evaluated on three benchmark medical datasets—Colon,Leukemia,and Prostate Tumor.Comparative analyses were conducted against traditional filter-based methods,including Fast Clustering-Based Feature Selection Technique(Fast-C),Minimum Redundancy Maximum Relevance(MinRedMaxRel),and Five-Way Joint Mutual Information(FJMI),as well as prominent metaheuristic algorithms such as standard PSO,Ant Colony Optimization(ACO),Comprehensive Learning Gravitational Search Algorithm(CLGSA),and Fuzzy-Based CLGSA(FCLGSA).Experimental results demonstrated that OrPSOC consistently outperformed these existing methods in terms of classification accuracy,computational efficiency,and result stability,achieving significant improvements even with fewer selected features.Additionally,a sensitivity analysis of the crossover parameter provided valuable insights into parameter tuning and its impact on model performance.These findings highlight the superiority and robustness of the proposed OrPSOC approach for feature selection in medical diagnostic applications and underscore its potential for broader adoption in various high-dimensional,data-driven fields.展开更多
Amphiphilic asymmetric brush copolymers(AABCs)possess unique self-assembly behaviors owing to their asymmetric brush architecture and multiple functionalities of multicomponent side chains.However,the synthesis of AAB...Amphiphilic asymmetric brush copolymers(AABCs)possess unique self-assembly behaviors owing to their asymmetric brush architecture and multiple functionalities of multicomponent side chains.However,the synthesis of AABCs presents challenges,which greatly limits the exploration of their self-assembly behaviors.In this work,we employed dissipative particle dynamics(DPD)simulations to investigate the self-assembly behaviors of AABCs in selective solution.By varying the copolymer concentration and structure,we conducted the self-assembly phase diagrams of AABCs,revealing complex morphologies such as channelized micelles with one or more solvophilic channels.Moreover,the number,surface area,and one-dimensional density distribution of the channelized micelles were calculated to demonstrate the internal structure and morphological transformation during the self-assembly process.Our findings indicate that the morphology of the internal solvophilic channels is greatly influenced by the copolymer structure,concentration,and interaction parameters between the different side chains.The simulation results are consistent with available experimental observations,which can offer theoretical insights into the self-assembly of AABCs.展开更多
The precise control over the hierarchical self-assembly of sophisticated structures with comparable complexities and functions relying on the modulation of basic building blocks is elusive and highly desirable.Here,we...The precise control over the hierarchical self-assembly of sophisticated structures with comparable complexities and functions relying on the modulation of basic building blocks is elusive and highly desirable.Here,we report a fluorinated N-heterocyclic carbene(NHC)–based pillarplex with a tunable quaternary structure,employed as an efficient building block for constructing hierarchical superstructures.Initially,multiple noncovalent interactions in the NHC-based pillarplex,particularly those between the fluorinated pillarplex and PF_(6)-anions,induce the formation of a supramolecular gel at high concentrations.Additionally,this hierarchical self-assembled structure can be regulated by adjusting anion types,facilitating the controlled transformation from a supramolecular gel into a supramolecular channel upon the introduction of four monocarboxylic acids as anions.The study provides insight into the construction and controlled regulation of superstructures based on NHC-based pillarplexes.展开更多
Polymerization-induced self-assembly(PISA)has become one of the most versatile approaches for scalable preparation of linear block copolymer nanoparticles with various morphologies.However,the controlled introduction ...Polymerization-induced self-assembly(PISA)has become one of the most versatile approaches for scalable preparation of linear block copolymer nanoparticles with various morphologies.However,the controlled introduction of branching into the core-forming block and the effect on the morphologies of block copolymer nanoparticles under PISA conditions have rarely been explored.Herein,a series of multifunctional macromolecular chain transfer agents(macro-CTAs)were first synthesized by a two-step green light-activated photoiniferter polymerization using two types of chain transfer monomers(CTMs).These macro-CTAs were then used to mediate reversible addition-fragmentation chain transfer(RAFT)dispersion polymerization of styrene(St)to prepare block copolymers with different core-forming block structures and the assemblies.The effect of the core-forming block structure on the morphology of block copolymer nanoparticles was investigated in detail.Transmission electron microscopy(TEM)analysis indicated that the brush-like core-forming block structure facilitated the formation of higher-order morphologies,while the branched core-forming block structure favored the formation of lower-order morphologies.Moreover,it was found that using macroCTAs with a shorter length also promoted the formation of higher-order morphologies.Finally,structures of block copolymers and the assemblies were further controlled by changing the structure of macro-CTA or using a binary mixture of two different macro-CTAs.We expect that this work not only sheds light on the synthesis of block copolymer nanoparticles but also provide important mechanistic insights into PISA of nonlinear block copolymers.展开更多
