The linker defect engineering for MOFs is a viable strategy that usually can effectively augment conductivity to further promote charge carrier separation,which is the most excellent conductivity of preserved metal cl...The linker defect engineering for MOFs is a viable strategy that usually can effectively augment conductivity to further promote charge carrier separation,which is the most excellent conductivity of preserved metal clusters.However,the partially missing photosensitive linker often leads to the diminished light utilization efficiency.As we know,in the linker defect engineering,addressing the lack of photosensitivity while maintaining outstanding conductivity is still in its infancy.In this essay,the linkerdefective NH_(2)-MIL-125 was obtained by adding the glacial acetic acid regulator,subsequently,the excellent light-responsive Pt/CQDs with up-conversion effect was in-situ encapsulated into the enlarged pore space of linker-defective NH_(2)-MIL-125.It is excited that the fabricated dual-functional composite ideally integrates photosensitivity and conductivity for photocatalytic hydrogen evolution and NO elimination.The optimal Pt/CQDs@NM-125-4 exhibited very superior photocatalytic hydrogen evolution(28.75mmol/g),it was 11.63 times as that of the initial NH_(2)-MIL-125(2.47 mmol/g)and 1.4 times as that of the defective NM-125-4(20.46 mmol/g).In addition,the excellent photocatalytic NO removal efficiency was 52.12%for Pt/CQDs@NM-125-4,whereas the original NH_(2)-MIL-125 only reached 30%and the defective NM-125-4 achieved 44.96%.The corresponding optical and electrical characterization based on UV-vis,up-conversion photoluminescence(UCPL),and electrochemical impedance spectroscopy(EIS)etc.demonstrated the defect engineering accelerates the charge carriers transfer via enhancing conductivity,and the in-situ confined up-conversion Pt/CQDs promote the visible light response.Our work presents a feasible avenue to integrate photosensitivity and conductivity via in-situ fabricating excellent lightresponsive Pt/CQDs within linker-defective NH_(2)-MIL-125 for further significantly boosting photocatalytic performance.展开更多
To develop new up-conversion luminescent materials for non-contact optical thermometer with high sensitivity and temperature re solution,a battery of KBaGd(MoO_(4))_(3):Yb^(3+),Ho^(3+)phosphors were fabricated through...To develop new up-conversion luminescent materials for non-contact optical thermometer with high sensitivity and temperature re solution,a battery of KBaGd(MoO_(4))_(3):Yb^(3+),Ho^(3+)phosphors were fabricated through solid reaction process.The crystal structure,up-conversion luminescence,energy transfer,thermal stability and optical temperature sensing performances were studied in detail.Under 980 nm laser excitation,the KBaGd(MoO_(4))_(3):Yb^(3+),Ho^(3+)phosphor exhibits distinctive emission bands of Ho^(3+)at545,660,and 755 nm,and excellent illuminant performance.Based on the thermally coupled levels(TCLs)of Ho^(3+),both the relative sensitivity(S_(r))and absolute sensitivity(S_(a))display similar change trends,with the highest values of 6.73%/K(@298 K)and 5.69%/K(@298 K),respectively.Furthermore,the highest Saof 13.90%/K(@623 K)and the ultimate Srof 0.62%/K(@298 K)are achieved based on non-TCLs of Ho^(3+).Therefore,KBaGd(MoO_(4))_(3):Yb^(3+),Ho^(3+)phosphor is a promising candidate for self-referenced optical thermometry.展开更多
For developing and utilizing near-infrared(NIR)energy in sunlight,NaYF4:Yb,Tm(NYFYT)up-conversion Iuminescent powder was combined with Ag_(3)PO_(4)(AP)and Ag_(3)PO_(4)/Pt nanoparticles(AP/PtNPs)as a photocatalyst.Driv...For developing and utilizing near-infrared(NIR)energy in sunlight,NaYF4:Yb,Tm(NYFYT)up-conversion Iuminescent powder was combined with Ag_(3)PO_(4)(AP)and Ag_(3)PO_(4)/Pt nanoparticles(AP/PtNPs)as a photocatalyst.Driven by NIR light,NYFYT produces up-conversion emission at 348,364,453 and 478 nm,effectively stimulating the photocatalytic degradation performance of AP and AP/PtNPs,Under xenon lamp irradiation,the apparent rate constants(k)for Ag_(3)PO_(4)/Pt nanoparticles-NaYF4:Yb,Tm(AP/PtNPs-NYFYT)in photocatalytic degradation of rhodamine B(Rh B)and phenol are 5.51 and 12.82 times higher than those of AP and 1.90 and 2.37 times higher than those of AP-NYFYT-50 wt%,respectively.In addition,under 980nm laser irradiation,rate constants are 3.26 and 4.16 times higher than those of AP-NYFYT-50 wt%,respectively.These results indicate that the combination of NYFYT and AP expands the absorption range of the composite photocatalyst and facilitates the NIR-driven photocatalytic process.The introduction of PtNPs effectively prevents the electron-hole recombination and the reduction of Ag+,accelerating the redox reaction and promoting the photocatalytic activity and stability of AP.展开更多
Up-conversion(UC)luminescent materials doped with Ln^(3+)ions possess excellent optical properties and extensive applications in the formulation of multifunctional fluorescence ink.Printing technology offers various m...Up-conversion(UC)luminescent materials doped with Ln^(3+)ions possess excellent optical properties and extensive applications in the formulation of multifunctional fluorescence ink.Printing technology offers various methods for the preparation of UC fluorescent inks.This study introduced the optical properties of luminescent materials doped with Ln^(3+)ions,including luminescence characteristics and spectral characteristics,which provide a basis for the subsequent printing process.We also reviewed different printing techniques,including direct writing,screen printing,laser printing,inkjet printing,and aerosol jet printing(AJP),developed so far in the literature and explored the printing process of ink characteristics.However,the printing process of inks was explored and their potential for various applications was maximized.Therefore,the printing technology of UC fluorescent inks still faces challenges in different aspects.This review also points out the direction for future in-depth research,which is expected to promote further development and innovation in the field.展开更多
Diesel accounts for over 60%of the products derived from direct coal liquefaction(DCL).Compared to petroleum-based diesel,DCL diesel exhibits a cetane number ranging from 30 to 40,which fails to meet the automotive di...Diesel accounts for over 60%of the products derived from direct coal liquefaction(DCL).Compared to petroleum-based diesel,DCL diesel exhibits a cetane number ranging from 30 to 40,which fails to meet the automotive diesel standard requirement of≥45.Therefore,rapid and accurate analysis of its chemical composition is crucial for property optimization to meet fuel specifications by component blending.Thought traditional methods like gas chromatography offer high accuracy,they are unsuitable for rapid online analysis under industrial conditions.Near-infrared(NIR)spectroscopy can provide advantages in rapid,non-destructive analysis.Its application however,is limited by the complexity of spectral data interpretation.Machine learning(ML)is effective method for extracting valuable information from spectra and establishing high-precision prediction models.This study integrates NIR spectroscopy with ML to construct a spectral-composition database for DCL diesel.Feature extraction was performed using the correlation coefficient and mutual information methods to screen key wavelength variables and reduce data dimensionality.Subsequently,the predictive performance of three ML models—Lasso,SVR and XGBoost—was compared.Results indicate that excluding spectral data with absorbance greater than 1 significantly enhances model accuracy,increasing the test set R^(2) from 0.85 to 0.96.After feature extraction,the optimal number of wavelength variables was reduced to 177,substantially improving computational efficiency.Among the models evaluated,the SVR-MI-0.9 model,based on mutual information feature selection,demonstrated the best performance,achieving training and test set R^(2) values both exceeding 0.98.This model enables precise prediction of paraffin,naphthene,and aromatic hydrocarbon contents.This research provides a robust methodology for intelligent online quality monitoring.An intelligent NIR spectroscopy data analysis software was independently developed based on the established model.Compared with comprehensive two-dimensional gas chromatography,the software reduced the analysis time by over 98%,with an absolute prediction error below 0.2%.Thus,rapid analysis of DCL diesel components was successfully realized.展开更多
