In order to better describe the phenomenon of biological invasion,this paper introduces a free boundary model of biological invasion.Firstly,the right free boundary is added to the equation with logistic terms.Secondl...In order to better describe the phenomenon of biological invasion,this paper introduces a free boundary model of biological invasion.Firstly,the right free boundary is added to the equation with logistic terms.Secondly,the existence and uniqueness of local solutions are proved by the Sobolev embedding theorem and the comparison principle.Finally,according to the relevant research data and contents of red fire ants,the diffusion area and nest number of red fire ants were simulated without external disturbance.This paper mainly simulates the early diffusion process of red fire ants.In the early diffusion stage,red fire ants grow slowly and then spread over a large area after reaching a certain number.展开更多
Comprehensive utilization of phosphogypsum(PG)has attracted much attention,especially for the recovery of rare earth elements(REEs)and gypsum due to the issues of stockpile,environmental pollution,and waste of associa...Comprehensive utilization of phosphogypsum(PG)has attracted much attention,especially for the recovery of rare earth elements(REEs)and gypsum due to the issues of stockpile,environmental pollution,and waste of associated resources.Traditional utilization methods suffered the issues of low REEs leaching efficiency,huge amount of CaSO_(4)saturated wastewater and high recovery cost.To solve these issues,this study investigated the occurrence of REEs in PG and the leaching of REEs.The results show that REEs in PG are in the forms of(1)REEs mineral inclusions,(2)REEs isomorphous substitution of Ca^(2+)in gypsum lattice,(3)dispersed soluble REEs salts.Acid leaching results demonstrate that(1)the dissolution of gypsum matrix is the control factor of REEs leaching;(2)H_(2)SO_(4)is a promising leachant considering the recycle of leachate;(3)the gypsum matrix suffers a recrystallization during the acid leaching and releases the soluble REEs from PG to aqueous solution.For the recovery of the undissolved REEs mineral inclusions,wet sieving concentrated 37.1 wt%of the REEs in a 10.7 wt%mass,increasing REEs content from 309 to 1071 ppm.Finally,a green process combining gravity separation and hydrometallurgy is proposed.This process owns the merits of wastewater free,considerable REEs recovery(about 10%increase compared with traditional processes),excellent gypsum purification(>95 wt%CaSO_(4)·2H_(2)O,with<0.06 wt%of soluble P_(2)O_(5) and<0.015 wt%of soluble F)and reagent saving(about 2/3less reagent consumption than non-cyclical leaching).展开更多
Owing to their low toxicity and remarkable stability, perovskites based on antimony and bismuth have garnered significant interest in recent years. However, A_(3)B_(2)X_(9) perovskite materials derived from antimony a...Owing to their low toxicity and remarkable stability, perovskites based on antimony and bismuth have garnered significant interest in recent years. However, A_(3)B_(2)X_(9) perovskite materials derived from antimony and bismuth face several challenges, including excessively wide band gaps, elevated defect densities, and suboptimal film quality, all of which hinder advancements in device efficiency. While extensive studies have been undertaken to investigate the effects of modulating the A-site and X-site elements in lead-free A_(3)B_(2)X_(9) perovskites, there remains a notable scarcity of reports addressing the impact of modifications to the B-site element. In this study, we investigated the alloying of antimony and bismuth within the 2D Cs_(3)B_(2)I_(6)Br_(3) perovskite. By systematically varying the ratios of two elements, we found that the incorporation of both antimony and bismuth at the B-site significantly enhances the quality of the perovskite films. Our findings indicate that a 1 : 1 ratio of antimony to bismuth produces the densest films, the highest photoluminescence intensity, and superior photovoltaic performance. Ultimately,the devices fabricated using this optimal ratio achieved an open-circuit voltage(VOC) of 1.01 V and a power conversion efficiency(PCE) of 0.645%.展开更多
Let G be a group.The family of all sets which are closed in every Hausdorf group topology of G form the family of closed sets of a T_(1) topology M_(G) on G called the Markov topology.Similarly,the family of all algeb...Let G be a group.The family of all sets which are closed in every Hausdorf group topology of G form the family of closed sets of a T_(1) topology M_(G) on G called the Markov topology.Similarly,the family of all algebraic subsets of G forms a family of closed sets for another T_(1)topology Z_(G) on G called the Zarski topology.A subgroup H of G is said to be Markov(resp.Zarski)embedded if the equality M_(G|H)=M_(H)(resp.Z_(G|H)=Z_(H))holds.I's proved that an abirary subgroup of a free group is both Zariski and Markov embedded in it.展开更多