Mechanically interlocked molecules (MIMs) have unique properties with broad applications, yet constructing both knotted and linked topologies from the same ligand remains challenging due to their distinct geometric de...Mechanically interlocked molecules (MIMs) have unique properties with broad applications, yet constructing both knotted and linked topologies from the same ligand remains challenging due to their distinct geometric demands. To address this, we design and synthesize a conformationally adaptive ligand 4,7-bis(3-(pyridin-4-yl) phenyl) benzo[c][1,2,5]thiadiazole (L1) with a tunable torsional angle θ of N1C1C2N2 ranging from 7.5° to 108.9°. Utilizing coordination-driven self-assembly at ambient temperature, L1 selectively assembles with binuclear half-sandwich units RhB1, RhB2, RhB3, and RhB4 featuring Cp*^(Rh^(Ⅲ)) (Cp* = η^(5)-pentam-ethylcyclopentadienyl) into distinct topologies: Solomon links Rh-1, trefoil knots Rh-2, molecular tweezers Rh 3, and Rh-4, respectively. Crucially, the self-adaptability of ligand L1 directs topology formation through pro-gramming different combination of noncovalent interactions (π-x stacking, CH..π interaction, and lone pair-π interaction), thus navigating divergent assembly pathways by conformational switching, as evidenced by X-ray crystallography analysis, independent gradient model (IGM) analysis, detailed nuclear magnetic resonance (NMR) spectroscopy and electrospray ionization time-of-flight/mass spectrometry (ESI-TOF/MS). This strategy can also be extended to construct Cp*^(Irl^(Ⅲ)) analogs (Solomon links Ir-1, trefoil knots Ir-2, molecular tweezers Ir-3 and Ir-4), demonstrating metal-independent control and achieving intricate topologies in a high yield.展开更多
Antiferromagnetic(AFM)spintronics have sparked extensive research interest in the field of information storage due to the considerable advantages offered by antiferromagnets,including non-volatile data storage,higher ...Antiferromagnetic(AFM)spintronics have sparked extensive research interest in the field of information storage due to the considerable advantages offered by antiferromagnets,including non-volatile data storage,higher storage density,and accelerating data processing.However,the manipulation and detection of internal AFM order in antiferromagnets hinders their applications in spintronic devices.Here,we proposed a design idea for an AFM material that is self-assembled from one-dimensional(1D)ferromagnetic(FM)chains.To validate this idea,we screened a two-dimensional(2D)selfassembled CrBr_(2)antiferromagnet of an AFM semiconductor from a large amount of data.This 2D CrBr_(2)antiferromagnet is composed of 1D FM CrBr_(2)chains that are arranged in a staggered and parallel configuration.In this type of antiferromagnet,the write-data operation of information is achieved in 1D FM chains,followed by a self-assembly process driving the assembly of 1D FM chains into an antiferromagnet.These constituent 1D FM chains become decoupled by external perturbations,such as heat,pressure,strain,etc.,thereby realizing the read-data operation of information.We anticipate that this antiferromagnet,composed of 1D FM chains,can be realized not only in the 1D to 2D system,but also is expected to expand to 2D to three-dimensional(3D)system,and even 1D to 3D system.展开更多
基金the National Natural Science Foundation of China(No.U22A20437)Joint Fund of Science and Technology R&D Plan of Henan Province(No.222301420005)Program for Innovative Research Team(in Science and Technology)in University of Henan Province(No.24IRTSTHN001)for financial support.
文摘Large-area graphene films with defined uniformity,thickness and morphology are crucial for their applications in optoelectronic and photothermal devices.Herein,we demonstrate that oriented arrangement and ordered assembly of graphene oxide(GO)nanosheets in solution films can be realized to obtain the high-quality and large-area reduced GO(rGO)films.The key to the success of this process primarily lies in the control of GO solution shear force direction with array capillaries,achieving oriented arrangement of GO nanosheets in the solution film.Secondly,the control of GO nanosheet concentration and solution viscosity during solvent evaporation of solution film is key to achieve the ordered and disordered assembly of GO,featuring the smooth and wrinkled structure rGO films,respectively.Subsequently,the resultant smooth rGO film with ordered assembly exhibits excellent thermal conductivity and electronic conductivity(over 1800 S·cm-1).Meanwhile,the wrinkled rGO film with disordered assembly can be used as a coating layer on Al current collectors,demonstrating anticorrosion properties and enhanced material adhesive stability.As a result,with such collectors,the high-voltage Li//NCM811 batteries show a 6-fold increase in cycle stability,and the lithium-sulfur batteries with high sulfur loading show a 3-fold increase in cycle stability.