The efficiency and stability of catalysts for photocatalytic hydrogen evolution(PHE)are largely governed by the charge transfer behaviors across the heterojunction interfaces.In this study,CuO,a typical semiconductor ...The efficiency and stability of catalysts for photocatalytic hydrogen evolution(PHE)are largely governed by the charge transfer behaviors across the heterojunction interfaces.In this study,CuO,a typical semiconductor featuring a broad spectral absorption range,is successfully employed as the electron acceptor to combine with CdS for constructing a S-scheme heterojunction.The optimized photocatalyst(CdSCuO2∶1)delivers an exceptional hydrogen evolution rate of 18.89 mmol/(g·h),4.15-fold higher compared with bare CdS.X-ray photoelectron spectroscopy(XPS)and ultraviolet-visible diffuse reflection absorption spectroscopy(UV-vis DRS)confirmed the S-scheme band structure of the composites.Moreover,the surface photovoltage(SPV)and electron paramagnetic resonance(EPR)indicated that the photogenerated electrons and photogenerated holes of CdS-CuO2∶1 were respectively transferred to the conduction band(CB)of CdS with a higher reduction potential and the valence band(VB)of CuO with a higher oxidation potential under illumination,as expected for the S-scheme mechanism.Density-functional-theory calculations of the electron density difference(EDD)disclose an interfacial electric field oriented from CdS to CuO.This built-in field suppresses charge recombination and accelerates carrier migration,rationalizing the markedly enhanced PHE activity.This study offers a novel strategy for designing S-scheme heterojunctions with high light harvesting and charge utilization toward sustainable solar-tohydrogen conversion.展开更多
The fatigue crack growth rate of a novel Ti-6Al-4V-1Mo titanium alloy,which is developed for laser directed energy deposition technique,was investigated before and after cyclic heat treatment(CHT).Changes in microstru...The fatigue crack growth rate of a novel Ti-6Al-4V-1Mo titanium alloy,which is developed for laser directed energy deposition technique,was investigated before and after cyclic heat treatment(CHT).Changes in microstructure,fracture surfaces,and crack growth paths were analyzed before and after CHT.Results indicate that in the stable crack growth region,the growth rates for the as-deposited and cyclic heat-treated specimens follow the relationships da/dN=1.8651×10^(−8)(ΔK)^(3.2271)and da/dN=1.4112×10^(−8)(ΔK)^(3.1125),respectively.Compared with that at the as-deposited state,the microstructure after CHT is transformed from a uniform basket-weave microstructure to a dual-phase microstructure consisting of near-sphericalαandβ-transformed matrix phases.The cyclic process also disrupts the continuity of the grain boundaryα(αGB)at the primaryβ-phase grain boundary.The coarsening of primaryαand the disruption ofαGB continuity are the primary factors to release stress concentration and promote crack deflection,thereby decreasing the fatigue crack growth rate.Additionally,the increased occurrence of crack branching,secondary cracking,and crack bridging in cyclic heat-treated specimens further reduces the crack driving force and slows the fatigue crack growth rate.展开更多
Directional three-dimensional carbon-based foams are emerging as highly attractive candidates for promising electromagnetic wave absorbing materials(EWAMs)thanks to their unique architecture,but their construction usu...Directional three-dimensional carbon-based foams are emerging as highly attractive candidates for promising electromagnetic wave absorbing materials(EWAMs)thanks to their unique architecture,but their construction usually involves complex procedures and extremely depends on unidirectional freezing technique.Herein,we propose a groundbreaking approach that leverages the assemblies of salting-out protein induced by ammonium metatungstate(AM)as the precursor,and then acquire directional three-dimensional carbon-based foams through simple pyrolysis.The electrostatic interaction between AM and protein ensures well dispersion of WC_(1−x)nanoparticles on carbon frameworks.The content of WC_(1−x)nanoparticles can be rationally regulated by AM dosage,and it also affects the electromagnetic(EM)properties of final carbon-based foams.The optimized foam exhibits exceptional EM absorption performance,achieving a remarkable minimum reflection loss of−72.0 dB and an effective absorption bandwidth of 6.3 GHz when EM wave propagates parallel to the directional pores.Such performance benefits from the synergistic effects of macroporous architecture and compositional design.Although there is a directional dependence of EM absorption,radar stealth simulation demonstrates that these foams can still promise considerable reduction in radar cross section with the change of incident angle.Moreover,COMSOL simulation further identifies their good performance in preventing EM interference among different electronic components.展开更多
The Cooling-Storage-Ring External-target Experiment(CEE)at the Heavy Ion Research Facility in Lanzhou(HIRFL)is designed to study the properties of nuclear matter created in heavy-ion collisions at beam energies from a...The Cooling-Storage-Ring External-target Experiment(CEE)at the Heavy Ion Research Facility in Lanzhou(HIRFL)is designed to study the properties of nuclear matter created in heavy-ion collisions at beam energies from a few hundred MeV/u up to 1 GeV/u.It aims to facilitate research on the quantum chromodynamics(QCD)phase structure in the high-baryondensity region.Collective flow is a fundamental observable in heavy-ion collision experiments,providing information on the bulk properties of the produced matter.Although the standard event plane method has been widely used to measure collective flow,it is still important to validate and optimize this method for the CEE spectrometer.In this paper,we study the experimental procedures for measuring directed flow in^(238)U+^(238)U collisions at 500 MeV/u,using event planes reconstructed by Multi-Wire Drift Chamber and Zero Degree Calorimeter,respectively.Jet AA Microscopic(JAM)transport generator is used to generate events,and the detector response is simulated by the CEE Fast Simulation(CFS)package.Finally,the optimal kinematic region for proton directed flow measurements is discussed for the future CEE experiment.展开更多