Labor provisions have become a fundamental trade rule in regional and bilateral trade agreements.Although China’s legislation on pilot Free Trade Zones includes content related to labor protection,it primarily aligns...Labor provisions have become a fundamental trade rule in regional and bilateral trade agreements.Although China’s legislation on pilot Free Trade Zones includes content related to labor protection,it primarily aligns with labor indicators in“Doing Business”,the assessment of business situations issued by the World Bank.It differs from the labor rights protection focus emphasized in trade agreements.The latest strategic documents issued by the State Council of China have addressed this issue to fully achieve the goal of aligning Free Trade Zones with high-standard trade agreements.Building on the development of Free Trade Zone legislation and domestic labor law governance,China should proactively explore a tailored approach to labor provisions in Free Trade Agreements.In this approach,it should explicitly define the“baseline”and“ceiling”for labor provisions during negotiations and,within this framework,establish benchmarks for labor rights protection,enforcement mechanisms,and cross-border regulatory mechanisms suited to the specific conditions of the agreement parties.展开更多
Silicon,a leading candidate for electrode material for lithium-ion batteries,has garnered significant attention.During the initial lithiation process,the alloying reaction between silicon and lithium transforms the pr...Silicon,a leading candidate for electrode material for lithium-ion batteries,has garnered significant attention.During the initial lithiation process,the alloying reaction between silicon and lithium transforms the pristine silicon microstructure from crystalline to amorphous,resulting in plastic deformation of the amorphous phase.This study proposes the free volume theory to develop a fully coupled Cahn-Hilliard phase-field model that integrates viscoplastic deformation,free volume evolution,and diffusion.This model investigates the chemophysical phenomenon of self-limiting behavior occurring during the initial lithiation of silicon anodes.Unlike most existing models,the proposed model considers free volume-dependent diffusion using a physically-based approach.The model’s temporal variation in the lithiated phase thickness aligns well with experimental results,confirming the model’s accuracy.Stress field calculations reveal the coexistence of compressive and tensile stresses within the lithiated phase,which may not cause the limiting effect under the frame of the stress-induced diffusion.Analyses indicate that high effective stress increases free volume,enhancing lithium diffusion and augmenting the diffusion coefficient.Reducing the diffusion coefficient in the lithiated phase due to free volume evolution is the primary cause of self-limiting lithiation.展开更多
As an important strategic fulcrum for China’s new round of opening-up,the Hainan Free Trade Port provides broad space for achieving high-quality development with its unique policy advantages and financial resources.I...As an important strategic fulcrum for China’s new round of opening-up,the Hainan Free Trade Port provides broad space for achieving high-quality development with its unique policy advantages and financial resources.In this context,integrating blockchain technology into the construction of the free trade port can not only help enhance the innovation and competitiveness of the talent cultivation system but also promote the coordinated development of the real economy and the industrial system.Based on the core characteristics of blockchain technology,such as“decentralization,traceability,and high credibility”,this paper focuses on the common problems in the cultivation of composite talents in current vocational colleges,including an imperfect school-enterprise cooperation guarantee mechanism,a lack of teaching resources,weak teaching staff,and insufficient practical conditions.It proposes a new idea of introducing blockchain technology into the vocational education system.Through the research on the cultivation model of composite-skilled talents in vocational colleges in the context of“blockchain+”,this paper aims to promote the in-depth integration of vocational education in vertical and horizontal aspects,and further promote the systematic,standardized,and high-quality development of composite talent cultivation.展开更多
Quantum digital signature(QDS)can guarantee the information-theoretical security of a signature with the fundamental laws of quantum physics.However,most current QDS protocols do not take source security into account,...Quantum digital signature(QDS)can guarantee the information-theoretical security of a signature with the fundamental laws of quantum physics.However,most current QDS protocols do not take source security into account,leading to an overestimation of the signature rate.In this paper,we propose to utilize Hong–Ou–Mandel interference to characterize the upper bound of the source imperfections,and further to quantify information leakage from potential side-channels.Additionally,we combine decoy-state methods and finite-size analysis in analyzing the signature rate.Simulation results demonstrate the performance and feasibility of our approach.Our current work can improve the practical security of QDS systems,thereby promoting their further networked applications.展开更多