文摘Peroxymonosulfate(PMS)-assisted visible-light photocatalytic degradation of organic pollutants using graphitic carbon nitride(g-C_(3)N_(4))presents a promising and environmentally friendly approach.However,pristine g-C_(3)N_(4) suffers from limited visible-light absorption and low charge-carrier mobility.In this study,a phosphorus-doped tubular carbon nitride(5P-TCN)was synthesized via a precursor self-assembly method using phosphoric acid and melamine as raw materials,eliminating the need for organic solvents or templates.The 5P-TCN catalyst demonstrated enhanced visible-light absorption,improved charge transfer capability,and a 5.25-fold increase in specific surface area(31.092 m^(2)/g),which provided abundant active sites to efficiently drive the PMS-assisted photocatalytic reaction.The 5P-TCN/vis/PMS system exhibited exceptional degradation performance for organic pollutants across a broad pH range(3–9),achieving over 92%degradation of Rhodamine B(RhB)within 15 min.Notably,the system retained>98%RhB degradation efficiency after three consecutive operational cycles,demonstrating robust operational stability and reusability.Moreover,key parameters influencing,active radi-cals,degradation pathways,and potential mechanisms for RhB degradation were systematically investigated.This work proposes a green and cost-effective strategy for developing high-efficiency photocatalysts,while demon-strating the exceptional capability of a PMS-assisted photocatalytic system for rapid degradation of RhB.
基金supported by the National Research Foundation of Korea(NRF)grant funded by the Korean government(MSIT)(No.2020R1C1C1003375)。
文摘Recently,hollow carbon nanospheres(HCSs)have garnered significant attention as potential Li metal hosts owing to their unique large voids and ease of fabrication.However,similar to other nanoscale hosts,their practical performance is limited by inhomogeneous agglomeration,increased binder requirements,and high tortuosity within the electrode.To overcome these problems and high tortuosity within the electrode,this study introduces a pomegranate-like carbon microcluster composed of primary HCSs(P-CMs)as a novel Li metal host.This unique nanostructure can be easily prepared using the spray-drying technique,enabling its mass production.Comprehensive analyses with various tools demonstrate that compared with HCS hosts,the P-CM host requires a smaller amount of binder to fabricate a sufficiently robust and even surface electrode.Furthermore,owing to reduced tortuosity,the well-designed P-CM electrode can provide continuous and shortened pathways for electron/ion transport,accelerating the Li-ion transfer kinetics and prohibiting preferential Li plating at the upper region of the electrode.Due to these characteristics,Li metal can be effectively encapsulated in the large inner voids of the primary HCSs constituting the P-CM,thereby enhancing the electrochemical performance of P-CM hosts in Li metal batteries.Specifically,the Coulombic efficiency of the P-CM host can be maintained at 97%over 100 cycles,with a high Li deposition areal capacity of 3 mAh·cm^(-2)and long cycle life(1000 h,1 mA·cm^(-2),and 1.0 mAh·cm^(-2)).Furthermore,a full cell incorporating a LiFePO4 cathode exhibits excellent cycle life.
文摘Four glycoluril-based amphiphilic molecular clips(AMCs)M1~M4 have been prepared for intracellular delivery of short DNA.M1~M4 have two methyl groups on its convex surface and four cations on its aromatic side arm,which can be used to construct self-assembled nanoparticles in aqueous solution driven by hydrophobic interaction.Dynamic light scattering experiments show that M1 and M2 can be driven hydrophobically to aggregate into extremely stable nanoparticles in water at the micromolar concentrations.Fluorescence titration and zeta potential experiments support that the nanoparticles formed by M1 and M2 are able to efficiently encapsulate short DNA(sDNA).Fluorescence imaging and flow cytometry studies reveal that their nano sizes enable intracellular delivery of the encapsulated sDNA into both normal and cancer cells,with delivery percentage reaching up to 94%,while in vitro experiments indicate that the two compounds have excellent biocompatibility and low cytotoxicity.
基金supported by the National Key R&D Program(Grant No.2022YFA1404102)the National Natural Science Foundation of China(Grant Nos.U23A2073,12374250,and 12121004)+1 种基金Chinese Academy of Sciences(Grant No.YJKYYQ20170025)Hubei Province(Grant No.2021CFA027).