For a multi-frequency non-reciprocal optical device,we first realize multi-frequency optical non-reciprocal transmission using a non-Hermitian multi-mode resonator array.Practically,multi-frequency operation can add c...For a multi-frequency non-reciprocal optical device,we first realize multi-frequency optical non-reciprocal transmission using a non-Hermitian multi-mode resonator array.Practically,multi-frequency operation can add channels to the non-reciprocal optical device and the non-reciprocity can route optical signals and prevent the reverse flow of noise.Using the Scully–Lamb model and gain saturation effect,we accomplish dual-frequency non-reciprocal transmission by introducing nonlinearity into a linear array of four-mode resonators.The accomplishment is directly demonstrated by the non-reciprocal transmission phenomena present in the non-divergent peaks.For example,a directional cyclic amplifier is constructed with non-reciprocal units.Regarding potential applications,non-reciprocal optical systems can be employed in dual-frequency control,parallel information processing,photonic integrated circuits,optical devices and so on.展开更多
Objective:To explore the interventional room nursing and its application effects in patients with ischemic stroke treated with tirofiban combined with direct thrombectomy.Methods:A total of 61 patients with ischemic s...Objective:To explore the interventional room nursing and its application effects in patients with ischemic stroke treated with tirofiban combined with direct thrombectomy.Methods:A total of 61 patients with ischemic stroke admitted to our hospital from June 2024 to June 2025 were selected and divided into two groups using the red and blue ball method:the control group(n=30,receiving routine interventional room nursing)and the observation group(n=31,receiving additional tirofiban medication-specific nursing+individualized interventional nursing on the basis of routine nursing).The cerebral hemodynamic indicators,adverse reactions,effectiveness of complication nursing,and nursing satisfaction were compared between the two groups.Results:After 7 days of treatment,the observation group had lower cerebrovascular peripheral resistance and higher mean blood flow velocity and mean blood flow volume compared to the control group(all p<0.05).The observation group had a higher effectiveness rate of complication nursing than the control group,with a statistically significant difference(p<0.05).The nursing satisfaction in the observation group(96.77%)was higher than that in the control group(80.00%),with a statistically significant difference(χ^(2)=4.223,p=0.040<0.05).Conclusion:Tirofiban combined with direct thrombectomy can significantly improve cerebral hemodynamics,enhance the effectiveness of complication nursing,and increase patient satisfaction in patients with ischemic stroke.展开更多
BACKGROUND Drug utilization research has an important role in assisting the healthcare administration to know,compute,and refine the prescription whose principal objective is to enable the rational use of drugs.Resear...BACKGROUND Drug utilization research has an important role in assisting the healthcare administration to know,compute,and refine the prescription whose principal objective is to enable the rational use of drugs.Research in developing nations relating to the cost of treatment is scarce when compared with developed countries.Thus,the drug utilization research studies from developing nations are most needed,and their number has been growing.AIM To evaluate patterns of utilization of antipsychotic drugs and direct medical cost analysis in patients newly diagnosed with schizophrenia.METHODS The present study was observational in type and based on a retrospective cohort to evaluate patterns of utilization of antipsychotic drugs using World Health Organization(WHO)core prescribing indicators and anatomical therapeutic chemical/defined daily dose indicators.We also calculated direct medical costs for a period of 6 months.RESULTS This study has found that atypical antipsychotics are the mainstay of treatment for schizophrenia in every age group and subcategories of schizophrenia.The evaluation based on WHO prescribing indicators showed a low average number of drugs per prescription and low prescribing frequency of antipsychotics from the National List of Essential Medicines 2015 and the WHO Essential Medicines List 2019.The total mean drug cost of our study was 1396 Indian rupees.The total mean cost due to the investigation in our study was 1017.34 Indian rupees.Therefore,the total mean direct medical cost incurred on patients in our study was 4337.28 Indian rupees.CONCLUSION The information from the present study can be used for reviewing and updating treatment policy at the institutional level.展开更多
Efficient energy utilization in covert communication sustains covertness while assuring communication quality and efficiency.This paper investigates covert communication energy efficiency(EE)in direct uplink satellite...Efficient energy utilization in covert communication sustains covertness while assuring communication quality and efficiency.This paper investigates covert communication energy efficiency(EE)in direct uplink satellite-ground communications,focusing on enhancing system EE via optimized transmit beamforming and satellite orbit altitude selection.This paper first establishes an optimization problem to maximize system EE in a direct uplink satelliteground covert communication scenario.To solve this non-convex optimization problem,it is decomposed into two subproblems and solved using the successive convex approximation(SCA)method.Based on the above methods,this paper proposes an overall iterative optimization algorithm.Simulation results demonstrate that the proposed algorithm surpasses the conventional baseline algorithms in terms of system EE.Furthermore,they elucidate the correlation between the amount of information received by the receiver and the variations in the satellite’s orbital altitude.展开更多
This paper is dedicated to fixed-time passivity and synchronization for multi-weighted spatiotemporal directed networks.First,to achieve fixed-time passivity,a type of decentralized power-law controller is developed,i...This paper is dedicated to fixed-time passivity and synchronization for multi-weighted spatiotemporal directed networks.First,to achieve fixed-time passivity,a type of decentralized power-law controller is developed,in which only one parameter needs to be adjusted in the power-law terms;this greatly decreases the inconvenience of parameter adjustment.Second,several fixed-time passivity criteria with LMI forms are derived by using a Gauss divergence theorem to deal with the spatial diffusion of nodes and by applying the Hölder’s inequality to dispose rigorously the power-law term greater than one in the designed control scheme;this improves the previous theoretical analysis.Additionally,the fixed-time synchronization of spatiotemporal directed networks with multi-weights is addressed as a direct result of fixed-time strict passivity.Finally,a numerical example is presented in order to show the validity of the theoretical analysis.展开更多