Too much screen time is bad for your brain and body.It can also waste your time.So,try to spend less time on scree ns.Changing habits is not easy,but you can do it.Use an app to track your time on your smartphone.Do y...Too much screen time is bad for your brain and body.It can also waste your time.So,try to spend less time on scree ns.Changing habits is not easy,but you can do it.Use an app to track your time on your smartphone.Do you waste a lot of time on some ofyour phone apps?Take them off or set time limits for them.Less screen time means more free time for other things.Go hiking,visit a museum or try a new hobby.Use your phone less and appreciate life more.展开更多
The high temporal and spatial coherence of free electron lasers(FELs)reduces the uniformity of the illumination field,leading to scattering effects that blur the edges of patterns,resulting in diminished accuracy and ...The high temporal and spatial coherence of free electron lasers(FELs)reduces the uniformity of the illumination field,leading to scattering effects that blur the edges of patterns,resulting in diminished accuracy and clarity.Traditional imaging models regard the light source as fully incoherent,making it difficult to assess the impact of partially coherent light fields on imaging.If FELs are used in imaging systems,their coherence must be considered.To address this issue,this study explores the relationship between coherence,imaging quality and speckle contrast through a simulation method based on random phases.The method divides the light beam into temporal and spatial coherence cells,analyzes their interactions,and simulates imaging results under different coherence conditions.Additionally,speckle patterns for various illumination modes are calculated to evaluate their effects on speckle contrast and illumination uniformity.The results indicate that under different illumination modes,illumination uniformity decreases as coherence increases,while speckle contrast increases with higher coherence.In terms of imaging quality,higher coherence leads to an increase in both line edge roughness(LER)and line width roughness(LWR),thereby reducing the imaging quality.Additionally,the narrower the line width,the greater the impact of coherence on the imaging quality,resulting in poorer imaging performance.展开更多
With the development of global economic integration,building a world-class facilitating business environment has become an urgent need for Hainan Free Trade Port.To solve the existing problems in financial policies,le...With the development of global economic integration,building a world-class facilitating business environment has become an urgent need for Hainan Free Trade Port.To solve the existing problems in financial policies,legal supervision,and other aspects,this paper takes Hainan Free Trade Port as an example to analyze and study its institutional integration strategy for creating a world-class facilitating business environment.The specific integration strategies are summarized to promote the internationalization and facilitation of the business environment of Hainan Free Trade Port and promote the high development of the local economy.展开更多
A thermionic gun is endowed with a long bunch tail,which presents challenges for the compact terahertz free electron laser(FEL)facility at the Huazhong University of Science and Technology.Owing to a large energy spre...A thermionic gun is endowed with a long bunch tail,which presents challenges for the compact terahertz free electron laser(FEL)facility at the Huazhong University of Science and Technology.Owing to a large energy spread,the tail particles do not contribute to the radiation.In the original design,an x-direction slit is used in the dispersive section of the transport line to remove the tail particles.This paper presents an improved scheme to remove the tail by introducing an RF beam chopper system at the exit of the electron gun,to prevent a significant number of tail particles from entering the linac.The facility remains compact while effectively removing the tail of the bunch.The parameters of the beam chopper system are designed.Bunch parameters and radiation performance are analyzed via a start-to-end simulation.The findings indicate that 43%of the particles can pass through the beam chopper system for subsequent acceleration and transport,which saves the RF power,reduces beam loss in the linac,reduces background noise,and suppresses the sideband instability.Simultaneously,the beam chopper system causes an increase in beam emittance,energy spread,and an offset in the center of the bunch.These effects can be mitigated by a solenoid,linac,and steering coils.The simulation results for the FEL show that the micro-pulse energy is greater than 1.1μJ in the frequency range of 2.8-9.7 THz,and the maximum micro-pulse energy is 1.28μJ.展开更多