文摘We report on the measurement of shear viscosity in an ultracold Fermi gas with variable temperatures and tunable interactions.A quadrupole mode excitation in an isotropic harmonic trap is used to quantify the shear viscosity of the quantum gas within the hydrodynamic regime.The shear viscosity of the system as a function of temperature has been investigated,and the results closely align with calculations in the high-temperature limit utilizing a new definition of the cutoff radius.Through an adiabatic sweep across the Bardeen–Cooper–Schrieffer(BCS)to Bose–Einstein condensate(BEC)crossover,we find that the minimum value of the shear viscosity,as a function of interaction strength,is significantly shifted toward the BEC side.Furthermore,the behavior of the shear viscosity is asymmetric on both sides of the location of the minimum.
基金funded by the National Natural Science Foundation of China(U2102219 and 32370901)the Project of Zhongshan Biological Breeding Laboratory(ZSBBL-KY2023-06-3).
文摘A predictive model of meiotic crossover engineering would increase precision in crop breeding.We review the biological principles underlying crossover formation and chromosomal distribution,hierarchical control mechanisms enforcing crossover assurance,and an emerging phase-separation model determining crossover interference patterning.
基金funding support by the National Science Foundation(NSF)under grant numbers CBET-2110603the Air Force Office of Scientific Research(AFOSR)under contract number FA9550-12-1-0225supported by the State of North Carolina and the National Science Foundation(award number ECCS-2025064).
文摘Thermoelectric materials,capable of converting temperature gradients into electrical power,have been traditionally limited by a trade-off between thermopower and electrical conductivity.This study introduces a novel,broadly applicable approach that enhances both the spin-driven thermopower and the thermoelectric figure-of-merit(zT)without compromising electrical conductivity,using temperature-driven spin crossover.Our approach,supported by both theoretical and experimental evidence,is demonstrated through a case study of chromium doped-manganese telluride,but is not confined to this material and can be extended to other magnetic materials.By introducing dopants to create a high crystal field and exploiting the entropy changes associated with temperature-driven spin crossover,we achieved a significant increase in thermopower,by approximately 136μV K^(-1),representing more than a 200%enhancement at elevated temperatures within the paramagnetic domain.Our exploration of the bipolar semiconducting nature of these materials reveals that suppressing bipolar magnon/paramagnon-drag thermopower is key to understanding and utilizing spin crossover-driven thermopower.These findings,validated by inelastic neutron scattering,X-ray photoemission spectroscopy,thermal transport,and energy conversion measurements,shed light on crucial material design parameters.We provide a comprehensive framework that analyzes the interplay between spin entropy,hopping transport,and magnon/paramagnon lifetimes,paving the way for the development of high-performance spin-driven thermoelectric materials.
基金Project supported by the National Natural Science Foundation of China (Grant Nos. 52272268, 52250308, and 52102338)Beijing National Laboratory for Condensed Matter Physics (Grant No. 2024BNLCMPKF016)Fundamental Research Funding of Universities directly under the Chinese Central Government (Grant No. 2-9-2022-038)。
文摘The interplay between dimensionality and superconductivity is a central theme in understanding the behavior of low-dimensional superconductors. In this work, we investigate the dimensional crossover from quasi-two-dimensional(quasi-2D) to three-dimensional(3D) superconductivity in(Li,Fe)OHFeSe_(1-x)S_(x) single crystals driven by sulfur doping.Through detailed structural, electrical, and magnetic characterization, we identify a critical doping level(x = 0.53) where the system transitions from quasi-2D to 3D superconducting behavior. Reduced superconducting fluctuations and nonFermi liquid behavior near this critical point suggest the presence of competition between intralayer and interlayer pairing mechanisms. Fluctuation conductivity analysis reveals that the coherence length along the c-axis, ζ_(c)(0), and the interlayer coupling strength, Γ, increase significantly at x = 0.53, marking the onset of 3D superconductivity. These findings provide new insights into the role of dimensionality and interlayer coupling in modulating superconducting properties, positioning(Li,Fe)OHFeSe_(1-x)S_(x) as a unique platform for exploring crossover physics in iron-based superconductors.
基金supported by the National Natural Science Foundation of China(No.62075069 and 52303092)the Water Conservancy Technology project of Hunan Province,China(XSKJ2021000-32)+1 种基金the City University of Hong Kong(#7005507)the Open Project of Yunnan Precious Metals Laboratory Co.,Ltd(grant number YPML-2023050278).