Biopolymeric nanocomposites have attracted considerable attention because of their biocompatibility,biodegradability,and unique physicochemical properties.It is essential to manufacture three-dimensional(3D)biocompati...Biopolymeric nanocomposites have attracted considerable attention because of their biocompatibility,biodegradability,and unique physicochemical properties.It is essential to manufacture three-dimensional(3D)biocompatible micro/nanostructures using biopolymeric nanocomposites.Herein,we demonstrate the high-fidelity fabrication of biocompatible 3D features with sub-50 nm resolution using femtosecond laser direct writing(FsLDW)of a biopolymeric nanocomposite composed of egg white and sulfonated graphene(S-graphene).The biopolymer nanocomposite acts as a negative photoresist suitable for water-based lithography.The introduction of S-graphene not only dramatically lowered the laser power threshold but also significantly modulated the morphology of the 3D features constructed by FsLDW.Microstructures with porous,rough,or smooth morphologies were obtained by optimizing the S-graphene concentration and laser scanning speed.The fabricated egg-white/S-graphene microstructures exhibited biocompatibility and environmental degradability.Egg white/S-graphene was also employed to fabricate diffractive gratings with superior optical quality.This study provides a promising method to manufacture biocompatible 3D features with controllable morphology,which has potential applications in biological and photonic fields.展开更多
This article studies the consensus problem with directed graphs for general linear multi-agent systems.New distributed state-feedback protocols with dynamic event-triggered(DET)mechanisms are proposed for directed gra...This article studies the consensus problem with directed graphs for general linear multi-agent systems.New distributed state-feedback protocols with dynamic event-triggered(DET)mechanisms are proposed for directed graphs that are strongly connected and weight-balanced,general strongly connected,and have spanning trees,respectively.It is proven that strictly positive minimum inter-event times(MIETs)are ensured using the designed DET mechanisms.Several numerical examples are presented to illustrate the effectiveness of the theoretical results.Compared with existing results,our results have the following merits:1)DET mechanisms are designed to determine the sampling instants,which can reduce the communication frequency between agents compared with static mechanisms;2)We focus on the consensus problem on directed graphs,which is more general than existing related results on undirected graphs;3)The existence of positive MIETs is shown to be guaranteed by the designed DET sampling strategies while existing related results can only exclude Zeno behavior.展开更多
We report for the first time the combination of directed evolution focused on enhancing and reversing the stereoselectivity of an enzyme with Cu(I)-mediated click chemistry(CuAAC),providing an asymmetric click approac...We report for the first time the combination of directed evolution focused on enhancing and reversing the stereoselectivity of an enzyme with Cu(I)-mediated click chemistry(CuAAC),providing an asymmetric click approach for versatile chiral triazoles products.In this study,the halohydrin dehalogenase HheG was used as the enzyme which was evolved to induce a stereoselective ring-opening reaction of cyclic epoxides in the presence of NaN3 with the formation of chiral azido products.Two mutants of opposite stereopreference were generated,which convert cyclohexene oxide as well as cycloheptene oxide to(1S,2S)-2-azidocyclohexanol,(1R,2R)-2-azidocyclohexanol,(1S,2S)-2-azidocycloheptanol and(1R,2R)-2-azidocycloheptanol with essentially high stereoselectivity.The chiral products were then subjected to CuAAC in reactions with structurally different alkynes.Since HheG was found to be compatible with Cu(I),the process was also performed successfully in a unique 2-step one-pot process leading to various chiral triazoles.In order to understand the enhancement and reversal of the evolved enantioselectivity,QM and MD computations were performed.This approach harnesses the modifiability and high stereoselectivity of the evolved biocatalysts in combination with click chemistry.It holds great potential for diverse fields,particularly in the area of pharmaceuticals.展开更多
Transcranial direct current stimulation(tDCS)is a non-invasive technique that modifies cortical excitability and induces neuroplasticity using low-intensity electrical currents.Nuclear medicine technologies like posit...Transcranial direct current stimulation(tDCS)is a non-invasive technique that modifies cortical excitability and induces neuroplasticity using low-intensity electrical currents.Nuclear medicine technologies like positron emission tomography(PET)and single-photon emission computed tomography(SPECT)can quantify cerebral metabolism and other dynamics.Evidence suggests that combining tDCS with these imaging methods enhances understanding and outcomes for neurological and psychiatric conditions.This review highlights how nuclear medicine can objectively characterize tDCS eff ects,map network modulation,and identify predictive biomarkers.PET and SPECT indicate changes in glucose metabolism and neurotransmitter activity post-tDCS,demonstrating their value in validation.While the co-application of these methodologies is still in conceptual stages,their integration may advance precision neuromodulation and inform rehabilitation strategies.展开更多
Rotating Single-Baseline Interferometer(RSBI)systems have attracted considerable attention for Direct Position Determination(DPD)due to their simplicity and high localization accuracy.Nevertheless,the growing complexi...Rotating Single-Baseline Interferometer(RSBI)systems have attracted considerable attention for Direct Position Determination(DPD)due to their simplicity and high localization accuracy.Nevertheless,the growing complexity of electromagnetic environments has led to scenarios with multiple time-frequency aliased sources,rendering conventional DPD methods for RSBI systems ineffective.Previous studies have predominantly concentrated on deploying antenna arrays and applying related signal-processing techniques for localization.Typically,these approaches necessitate that the number of physical antennas exceeds the number of sources.For RSBI systems already in practical operation,this would entail the installation of additional physical antennas,which implies equipment recycling and hardware upgrades.In numerous cases,such modifications are unfeasible.This paper proposes a novel Relative Offset-based Direct Position Determination(RO-DPD)method for RSBI systems that can handle multiple time-frequency aliased sources.The proposed method overcomes the challenge of simultaneous positioning without requiring hardware modifications by leveraging time accumulation and algorithmic enhancements.The implementation of the method involves three key steps.Firstly,the rotation of the interferometer is synthesized into a virtual Uniform Circular Array(UCA).Secondly,a novel estimation variable,termed relative offset,is introduced.The variable serves as an intermediate parameter to establish correlation equations between the positions of multiple time-frequency aliased sources and the intercepted signals.Thirdly,the relative offset model in the UCA is transformed into a virtual Uniform Linear Array(ULA)model,from which the cost function can be derived via the Spatial Smoothing(SS)MUSIC algorithm.Theoretical analysis and simulation results verify the effectiveness of the proposed method.Compared with traditional approaches,the RO-DPD method maintains the low complexity of RSBI systems while demonstrating robust performance in complex electromagnetic environments.展开更多