Nucleotide binding domain,leucine-rich repeat,and pyrin domain-containing 3(NLRP3)is an NLR-protein family member that can be activated by diverse exogenous and endogenous stimuli but without direct binding of any of ...Nucleotide binding domain,leucine-rich repeat,and pyrin domain-containing 3(NLRP3)is an NLR-protein family member that can be activated by diverse exogenous and endogenous stimuli but without direct binding of any of these pathogen ligands.Biological studies show that inactive NLRP3 is usually in an as-sembly state and its activation requires a kinase protein,NEK7.However,our re-cent computational studies as well as other biological investigations have demonstrated that NEK7 does not play a significant role in the activation of NLRP3 assembly and activation.In-stead,biological studies suggest that NEK7 is essential in the dissociation of inactive NLRP3 assemblies.Despite extensive research,the dissociation mechanism of the inactive NLRP3 as-sembly remains largely elusive.In this work,an improved MM-PBSA method is applied to the protein-protein binding free energies in the inactive NLRP3 decamer.Combined with the po-tential mean force(PMF)computation for the 0°→5°conformational change,the standard free-energy change,ΔG^(0)is calculated for NEK7-driven association of the inactive NLRP3 de-camer.Our calculations show that in the absence of NEK7,the dissociation of the inactive NLRP3 decamer is an energetically unfavorable process(ΔG^(0)=99.69 kcal/mol),whereas upon NEK7 binding,the overall standard free energy differenceΔG^(0)=-24.21 kcal/mol is obtained for the inactive NLRP3 decamer dissociation.The free-energy difference calcula-tions in this work also disclose an energetically optimized dissociation pathway,along which the inactive NLRP3 decamer is disunited by a one-by-one dissociation mechanism.展开更多
Background:Free flap transplantation has emerged as a prevalent technique in reconstructive surgery for patients with oral cancer.Postoperative monitoring of flap perfusion is critical for flap survival,necessitating ...Background:Free flap transplantation has emerged as a prevalent technique in reconstructive surgery for patients with oral cancer.Postoperative monitoring of flap perfusion is critical for flap survival,necessitating early detection and timely intervention.Developing a monitoring approach that is highly sensitive,specific,noninvasive,continuous,and cost-effective is crucial for accurately assessing flap perfusion and informing clinical decisions.Methods:From April 2024 to December 2024,20 patients with oral tumors requiring flap transplantation were enrolled at the Ninth People’s Hospital affiliated to Shanghai Jiao Tong University School of Medicine.Continuous monitoring of various free flaps was performed utilizing a transcutaneous blood gas analyzer,both before and after surgery.This approach allowed for real-time measurement of transcutaneous partial pressure of oxygen(TcPO_(2))and transcutaneous partial pressure of carbon dioxide(TcPCO_(2)),facilitating the evaluation of perfusion dynamics across various free flap types.Results:After free flap transplantation,a reduction in blood supply resulted in a rapid decline in TcPO_(2)(to below 10 mmHg),accompanied by a gradual increase in TcPCO_(2),peaking at 135 mmHg.Following vascular anastomosis and blood flow restoration,TcPO_(2)and TcPCO_(2)exhibited opposite trends.Statistical analysis revealed no significant differences in TcPO_(2)and TcPCO_(2)measurements among the various flap types(P<0.05),indicating a consistent pattern of change across all flaps.Conclusion:The transcutaneous blood gas analyzer proves to be a reliable method for monitoring free flap perfusion.Dynamic changes in TcPO_(2)and TcPCO_(2)effectively reflect blood supply status,enabling early detection of vascular compromise and potentially enhancing flap preservation outcomes.展开更多
The dynamic behavior of high-speed craft navigating through variable sea states plays a pivotal role in ensuring maritime safety.However,many existing simulation approaches rely on linear or overly simplified represen...The dynamic behavior of high-speed craft navigating through variable sea states plays a pivotal role in ensuring maritime safety.However,many existing simulation approaches rely on linear or overly simplified representations of the marine environment,thereby limiting the fidelity of motion predictions.This study explores the motion characteristics of a 4.5-t high-speed vessel by conducting fully coupled numerical simulations using the STAR-CCM+software.The analysis considers both calm and varying sea conditions,incorporating fluctuations in wave height,wavelength,and wind speed to reflect more realistic operating scenarios.Simulation results reveal that the vessel’s hydrodynamic response is highly sensitive to changes in sea state.As conditions deteriorate,the