文摘Nowadays,high-stable and ultrasensitive heavy metal detection is of utmost importance in water quality monitoring.Nanoparticle-enhanced laser-induced breakdown spectroscopy(NELIBS)shows high potential in hazardous metal detection,however,encounters unstable and weak signals due to nonuniform distribution of analytes.Herein,we developed an interface self-assembly(ISA)method to create a uniformly distributed gold nanolayer at a liquid-liquid interface for positive heavy metal ions capture and NELIBS analysis.The electrostatically selfassembled Au nanoparticles(NPs)-analytes membrane was prepared at the oil-water interface by injecting ethanol into the mixture of cyclohexane and Au NPs-analytes water solution.Then,the interface self-assembled Au NPs-analytes membrane was transformed onto a laser-processed superhydrophilic Si slide for detection.Three heavy metals(cadmium(Cd),barium(Ba),and chromium(Cr))were analyzed to evaluate the stability and sensitivity of the ISA method for NELIBS.The results(Cd:RSD=3.6%,LoD=0.654 mg/L;Ba:RSD=3.4%,LoD=0.236 mg/L;Cr:RSD=7.7%,LoD=1.367 mg/L)demonstrated signal enhancement and high-stable and ultrasensitive detection.The actual sample detection(Cd:RE=7.71%,Ba:RE=6.78%)illustrated great reliability.The ISA method,creating a uniform distribution of NP-analytes at the interface,has promising prospects in NELIBS.
基金financially supported by the National Natural Science Foundation of China(Nos.20904047 and 12074151)the Natural Science Foundation of Zhejiang Province(Nos.LY17A040001 and LY19F03004)。
文摘Diphenylalanine and its analogs cause many concerns owing to their perfect self-assembly properties in the fields of biology,medicine,and nanotechnology.Experimental research has shown that diphenylalanine-based analogs with ethylenediamine linkers(PA,P=phenylalanine,and A=analog)can self-assemble into spherical assemblies,which can serve as novel anticancer drug carriers.In this work,to understand the assembly pathways,drug loading behavior,and formation mechanism of PA aggregates at the molecular level,we carried out dissipative particle dynamics(DPD)simulations of PA molecule systems.Our simulation results demonstrate that PA molecules spontaneously assemble into nanospheres and can self-assemble into drug-loaded nanospheres upon addition of the cancer chemotherapeutic agent doxorubicin(DOX).We also found that the hydrophobic side chain beads of PA molecules exhibited a unique onion-like distribution inside the nanospheres,which was not observed in the experiment.The onion-like nanospheres were verified by calculating the radial distribution function(RDF)of the DPD beads.Furthermore,based on the analysis of the percentages of different interaction components in the total nonbonded energies,main chain-side chain interactions between PA molecules may be important in the formation of onion-like nanospheres,and the synergistic effects of main chain-side chain,main chain-drug,side chain-drug,and main chain-solvent interactions are significant in the formation of drug-loaded nanospheres.These findings provide new insights into the structure and self-assembly pathway of PA assemblies,which may be helpful for the design of efficient and effective drug delivery systems.
基金the support from Yunnan Fundamental Research Projects(202301BE070001-029,202401CF070129,202501CF070181)National Natural Science Foundation of China(22209012,22479067)Kunming University of Science and Technology Analysis and Testing Fund Support Project(2023T20220172)。
文摘In order to maximize the advantages of high energy density in Li metal batteries,it is necessary to match cathode materials with high specific capacities.Ni-rich layered oxides have been shown to reversibly embed more Li+during charge and discharge processes due to the increased Ni content in their crystal structure,thereby providing higher energy density.However,a significant challenge associated with Ni-rich layered oxide cathodes is the crossover effect,which arises from the dissolution of Ni^(2+)from the cathode,leading to a rapid decline in battery capacity.Through the delocalization-induced effect of solvent molecules,Ni^(2+)is transformed into a fluorinated transition metal inorganic phase layer,thereby forming a corrosion-resistant Li metal interface.This prevents solvent molecules from being reduced and degraded by Li metal anode.The surface of the Li metal anode exhibits a smooth and flat deposition morphology after long-term cycling.Furthermore,the introduction of Ni^(2+)can enhance the concentration gradient of transition metal ions near the cathode,thereby suppressing the dissolution process of transition metal ions.Even the NCM955 cathode with a mass load of 22 mg cm^(−2)also has great capacity retention after cycling.The Ni^(2+)induced by high electronegative functional groups of solvent under the electron delocalization effect,preventing the Ni ions dissolution of cathode and constructing a corrosion-resistant Li metal interface layer.This work provides new insights into suppressing crossover effects in Li metal batteries with high nickel cathodes.