The rapid accumulation of spent LiFePO_(4)(LFP)cathodes from retired lithium-ion batteries necessitates the development of effective and environmental-friendly recycling strategies.In this context,direct regeneration ...The rapid accumulation of spent LiFePO_(4)(LFP)cathodes from retired lithium-ion batteries necessitates the development of effective and environmental-friendly recycling strategies.In this context,direct regeneration has emerged as a promising approach for reclaiming LFP cathode materials,offering a streamlined pathway to restore their electrochemical functionality.We report an integrated regeneration protocol that simultaneously repairs the degraded crystal structure and reconstructs the damaged carbon coating in spent LFP.The regenerated cathode material had superfast lithium-ion diffusion kinetics and a stable cathode-electrolyte interface,giving a remarkable rate capability with specific capacities of 122 m Ah g^(-1)at 5C and 106 m Ah g^(-1)at 10C(1C=170 m A g^(-1)).It also maintained capacities of 110.7 m Ah g^(-1)(5C)and 84.1 m Ah g^(-1)(10C)after 400 cycles.It could be used in harsh environments and could be stably cycled at subzero temperatures(-10 and-20°C)and in solid-state electrolyte batteries.Life cycle assessment combined with economic evaluation using the Ever Batt model reveals that this direct regeneration approach has high economic and environmental benefits.展开更多
基金supported by the National Natural Science Foundation of China(Nos.22001026,22171233,22201193)Sichuan Science and Technology Program(No.2023NSFSC0109)+1 种基金the Fundamental Research Funds for the Central Universitiesthe Hundred Talent Program of Sichuan University(No.YJ2021158)。
文摘The linker defect engineering for MOFs is a viable strategy that usually can effectively augment conductivity to further promote charge carrier separation,which is the most excellent conductivity of preserved metal clusters.However,the partially missing photosensitive linker often leads to the diminished light utilization efficiency.As we know,in the linker defect engineering,addressing the lack of photosensitivity while maintaining outstanding conductivity is still in its infancy.In this essay,the linkerdefective NH_(2)-MIL-125 was obtained by adding the glacial acetic acid regulator,subsequently,the excellent light-responsive Pt/CQDs with up-conversion effect was in-situ encapsulated into the enlarged pore space of linker-defective NH_(2)-MIL-125.It is excited that the fabricated dual-functional composite ideally integrates photosensitivity and conductivity for photocatalytic hydrogen evolution and NO elimination.The optimal Pt/CQDs@NM-125-4 exhibited very superior photocatalytic hydrogen evolution(28.75mmol/g),it was 11.63 times as that of the initial NH_(2)-MIL-125(2.47 mmol/g)and 1.4 times as that of the defective NM-125-4(20.46 mmol/g).In addition,the excellent photocatalytic NO removal efficiency was 52.12%for Pt/CQDs@NM-125-4,whereas the original NH_(2)-MIL-125 only reached 30%and the defective NM-125-4 achieved 44.96%.The corresponding optical and electrical characterization based on UV-vis,up-conversion photoluminescence(UCPL),and electrochemical impedance spectroscopy(EIS)etc.demonstrated the defect engineering accelerates the charge carriers transfer via enhancing conductivity,and the in-situ confined up-conversion Pt/CQDs promote the visible light response.Our work presents a feasible avenue to integrate photosensitivity and conductivity via in-situ fabricating excellent lightresponsive Pt/CQDs within linker-defective NH_(2)-MIL-125 for further significantly boosting photocatalytic performance.
基金supported by the National Natural Science Foundation of China(61865003)。
文摘To develop new up-conversion luminescent materials for non-contact optical thermometer with high sensitivity and temperature re solution,a battery of KBaGd(MoO_(4))_(3):Yb^(3+),Ho^(3+)phosphors were fabricated through solid reaction process.The crystal structure,up-conversion luminescence,energy transfer,thermal stability and optical temperature sensing performances were studied in detail.Under 980 nm laser excitation,the KBaGd(MoO_(4))_(3):Yb^(3+),Ho^(3+)phosphor exhibits distinctive emission bands of Ho^(3+)at545,660,and 755 nm,and excellent illuminant performance.Based on the thermally coupled levels(TCLs)of Ho^(3+),both the relative sensitivity(S_(r))and absolute sensitivity(S_(a))display similar change trends,with the highest values of 6.73%/K(@298 K)and 5.69%/K(@298 K),respectively.Furthermore,the highest Saof 13.90%/K(@623 K)and the ultimate Srof 0.62%/K(@298 K)are achieved based on non-TCLs of Ho^(3+).Therefore,KBaGd(MoO_(4))_(3):Yb^(3+),Ho^(3+)phosphor is a promising candidate for self-referenced optical thermometry.
基金Project supported by Hebei Province High-level Talent(Postdoctor)Funding Project(B2022003025)。
文摘For developing and utilizing near-infrared(NIR)energy in sunlight,NaYF4:Yb,Tm(NYFYT)up-conversion Iuminescent powder was combined with Ag_(3)PO_(4)(AP)and Ag_(3)PO_(4)/Pt nanoparticles(AP/PtNPs)as a photocatalyst.Driven by NIR light,NYFYT produces up-conversion emission at 348,364,453 and 478 nm,effectively stimulating the photocatalytic degradation performance of AP and AP/PtNPs,Under xenon lamp irradiation,the apparent rate constants(k)for Ag_(3)PO_(4)/Pt nanoparticles-NaYF4:Yb,Tm(AP/PtNPs-NYFYT)in photocatalytic degradation of rhodamine B(Rh B)and phenol are 5.51 and 12.82 times higher than those of AP and 1.90 and 2.37 times higher than those of AP-NYFYT-50 wt%,respectively.In addition,under 980nm laser irradiation,rate constants are 3.26 and 4.16 times higher than those of AP-NYFYT-50 wt%,respectively.These results indicate that the combination of NYFYT and AP expands the absorption range of the composite photocatalyst and facilitates the NIR-driven photocatalytic process.The introduction of PtNPs effectively prevents the electron-hole recombination and the reduction of Ag+,accelerating the redox reaction and promoting the photocatalytic activity and stability of AP.
基金Project supported by National Natural Science Foundation of China(51962006)the High-level Talents Research Initiation Project of JXUST(205200100545)+1 种基金the Young Elite Scientists Sponsorship Program by CAST(2022QNRC001)Jiangxi Natural Science Foundation of China(20224BAB214029,20232BAB204021)。
文摘Up-conversion(UC)luminescent materials doped with Ln^(3+)ions possess excellent optical properties and extensive applications in the formulation of multifunctional fluorescence ink.Printing technology offers various methods for the preparation of UC fluorescent inks.This study introduced the optical properties of luminescent materials doped with Ln^(3+)ions,including luminescence characteristics and spectral characteristics,which provide a basis for the subsequent printing process.We also reviewed different printing techniques,including direct writing,screen printing,laser printing,inkjet printing,and aerosol jet printing(AJP),developed so far in the literature and explored the printing process of ink characteristics.However,the printing process of inks was explored and their potential for various applications was maximized.Therefore,the printing technology of UC fluorescent inks still faces challenges in different aspects.This review also points out the direction for future in-depth research,which is expected to promote further development and innovation in the field.