free surface becomes increasingly complex,with higher wave amplitudes and more pronounced interactions between the waves generated by the vessel and those imposed by the external environment.These effects lead to significant increases in roll,pitch,heave,and sway motions,thereby imposing greater demands on the vessel’s dynamic stability and operational safety.Furthermore,both hydrodynamic resistance and propulsive thrust exhibit notable dependence on sea state and vessel speed.Total resistance generally increases with rougher sea conditions,while thrust tends to rise with increasing forward speed.Under calm or mildly disturbed waters,a Froude number(Fr)of 0.5 appears to offer an optimal balance for initiating and controlling primary motions such as roll,pitch,heave,and sway.Conversely,in more challenging conditions-such as those represented by a Sea State 3-effective motion control is better achieved at a higher Froude number of approximately 1.0.展开更多
Verification and validation(V&V)is a helpful tool for evaluating simulation errors,but its application in unsteady cavitating flow remains a challenging issue due to the difficulty in meeting the requirement of an...Verification and validation(V&V)is a helpful tool for evaluating simulation errors,but its application in unsteady cavitating flow remains a challenging issue due to the difficulty in meeting the requirement of an asymptotic range.Hence,a new V&V approach for large eddy simulation(LES)is proposed.This approach offers a viable solution for the error estimation of simulation data that are unable to satisfy the asymptotic range.The simulation errors of cavitating flow around a projectile near the free surface are assessed using the new V&V method.The evident error values are primarily dispersed around the cavity region and free surface.The increasingly intense cavitating flow increases the error magnitudes.In addition,the modeling error magnitudes of the Dynamic Smagorinsky-Lilly model are substantially smaller than that of the Smagorinsky-Lilly model.The present V&V method can capture the decrease in the modeling errors due to model enhancements,further exhibiting its applicability in cavitating flow simulations.Moreover,the monitoring points where the simulation data are beyond the asymptotic range are primarily dispersed near the cavity region,and the number of such points grows as the cavitating flow intensifies.The simulation outcomes also suggest that the re-entrant jet and shedding cavity collapse are the chief sources of vorticity motions,which remarkably affect the simulation accuracy.The results of this study provide a valuable reference for V&V research.展开更多
In this paper,we consider the plasma-vacuum interface problem in a cylindrical tube region impressed by a special background magnetic field.The interior region is occupied with plasma,which is governed by the incompre...In this paper,we consider the plasma-vacuum interface problem in a cylindrical tube region impressed by a special background magnetic field.The interior region is occupied with plasma,which is governed by the incompressible inviscid and resistive MHD system without damping term.The exterior vacuum region is governed by the so-called the“pre-Maxwell equations”.And on the free interface,additionally,the effect of surface tension is taken into account.The original region can be transformed into a horizontally periodic slab through the cylindrical coordinate transformation,which will be impressed by a uniform nonhorizontal magnetic field.Appending with the appropriate physical boundary conditions,the global well-posedness of the problem is established by the energy method.展开更多
In this study,the free vibration of a piezoelectric semiconductor(PS)composite structure composed of a PS layer,a fractional viscoelastic layer,and an elastic substrate with simply-supported boundary conditions is inv...In this study,the free vibration of a piezoelectric semiconductor(PS)composite structure composed of a PS layer,a fractional viscoelastic layer,and an elastic substrate with simply-supported boundary conditions is investigated.The fractional derivative Zener model is used to establish the constitutive relation of the viscoelastic layer.The first-order shear deformation theory and Hamilton's principle are used to derive the motion equations of the present problem.The frequency parameter is numerically resolved with the Newton-Raphson method through the eigenvalue equation.The effects of either geometric parameters,carrier density,and electric voltage applied on the surface of the composite structure or the fractional order of the Zener model on both the natural frequency and loss factor are discussed,and some interesting conclusions are drawn.This work will be helpful for designing and manufacturing PS materials and structures.展开更多