基金supported by the National Natural Science Foundation of China(Nos.82061148012,82027806,21974019)SEU Innovation Capability Enhancement Plan for Doctoral Students(No.CXJH_SEU 24138)Postgraduate Research&Practice Innovation Program of Jiangsu Province(No.KYCX24_0469)。
文摘The potential of metal nanoclusters in biomedical applications is limited due to aggregation-caused quenching(ACQ).In this study,an in situ self-assembled pitaya structure was proposed to obtain stable fluorescence emission through protein coronas-controlled distance between gold nanoclusters(Au NCs).Interestingly,the gold ion complexes coated with proteins of low isoelectric point(pI)nucleate at the secondary structure of proteins with high p I through ionic exchange within cells,generating fluorescent Au NCs.It is worth noting that due to the steric hindrance formed by the protein coronas on the surface of Au NCs,the distance between Au NCs can be controlled,avoiding electron transfer caused by close proximity of Au NCs and inhibiting fluorescence ACQ.This strategy can achieve fluorescence imaging of clinical tissue samples without observable side effects.Therefore,this study proposes a distance-controllable self-assembled pitaya structure to provide a new approach for Au NCs with stable fluorescence.
文摘This study introduces a novel mathematical model to describe the progression of cholera by integrating fractional derivatives with both singular and non-singular kernels alongside stochastic differential equations over four distinct time intervals.The model incorporates three key fractional derivatives:the Caputo-Fabrizio fractional derivative with a non-singular kernel,the Caputo proportional constant fractional derivative with a singular kernel,and the Atangana-Baleanu fractional derivative with a non-singular kernel.We analyze the stability of the core model and apply various numerical methods to approximate the proposed crossover model.To achieve this,the approximation of Caputo proportional constant fractional derivative with Grünwald-Letnikov nonstandard finite difference method is used for the deterministic model with a singular kernel,while the Toufik-Atangana method is employed for models involving a non-singular Mittag-Leffler kernel.Additionally,the integral Caputo-Fabrizio approximation and a two-step Lagrange polynomial are utilized to approximate the model with a non-singular exponential decay kernel.For the stochastic component,the Milstein method is implemented to approximate the stochastic differential equations.The stability and effectiveness of the proposed model and methodologies are validated through numerical simulations and comparisons with real-world cholera data from Yemen.The results confirm the reliability and practical applicability of the model,providing strong theoretical and empirical support for the approach.
基金Project supported by the Natural Science Foundation of Shandong Province (ZR2022QB067)。
文摘The development of new and efficient extractants plays a key role in the separation and recovery of rare earth elements.In this pape r,the extractant(N,N-methyl py ridineethyl-N',N'-dicyclohexyl-3-oxadiglycolamide,MPyEDChDGA) with a new structure was synthesized,and the pyridine group was successfully grafted onto the 3-oxadiglycolamide structure.Using MPyEDChDGA for efficient enrichment of rare earth ions,the self-assembled solids were recovered by simple filtration without further backextraction and final precipitation,achieving a one-step strategy for the recovery of rare earth ions.Several important parameters affecting the self-assembly extraction,including pH,diluent,temperature,and extractant concentration,were systematically evaluated using La(NO_(3))_(3),Tb(NO_(3))_(3),and Lu(NO_(3))_(3) as representatives.The self-assembled solids were investigated in detail by X-ray diffraction(XRD),scanning electron microscopy(SEM),1H nuclear magnetic resonance(1H NMR),Fourier transform infrared spectroscopy(FT-IR),Raman,and X-ray photoelectron spectroscopy(XPS) analyses.The stoichiometry of the extraction species was characterized using the Job's method and electrospray ionization mass spectrometry(ESI-MS).In addition,MPyEDChDGA was applied to the recovery of Sm in SmCoCu simulated liquid,and the results show that MPyEDChDGA has good selectivity of Sm from transition metals(Co,Cu).The separation factor of Sm/Co can reach 6281±117,which provides a new approach to recovering Sm from SmCoCu scrap magnets.This study presents an efficient and convenient new strategy for the recovery and separation of rare earth elements.