基金Supported by National Natural Science Foundation of China(U24B6018,22178243)。
文摘Diesel accounts for over 60%of the products derived from direct coal liquefaction(DCL).Compared to petroleum-based diesel,DCL diesel exhibits a cetane number ranging from 30 to 40,which fails to meet the automotive diesel standard requirement of≥45.Therefore,rapid and accurate analysis of its chemical composition is crucial for property optimization to meet fuel specifications by component blending.Thought traditional methods like gas chromatography offer high accuracy,they are unsuitable for rapid online analysis under industrial conditions.Near-infrared(NIR)spectroscopy can provide advantages in rapid,non-destructive analysis.Its application however,is limited by the complexity of spectral data interpretation.Machine learning(ML)is effective method for extracting valuable information from spectra and establishing high-precision prediction models.This study integrates NIR spectroscopy with ML to construct a spectral-composition database for DCL diesel.Feature extraction was performed using the correlation coefficient and mutual information methods to screen key wavelength variables and reduce data dimensionality.Subsequently,the predictive performance of three ML models—Lasso,SVR and XGBoost—was compared.Results indicate that excluding spectral data with absorbance greater than 1 significantly enhances model accuracy,increasing the test set R^(2) from 0.85 to 0.96.After feature extraction,the optimal number of wavelength variables was reduced to 177,substantially improving computational efficiency.Among the models evaluated,the SVR-MI-0.9 model,based on mutual information feature selection,demonstrated the best performance,achieving training and test set R^(2) values both exceeding 0.98.This model enables precise prediction of paraffin,naphthene,and aromatic hydrocarbon contents.This research provides a robust methodology for intelligent online quality monitoring.An intelligent NIR spectroscopy data analysis software was independently developed based on the established model.Compared with comprehensive two-dimensional gas chromatography,the software reduced the analysis time by over 98%,with an absolute prediction error below 0.2%.Thus,rapid analysis of DCL diesel components was successfully realized.
文摘The efficiency and stability of catalysts for photocatalytic hydrogen evolution(PHE)are largely governed by the charge transfer behaviors across the heterojunction interfaces.In this study,CuO,a typical semiconductor featuring a broad spectral absorption range,is successfully employed as the electron acceptor to combine with CdS for constructing a S-scheme heterojunction.The optimized photocatalyst(CdSCuO2∶1)delivers an exceptional hydrogen evolution rate of 18.89 mmol/(g·h),4.15-fold higher compared with bare CdS.X-ray photoelectron spectroscopy(XPS)and ultraviolet-visible diffuse reflection absorption spectroscopy(UV-vis DRS)confirmed the S-scheme band structure of the composites.Moreover,the surface photovoltage(SPV)and electron paramagnetic resonance(EPR)indicated that the photogenerated electrons and photogenerated holes of CdS-CuO2∶1 were respectively transferred to the conduction band(CB)of CdS with a higher reduction potential and the valence band(VB)of CuO with a higher oxidation potential under illumination,as expected for the S-scheme mechanism.Density-functional-theory calculations of the electron density difference(EDD)disclose an interfacial electric field oriented from CdS to CuO.This built-in field suppresses charge recombination and accelerates carrier migration,rationalizing the markedly enhanced PHE activity.This study offers a novel strategy for designing S-scheme heterojunctions with high light harvesting and charge utilization toward sustainable solar-tohydrogen conversion.
基金National Key Research and Development Program of China(2024YFB4610803)。
文摘The fatigue crack growth rate of a novel Ti-6Al-4V-1Mo titanium alloy,which is developed for laser directed energy deposition technique,was investigated before and after cyclic heat treatment(CHT).Changes in microstructure,fracture surfaces,and crack growth paths were analyzed before and after CHT.Results indicate that in the stable crack growth region,the growth rates for the as-deposited and cyclic heat-treated specimens follow the relationships da/dN=1.8651×10^(−8)(ΔK)^(3.2271)and da/dN=1.4112×10^(−8)(ΔK)^(3.1125),respectively.Compared with that at the as-deposited state,the microstructure after CHT is transformed from a uniform basket-weave microstructure to a dual-phase microstructure consisting of near-sphericalαandβ-transformed matrix phases.The cyclic process also disrupts the continuity of the grain boundaryα(αGB)at the primaryβ-phase grain boundary.The coarsening of primaryαand the disruption ofαGB continuity are the primary factors to release stress concentration and promote crack deflection,thereby decreasing the fatigue crack growth rate.Additionally,the increased occurrence of crack branching,secondary cracking,and crack bridging in cyclic heat-treated specimens further reduces the crack driving force and slows the fatigue crack growth rate.
基金financially supported by the National Natural Science Foundation of China(Nos.22475057 and No.52373262).
文摘Directional three-dimensional carbon-based foams are emerging as highly attractive candidates for promising electromagnetic wave absorbing materials(EWAMs)thanks to their unique architecture,but their construction usually involves complex procedures and extremely depends on unidirectional freezing technique.Herein,we propose a groundbreaking approach that leverages the assemblies of salting-out protein induced by ammonium metatungstate(AM)as the precursor,and then acquire directional three-dimensional carbon-based foams through simple pyrolysis.The electrostatic interaction between AM and protein ensures well dispersion of WC_(1−x)nanoparticles on carbon frameworks.The content of WC_(1−x)nanoparticles can be rationally regulated by AM dosage,and it also affects the electromagnetic(EM)properties of final carbon-based foams.The optimized foam exhibits exceptional EM absorption performance,achieving a remarkable minimum reflection loss of−72.0 dB and an effective absorption bandwidth of 6.3 GHz when EM wave propagates parallel to the directional pores.Such performance benefits from the synergistic effects of macroporous architecture and compositional design.Although there is a directional dependence of EM absorption,radar stealth simulation demonstrates that these foams can still promise considerable reduction in radar cross section with the change of incident angle.Moreover,COMSOL simulation further identifies their good performance in preventing EM interference among different electronic components.
基金supported in part by the National Key R&D Program of China(No.2024YFA1610700)the National Natural Science Foundation of China(No.12475147)。
文摘The Cooling-Storage-Ring External-target Experiment(CEE)at the Heavy Ion Research Facility in Lanzhou(HIRFL)is designed to study the properties of nuclear matter created in heavy-ion collisions at beam energies from a few hundred MeV/u up to 1 GeV/u.It aims to facilitate research on the quantum chromodynamics(QCD)phase structure in the high-baryondensity region.Collective flow is a fundamental observable in heavy-ion collision experiments,providing information on the bulk properties of the produced matter.Although the standard event plane method has been widely used to measure collective flow,it is still important to validate and optimize this method for the CEE spectrometer.In this paper,we study the experimental procedures for measuring directed flow in^(238)U+^(238)U collisions at 500 MeV/u,using event planes reconstructed by Multi-Wire Drift Chamber and Zero Degree Calorimeter,respectively.Jet AA Microscopic(JAM)transport generator is used to generate events,and the detector response is simulated by the CEE Fast Simulation(CFS)package.Finally,the optimal kinematic region for proton directed flow measurements is discussed for the future CEE experiment.