The construction project of a non-super high-rise public building in Guangzhou’s Nansha Free Trade Zone faces unique challenges.The project established a full-cycle technical management system,encompassing technical ...The construction project of a non-super high-rise public building in Guangzhou’s Nansha Free Trade Zone faces unique challenges.The project established a full-cycle technical management system,encompassing technical management across various sectors and BIM collaboration.Simultaneously,it introduced advanced technical management such as deep foundation pits and core tube construction,along with a risk management system and special weather response strategies.Through these measures,the project achieved numerous significant results,forming a unique management paradigm that offers valuable insights for similar engineering projects.展开更多
Laparoscopic sleeve gastrectomy(LSG),as an effective treatment for morbid obesity and its metabolic complications,exerts its therapeutic effects by significantly reducing body weight and improving metabolic disorders....Laparoscopic sleeve gastrectomy(LSG),as an effective treatment for morbid obesity and its metabolic complications,exerts its therapeutic effects by significantly reducing body weight and improving metabolic disorders.Its core mechanisms involve multi-level regulation of free fatty acid(FFA)metabolism and chronic low-grade inflammatory states(represented by tumor necrosis factor-alpha,TNF-α).This paper systematically reviews the direct impact of LSG on FFA dynamics including lipolysis,tissue uptake,and oxidation,as well as the molecular pathways through which it indirectly regulates TNF-αby reducing adipose tissue inflammation,improving intestinal barrier function,and modulating epigenetic modifications such as SCD gene methylation.Postoperatively,FFA and TNF-αform a bidirectional promoting feedback loop.LSG effectively breaks this vicious cycle of mutual promotion between the two under obese conditions by reducing FFA levels and inhibiting TNF-αexpression.Lower FFA levels alleviate inflammatory signal activation,while reduced TNF-αinhibits lipolysis,collectively promoting the restoration of insulin sensitivity.A thorough understanding of these mechanisms provides a theoretical basis for optimizing surgical strategies and developing targeted therapies.展开更多
基金Supported by National Natural Science Foundation of China(12101482)Postdoctoral Science Foundation of China(2022M722604)+2 种基金General Project of Science and Technology of Shaanxi Province(2023-YBSF-372)The Natural Science Foundation of Shaan Xi Province(2023-JCQN-0016)Shannxi Mathmatical Basic Science Research Project(23JSQ042)。
文摘In order to better describe the phenomenon of biological invasion,this paper introduces a free boundary model of biological invasion.Firstly,the right free boundary is added to the equation with logistic terms.Secondly,the existence and uniqueness of local solutions are proved by the Sobolev embedding theorem and the comparison principle.Finally,according to the relevant research data and contents of red fire ants,the diffusion area and nest number of red fire ants were simulated without external disturbance.This paper mainly simulates the early diffusion process of red fire ants.In the early diffusion stage,red fire ants grow slowly and then spread over a large area after reaching a certain number.
基金Project supported by the National Natural Science Foundation of China(52104354)the National Natural Science Foundation of China(51674036)+1 种基金Joint Fund for Nuclear Technology Innovation Sponsored by the National Natural Science Foundation of Chinathe China National Nuclear Corporation(U2067201)。
文摘Comprehensive utilization of phosphogypsum(PG)has attracted much attention,especially for the recovery of rare earth elements(REEs)and gypsum due to the issues of stockpile,environmental pollution,and waste of associated resources.Traditional utilization methods suffered the issues of low REEs leaching efficiency,huge amount of CaSO_(4)saturated wastewater and high recovery cost.To solve these issues,this study investigated the occurrence of REEs in PG and the leaching of REEs.The results show that REEs in PG are in the forms of(1)REEs mineral inclusions,(2)REEs isomorphous substitution of Ca^(2+)in gypsum lattice,(3)dispersed soluble REEs salts.Acid leaching results demonstrate that(1)the dissolution of gypsum matrix is the control factor of REEs leaching;(2)H_(2)SO_(4)is a promising leachant considering the recycle of leachate;(3)the gypsum matrix suffers a recrystallization during the acid leaching and releases the soluble REEs from PG to aqueous solution.For the recovery of the undissolved REEs mineral inclusions,wet sieving concentrated 37.1 wt%of the REEs in a 10.7 wt%mass,increasing REEs content from 309 to 1071 ppm.Finally,a green process combining gravity separation and hydrometallurgy is proposed.This process owns the merits of wastewater free,considerable REEs recovery(about 10%increase compared with traditional processes),excellent gypsum purification(>95 wt%CaSO_(4)·2H_(2)O,with<0.06 wt%of soluble P_(2)O_(5) and<0.015 wt%of soluble F)and reagent saving(about 2/3less reagent consumption than non-cyclical leaching).