文摘Recent advancements in computational and database technologies have led to the exponential growth of large-scale medical datasets,significantly increasing data complexity and dimensionality in medical diagnostics.Efficient feature selection methods are critical for improving diagnostic accuracy,reducing computational costs,and enhancing the interpretability of predictive models.Particle Swarm Optimization(PSO),a widely used metaheuristic inspired by swarm intelligence,has shown considerable promise in feature selection tasks.However,conventional PSO often suffers from premature convergence and limited exploration capabilities,particularly in high-dimensional spaces.To overcome these limitations,this study proposes an enhanced PSO framework incorporating Orthogonal Initializa-tion and a Crossover Operator(OrPSOC).Orthogonal Initialization ensures a diverse and uniformly distributed initial particle population,substantially improving the algorithm’s exploration capability.The Crossover Operator,inspired by genetic algorithms,introduces additional diversity during the search process,effectively mitigating premature convergence and enhancing global search performance.The effectiveness of OrPSOC was rigorously evaluated on three benchmark medical datasets—Colon,Leukemia,and Prostate Tumor.Comparative analyses were conducted against traditional filter-based methods,including Fast Clustering-Based Feature Selection Technique(Fast-C),Minimum Redundancy Maximum Relevance(MinRedMaxRel),and Five-Way Joint Mutual Information(FJMI),as well as prominent metaheuristic algorithms such as standard PSO,Ant Colony Optimization(ACO),Comprehensive Learning Gravitational Search Algorithm(CLGSA),and Fuzzy-Based CLGSA(FCLGSA).Experimental results demonstrated that OrPSOC consistently outperformed these existing methods in terms of classification accuracy,computational efficiency,and result stability,achieving significant improvements even with fewer selected features.Additionally,a sensitivity analysis of the crossover parameter provided valuable insights into parameter tuning and its impact on model performance.These findings highlight the superiority and robustness of the proposed OrPSOC approach for feature selection in medical diagnostic applications and underscore its potential for broader adoption in various high-dimensional,data-driven fields.
基金supported by the National Science Foundation for Distinguished Young Scholars(No.52325308)the National Natural Science Foundation of China(Nos.52273008 and 52073092)+1 种基金Shanghai Scientific and Technological Innovation Projects(No.22ZR1479300)Shanghai Rising-Star Program(No.23QA1402500).
文摘Amphiphilic asymmetric brush copolymers(AABCs)possess unique self-assembly behaviors owing to their asymmetric brush architecture and multiple functionalities of multicomponent side chains.However,the synthesis of AABCs presents challenges,which greatly limits the exploration of their self-assembly behaviors.In this work,we employed dissipative particle dynamics(DPD)simulations to investigate the self-assembly behaviors of AABCs in selective solution.By varying the copolymer concentration and structure,we conducted the self-assembly phase diagrams of AABCs,revealing complex morphologies such as channelized micelles with one or more solvophilic channels.Moreover,the number,surface area,and one-dimensional density distribution of the channelized micelles were calculated to demonstrate the internal structure and morphological transformation during the self-assembly process.Our findings indicate that the morphology of the internal solvophilic channels is greatly influenced by the copolymer structure,concentration,and interaction parameters between the different side chains.The simulation results are consistent with available experimental observations,which can offer theoretical insights into the self-assembly of AABCs.
基金financial support from the National Natural Science Fund for Distinguished Young Scholars of China(No.22025107)Shaanxi Fundamental Science Research Project for Chemistry&Biology(No.22JHZ003)+2 种基金the Key International Scientific and Technological Cooperation and Exchange Project of Shaanxi Province(No.2023-GHZD-15)the National Youth Top-notch Talent Support Program of Chinathe FM&EM International Joint Laboratory of Northwest University。
文摘The precise control over the hierarchical self-assembly of sophisticated structures with comparable complexities and functions relying on the modulation of basic building blocks is elusive and highly desirable.Here,we report a fluorinated N-heterocyclic carbene(NHC)–based pillarplex with a tunable quaternary structure,employed as an efficient building block for constructing hierarchical superstructures.Initially,multiple noncovalent interactions in the NHC-based pillarplex,particularly those between the fluorinated pillarplex and PF_(6)-anions,induce the formation of a supramolecular gel at high concentrations.Additionally,this hierarchical self-assembled structure can be regulated by adjusting anion types,facilitating the controlled transformation from a supramolecular gel into a supramolecular channel upon the introduction of four monocarboxylic acids as anions.The study provides insight into the construction and controlled regulation of superstructures based on NHC-based pillarplexes.