基金supported by the National Nature Science Foundation of China(Grant Nos.12475019 and 12073056)the Major National Science and Technology Project of China(Grant No.BX2024B054)+1 种基金National Lab of Solid State Microstructure of Nanjing University(Grant Nos.M35040,M35053,and M37014)the Natural Science Foundation of Shandong Province(Grant No.ZR2024MA038)。
文摘For a multi-frequency non-reciprocal optical device,we first realize multi-frequency optical non-reciprocal transmission using a non-Hermitian multi-mode resonator array.Practically,multi-frequency operation can add channels to the non-reciprocal optical device and the non-reciprocity can route optical signals and prevent the reverse flow of noise.Using the Scully–Lamb model and gain saturation effect,we accomplish dual-frequency non-reciprocal transmission by introducing nonlinearity into a linear array of four-mode resonators.The accomplishment is directly demonstrated by the non-reciprocal transmission phenomena present in the non-divergent peaks.For example,a directional cyclic amplifier is constructed with non-reciprocal units.Regarding potential applications,non-reciprocal optical systems can be employed in dual-frequency control,parallel information processing,photonic integrated circuits,optical devices and so on.
文摘Objective:To explore the interventional room nursing and its application effects in patients with ischemic stroke treated with tirofiban combined with direct thrombectomy.Methods:A total of 61 patients with ischemic stroke admitted to our hospital from June 2024 to June 2025 were selected and divided into two groups using the red and blue ball method:the control group(n=30,receiving routine interventional room nursing)and the observation group(n=31,receiving additional tirofiban medication-specific nursing+individualized interventional nursing on the basis of routine nursing).The cerebral hemodynamic indicators,adverse reactions,effectiveness of complication nursing,and nursing satisfaction were compared between the two groups.Results:After 7 days of treatment,the observation group had lower cerebrovascular peripheral resistance and higher mean blood flow velocity and mean blood flow volume compared to the control group(all p<0.05).The observation group had a higher effectiveness rate of complication nursing than the control group,with a statistically significant difference(p<0.05).The nursing satisfaction in the observation group(96.77%)was higher than that in the control group(80.00%),with a statistically significant difference(χ^(2)=4.223,p=0.040<0.05).Conclusion:Tirofiban combined with direct thrombectomy can significantly improve cerebral hemodynamics,enhance the effectiveness of complication nursing,and increase patient satisfaction in patients with ischemic stroke.
文摘BACKGROUND Drug utilization research has an important role in assisting the healthcare administration to know,compute,and refine the prescription whose principal objective is to enable the rational use of drugs.Research in developing nations relating to the cost of treatment is scarce when compared with developed countries.Thus,the drug utilization research studies from developing nations are most needed,and their number has been growing.AIM To evaluate patterns of utilization of antipsychotic drugs and direct medical cost analysis in patients newly diagnosed with schizophrenia.METHODS The present study was observational in type and based on a retrospective cohort to evaluate patterns of utilization of antipsychotic drugs using World Health Organization(WHO)core prescribing indicators and anatomical therapeutic chemical/defined daily dose indicators.We also calculated direct medical costs for a period of 6 months.RESULTS This study has found that atypical antipsychotics are the mainstay of treatment for schizophrenia in every age group and subcategories of schizophrenia.The evaluation based on WHO prescribing indicators showed a low average number of drugs per prescription and low prescribing frequency of antipsychotics from the National List of Essential Medicines 2015 and the WHO Essential Medicines List 2019.The total mean drug cost of our study was 1396 Indian rupees.The total mean cost due to the investigation in our study was 1017.34 Indian rupees.Therefore,the total mean direct medical cost incurred on patients in our study was 4337.28 Indian rupees.CONCLUSION The information from the present study can be used for reviewing and updating treatment policy at the institutional level.
基金supported in part by the National Natural Science Foundation of China under Grants 62025110,62271093sponsored by Natural Science Foundation of Chongqing,China,under Grant CSTB2023NSCQ-LZX0108.
文摘Efficient energy utilization in covert communication sustains covertness while assuring communication quality and efficiency.This paper investigates covert communication energy efficiency(EE)in direct uplink satellite-ground communications,focusing on enhancing system EE via optimized transmit beamforming and satellite orbit altitude selection.This paper first establishes an optimization problem to maximize system EE in a direct uplink satelliteground covert communication scenario.To solve this non-convex optimization problem,it is decomposed into two subproblems and solved using the successive convex approximation(SCA)method.Based on the above methods,this paper proposes an overall iterative optimization algorithm.Simulation results demonstrate that the proposed algorithm surpasses the conventional baseline algorithms in terms of system EE.Furthermore,they elucidate the correlation between the amount of information received by the receiver and the variations in the satellite’s orbital altitude.
基金supported by the National Natural Science Foundation of China(62373317)the Tianshan Talent Training Program(2022TSYCCX0013)+3 种基金the Key Project of Natural Science Foundation of Xinjiang(2021D01D10)the Basic Research Foundation for Universities of Xinjiang(XJEDU2023P023)the Xinjiang Key Laboratory of Applied Mathematics(XJDX1401)the Intelligent Control and Optimization Research Platform in Xinjiang University.
文摘This paper is dedicated to fixed-time passivity and synchronization for multi-weighted spatiotemporal directed networks.First,to achieve fixed-time passivity,a type of decentralized power-law controller is developed,in which only one parameter needs to be adjusted in the power-law terms;this greatly decreases the inconvenience of parameter adjustment.Second,several fixed-time passivity criteria with LMI forms are derived by using a Gauss divergence theorem to deal with the spatial diffusion of nodes and by applying the Hölder’s inequality to dispose rigorously the power-law term greater than one in the designed control scheme;this improves the previous theoretical analysis.Additionally,the fixed-time synchronization of spatiotemporal directed networks with multi-weights is addressed as a direct result of fixed-time strict passivity.Finally,a numerical example is presented in order to show the validity of the theoretical analysis.
基金financially supported by the National Key Research and Development Program of China(Nos.2024YFB4607402 and 2016YFC1100502)the National Natural Science Foundation of China(Nos.51673208 and 61975213)。
文摘Biopolymeric nanocomposites have attracted considerable attention because of their biocompatibility,biodegradability,and unique physicochemical properties.It is essential to manufacture three-dimensional(3D)biocompatible micro/nanostructures using biopolymeric nanocomposites.Herein,we demonstrate the high-fidelity fabrication of biocompatible 3D features with sub-50 nm resolution using femtosecond laser direct writing(FsLDW)of a biopolymeric nanocomposite composed of egg white and sulfonated graphene(S-graphene).The biopolymer nanocomposite acts as a negative photoresist suitable for water-based lithography.The introduction of S-graphene not only dramatically lowered the laser power threshold but also significantly modulated the morphology of the 3D features constructed by FsLDW.Microstructures with porous,rough,or smooth morphologies were obtained by optimizing the S-graphene concentration and laser scanning speed.The fabricated egg-white/S-graphene microstructures exhibited biocompatibility and environmental degradability.Egg white/S-graphene was also employed to fabricate diffractive gratings with superior optical quality.This study provides a promising method to manufacture biocompatible 3D features with controllable morphology,which has potential applications in biological and photonic fields.