基金financially supported by the Natural Science Foundation of Zhejiang Province, China (Grant No. LQ22F040001)China Postdoctoral Science Foundation (Grant No. 2022M723281)Science and Technology Planning Project of Shaoxing City (Grant No. 2023B41006)。
文摘Owing to their low toxicity and remarkable stability, perovskites based on antimony and bismuth have garnered significant interest in recent years. However, A_(3)B_(2)X_(9) perovskite materials derived from antimony and bismuth face several challenges, including excessively wide band gaps, elevated defect densities, and suboptimal film quality, all of which hinder advancements in device efficiency. While extensive studies have been undertaken to investigate the effects of modulating the A-site and X-site elements in lead-free A_(3)B_(2)X_(9) perovskites, there remains a notable scarcity of reports addressing the impact of modifications to the B-site element. In this study, we investigated the alloying of antimony and bismuth within the 2D Cs_(3)B_(2)I_(6)Br_(3) perovskite. By systematically varying the ratios of two elements, we found that the incorporation of both antimony and bismuth at the B-site significantly enhances the quality of the perovskite films. Our findings indicate that a 1 : 1 ratio of antimony to bismuth produces the densest films, the highest photoluminescence intensity, and superior photovoltaic performance. Ultimately,the devices fabricated using this optimal ratio achieved an open-circuit voltage(VOC) of 1.01 V and a power conversion efficiency(PCE) of 0.645%.
基金Supported by the Grant-in-Aid for Scientific Research(C)by the Japan Society for the Promotion of Science(20K03615)。
文摘Let G be a group.The family of all sets which are closed in every Hausdorf group topology of G form the family of closed sets of a T_(1) topology M_(G) on G called the Markov topology.Similarly,the family of all algebraic subsets of G forms a family of closed sets for another T_(1)topology Z_(G) on G called the Zarski topology.A subgroup H of G is said to be Markov(resp.Zarski)embedded if the equality M_(G|H)=M_(H)(resp.Z_(G|H)=Z_(H))holds.I's proved that an abirary subgroup of a free group is both Zariski and Markov embedded in it.
基金result of the“Research on ESG Supply Chain Governance and Labor Rights Protection”(Project Number SUFE-ESG-20250315)a general subject project of the Fullgoal Institute for ESG Research,SUFE in 2025.
文摘Labor provisions have become a fundamental trade rule in regional and bilateral trade agreements.Although China’s legislation on pilot Free Trade Zones includes content related to labor protection,it primarily aligns with labor indicators in“Doing Business”,the assessment of business situations issued by the World Bank.It differs from the labor rights protection focus emphasized in trade agreements.The latest strategic documents issued by the State Council of China have addressed this issue to fully achieve the goal of aligning Free Trade Zones with high-standard trade agreements.Building on the development of Free Trade Zone legislation and domestic labor law governance,China should proactively explore a tailored approach to labor provisions in Free Trade Agreements.In this approach,it should explicitly define the“baseline”and“ceiling”for labor provisions during negotiations and,within this framework,establish benchmarks for labor rights protection,enforcement mechanisms,and cross-border regulatory mechanisms suited to the specific conditions of the agreement parties.
基金the National Natural Science Foundation of China under grant No.12372173the Natural Science Foundation of Shanghai under grant No.23ZR1468600.