基金financially supported by the National Natural Science Foundation of China(Nos.22171055 and 52222301)the Guangdong Natural Science Foundation for Distinguished Young Scholar(No.2022B1515020078)the Science and Technology Program of Guangzhou(No.2024A04J2821)。
文摘Polymerization-induced self-assembly(PISA)has become one of the most versatile approaches for scalable preparation of linear block copolymer nanoparticles with various morphologies.However,the controlled introduction of branching into the core-forming block and the effect on the morphologies of block copolymer nanoparticles under PISA conditions have rarely been explored.Herein,a series of multifunctional macromolecular chain transfer agents(macro-CTAs)were first synthesized by a two-step green light-activated photoiniferter polymerization using two types of chain transfer monomers(CTMs).These macro-CTAs were then used to mediate reversible addition-fragmentation chain transfer(RAFT)dispersion polymerization of styrene(St)to prepare block copolymers with different core-forming block structures and the assemblies.The effect of the core-forming block structure on the morphology of block copolymer nanoparticles was investigated in detail.Transmission electron microscopy(TEM)analysis indicated that the brush-like core-forming block structure facilitated the formation of higher-order morphologies,while the branched core-forming block structure favored the formation of lower-order morphologies.Moreover,it was found that using macroCTAs with a shorter length also promoted the formation of higher-order morphologies.Finally,structures of block copolymers and the assemblies were further controlled by changing the structure of macro-CTA or using a binary mixture of two different macro-CTAs.We expect that this work not only sheds light on the synthesis of block copolymer nanoparticles but also provide important mechanistic insights into PISA of nonlinear block copolymers.
基金Department of Chemistry,Fudan Uni-versity,the National Natural Science Foundation of China(22031003,21720102004)the Shanghai Science Technology Committee(19DZ227010O)the Alexander von Humboldt Foundation for a Humboldt Research Award.
文摘Mechanically interlocked molecules (MIMs) have unique properties with broad applications, yet constructing both knotted and linked topologies from the same ligand remains challenging due to their distinct geometric demands. To address this, we design and synthesize a conformationally adaptive ligand 4,7-bis(3-(pyridin-4-yl) phenyl) benzo[c][1,2,5]thiadiazole (L1) with a tunable torsional angle θ of N1C1C2N2 ranging from 7.5° to 108.9°. Utilizing coordination-driven self-assembly at ambient temperature, L1 selectively assembles with binuclear half-sandwich units RhB1, RhB2, RhB3, and RhB4 featuring Cp*^(Rh^(Ⅲ)) (Cp* = η^(5)-pentam-ethylcyclopentadienyl) into distinct topologies: Solomon links Rh-1, trefoil knots Rh-2, molecular tweezers Rh 3, and Rh-4, respectively. Crucially, the self-adaptability of ligand L1 directs topology formation through pro-gramming different combination of noncovalent interactions (π-x stacking, CH..π interaction, and lone pair-π interaction), thus navigating divergent assembly pathways by conformational switching, as evidenced by X-ray crystallography analysis, independent gradient model (IGM) analysis, detailed nuclear magnetic resonance (NMR) spectroscopy and electrospray ionization time-of-flight/mass spectrometry (ESI-TOF/MS). This strategy can also be extended to construct Cp*^(Irl^(Ⅲ)) analogs (Solomon links Ir-1, trefoil knots Ir-2, molecular tweezers Ir-3 and Ir-4), demonstrating metal-independent control and achieving intricate topologies in a high yield.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.12435001,12304006,and 12404265)the Natural Science Foundation of Shanghai,China(Grant No.23JC1401400)+1 种基金the Fundamental Research Funds for the Central Universities of East China University,the Natural Science Foundation of WIUCAS(Grant No.WIUCASQD2023004)the Natural Science Foundation of Wenzhou(Grant No.L2023005)。
文摘Antiferromagnetic(AFM)spintronics have sparked extensive research interest in the field of information storage due to the considerable advantages offered by antiferromagnets,including non-volatile data storage,higher storage density,and accelerating data processing.However,the manipulation and detection of internal AFM order in antiferromagnets hinders their applications in spintronic devices.Here,we proposed a design idea for an AFM material that is self-assembled from one-dimensional(1D)ferromagnetic(FM)chains.To validate this idea,we screened a two-dimensional(2D)selfassembled CrBr_(2)antiferromagnet of an AFM semiconductor from a large amount of data.This 2D CrBr_(2)antiferromagnet is composed of 1D FM CrBr_(2)chains that are arranged in a staggered and parallel configuration.In this type of antiferromagnet,the write-data operation of information is achieved in 1D FM chains,followed by a self-assembly process driving the assembly of 1D FM chains into an antiferromagnet.These constituent 1D FM chains become decoupled by external perturbations,such as heat,pressure,strain,etc.,thereby realizing the read-data operation of information.We anticipate that this antiferromagnet,composed of 1D FM chains,can be realized not only in the 1D to 2D system,but also is expected to expand to 2D to three-dimensional(3D)system,and even 1D to 3D system.