基金supported in part by the Natural Science Foundation of China(62273227,92367203)the Open Research Project of the State Key Laboratory of Industrial Control Technology,China(ICT2024B68)。
文摘This article studies the consensus problem with directed graphs for general linear multi-agent systems.New distributed state-feedback protocols with dynamic event-triggered(DET)mechanisms are proposed for directed graphs that are strongly connected and weight-balanced,general strongly connected,and have spanning trees,respectively.It is proven that strictly positive minimum inter-event times(MIETs)are ensured using the designed DET mechanisms.Several numerical examples are presented to illustrate the effectiveness of the theoretical results.Compared with existing results,our results have the following merits:1)DET mechanisms are designed to determine the sampling instants,which can reduce the communication frequency between agents compared with static mechanisms;2)We focus on the consensus problem on directed graphs,which is more general than existing related results on undirected graphs;3)The existence of positive MIETs is shown to be guaranteed by the designed DET sampling strategies while existing related results can only exclude Zeno behavior.
基金support from the National Key Research and Development Program of China(No.2023YFA0914100/2023YFA0914102)the National Natural Science Foundation of China(Nos.22077029 and 22034002)+2 种基金the Science Fund for Distinguished Young Scholars of Hunan Province(No.2021JJ10034)support from the National Natural Science Foundation of China(No.22276049)M.M.acknowledge the support from the National Natural Science Foundation of China(No.22276050).
文摘We report for the first time the combination of directed evolution focused on enhancing and reversing the stereoselectivity of an enzyme with Cu(I)-mediated click chemistry(CuAAC),providing an asymmetric click approach for versatile chiral triazoles products.In this study,the halohydrin dehalogenase HheG was used as the enzyme which was evolved to induce a stereoselective ring-opening reaction of cyclic epoxides in the presence of NaN3 with the formation of chiral azido products.Two mutants of opposite stereopreference were generated,which convert cyclohexene oxide as well as cycloheptene oxide to(1S,2S)-2-azidocyclohexanol,(1R,2R)-2-azidocyclohexanol,(1S,2S)-2-azidocycloheptanol and(1R,2R)-2-azidocycloheptanol with essentially high stereoselectivity.The chiral products were then subjected to CuAAC in reactions with structurally different alkynes.Since HheG was found to be compatible with Cu(I),the process was also performed successfully in a unique 2-step one-pot process leading to various chiral triazoles.In order to understand the enhancement and reversal of the evolved enantioselectivity,QM and MD computations were performed.This approach harnesses the modifiability and high stereoselectivity of the evolved biocatalysts in combination with click chemistry.It holds great potential for diverse fields,particularly in the area of pharmaceuticals.
文摘Transcranial direct current stimulation(tDCS)is a non-invasive technique that modifies cortical excitability and induces neuroplasticity using low-intensity electrical currents.Nuclear medicine technologies like positron emission tomography(PET)and single-photon emission computed tomography(SPECT)can quantify cerebral metabolism and other dynamics.Evidence suggests that combining tDCS with these imaging methods enhances understanding and outcomes for neurological and psychiatric conditions.This review highlights how nuclear medicine can objectively characterize tDCS eff ects,map network modulation,and identify predictive biomarkers.PET and SPECT indicate changes in glucose metabolism and neurotransmitter activity post-tDCS,demonstrating their value in validation.While the co-application of these methodologies is still in conceptual stages,their integration may advance precision neuromodulation and inform rehabilitation strategies.
基金partially supported by the National Natural Science Foundation of China(Nos.61901494,62101563)。
文摘Rotating Single-Baseline Interferometer(RSBI)systems have attracted considerable attention for Direct Position Determination(DPD)due to their simplicity and high localization accuracy.Nevertheless,the growing complexity of electromagnetic environments has led to scenarios with multiple time-frequency aliased sources,rendering conventional DPD methods for RSBI systems ineffective.Previous studies have predominantly concentrated on deploying antenna arrays and applying related signal-processing techniques for localization.Typically,these approaches necessitate that the number of physical antennas exceeds the number of sources.For RSBI systems already in practical operation,this would entail the installation of additional physical antennas,which implies equipment recycling and hardware upgrades.In numerous cases,such modifications are unfeasible.This paper proposes a novel Relative Offset-based Direct Position Determination(RO-DPD)method for RSBI systems that can handle multiple time-frequency aliased sources.The proposed method overcomes the challenge of simultaneous positioning without requiring hardware modifications by leveraging time accumulation and algorithmic enhancements.The implementation of the method involves three key steps.Firstly,the rotation of the interferometer is synthesized into a virtual Uniform Circular Array(UCA).Secondly,a novel estimation variable,termed relative offset,is introduced.The variable serves as an intermediate parameter to establish correlation equations between the positions of multiple time-frequency aliased sources and the intercepted signals.Thirdly,the relative offset model in the UCA is transformed into a virtual Uniform Linear Array(ULA)model,from which the cost function can be derived via the Spatial Smoothing(SS)MUSIC algorithm.Theoretical analysis and simulation results verify the effectiveness of the proposed method.Compared with traditional approaches,the RO-DPD method maintains the low complexity of RSBI systems while demonstrating robust performance in complex electromagnetic environments.
基金financial support from the National Key R&D Program of China(2022YFB2402600)the National Natural Science Foundation of China(52372250,52125105,52173242)+1 种基金Shenzhen Science and Technology Planning Project(RCYX20221008092850072,JSGG20220831104004008,KJZD20230923113859006,JCYJ20220531100405012,KJZD20241122161900001)Science and Technology Planning Project of Guangdong Province(2024A1515030076)。
文摘The rapid accumulation of spent LiFePO_(4)(LFP)cathodes from retired lithium-ion batteries necessitates the development of effective and environmental-friendly recycling strategies.In this context,direct regeneration has emerged as a promising approach for reclaiming LFP cathode materials,offering a streamlined pathway to restore their electrochemical functionality.We report an integrated regeneration protocol that simultaneously repairs the degraded crystal structure and reconstructs the damaged carbon coating in spent LFP.The regenerated cathode material had superfast lithium-ion diffusion kinetics and a stable cathode-electrolyte interface,giving a remarkable rate capability with specific capacities of 122 m Ah g^(-1)at 5C and 106 m Ah g^(-1)at 10C(1C=170 m A g^(-1)).It also maintained capacities of 110.7 m Ah g^(-1)(5C)and 84.1 m Ah g^(-1)(10C)after 400 cycles.It could be used in harsh environments and could be stably cycled at subzero temperatures(-10 and-20°C)and in solid-state electrolyte batteries.Life cycle assessment combined with economic evaluation using the Ever Batt model reveals that this direct regeneration approach has high economic and environmental benefits.