文摘Silicon,a leading candidate for electrode material for lithium-ion batteries,has garnered significant attention.During the initial lithiation process,the alloying reaction between silicon and lithium transforms the pristine silicon microstructure from crystalline to amorphous,resulting in plastic deformation of the amorphous phase.This study proposes the free volume theory to develop a fully coupled Cahn-Hilliard phase-field model that integrates viscoplastic deformation,free volume evolution,and diffusion.This model investigates the chemophysical phenomenon of self-limiting behavior occurring during the initial lithiation of silicon anodes.Unlike most existing models,the proposed model considers free volume-dependent diffusion using a physically-based approach.The model’s temporal variation in the lithiated phase thickness aligns well with experimental results,confirming the model’s accuracy.Stress field calculations reveal the coexistence of compressive and tensile stresses within the lithiated phase,which may not cause the limiting effect under the frame of the stress-induced diffusion.Analyses indicate that high effective stress increases free volume,enhancing lithium diffusion and augmenting the diffusion coefficient.Reducing the diffusion coefficient in the lithiated phase due to free volume evolution is the primary cause of self-limiting lithiation.
基金Exploration and Practice of the Application of Blockchain Technology in the Cultivation of Composite Talents in the Context of the Free Trade Port(Project No.:HKJG2023-18)。
文摘As an important strategic fulcrum for China’s new round of opening-up,the Hainan Free Trade Port provides broad space for achieving high-quality development with its unique policy advantages and financial resources.In this context,integrating blockchain technology into the construction of the free trade port can not only help enhance the innovation and competitiveness of the talent cultivation system but also promote the coordinated development of the real economy and the industrial system.Based on the core characteristics of blockchain technology,such as“decentralization,traceability,and high credibility”,this paper focuses on the common problems in the cultivation of composite talents in current vocational colleges,including an imperfect school-enterprise cooperation guarantee mechanism,a lack of teaching resources,weak teaching staff,and insufficient practical conditions.It proposes a new idea of introducing blockchain technology into the vocational education system.Through the research on the cultivation model of composite-skilled talents in vocational colleges in the context of“blockchain+”,this paper aims to promote the in-depth integration of vocational education in vertical and horizontal aspects,and further promote the systematic,standardized,and high-quality development of composite talent cultivation.
基金the financial support from the Natural Science Foundation of Jiangsu Province(Grant Nos.BE2022071 and BK20192001)the National Natural Science Foundation of China(Grant Nos.12074194,62471248,12104240,and 62101285)the Postgraduate Research&Practice Innovation Program of Jiangsu Province(Grant No.KYCX220954)。
文摘Quantum digital signature(QDS)can guarantee the information-theoretical security of a signature with the fundamental laws of quantum physics.However,most current QDS protocols do not take source security into account,leading to an overestimation of the signature rate.In this paper,we propose to utilize Hong–Ou–Mandel interference to characterize the upper bound of the source imperfections,and further to quantify information leakage from potential side-channels.Additionally,we combine decoy-state methods and finite-size analysis in analyzing the signature rate.Simulation results demonstrate the performance and feasibility of our approach.Our current work can improve the practical security of QDS systems,thereby promoting their further networked applications.
文摘Too much screen time is bad for your brain and body.It can also waste your time.So,try to spend less time on scree ns.Changing habits is not easy,but you can do it.Use an app to track your time on your smartphone.Do you waste a lot of time on some ofyour phone apps?Take them off or set time limits for them.Less screen time means more free time for other things.Go hiking,visit a museum or try a new hobby.Use your phone less and appreciate life more.
文摘The high temporal and spatial coherence of free electron lasers(FELs)reduces the uniformity of the illumination field,leading to scattering effects that blur the edges of patterns,resulting in diminished accuracy and clarity.Traditional imaging models regard the light source as fully incoherent,making it difficult to assess the impact of partially coherent light fields on imaging.If FELs are used in imaging systems,their coherence must be considered.To address this issue,this study explores the relationship between coherence,imaging quality and speckle contrast through a simulation method based on random phases.The method divides the light beam into temporal and spatial coherence cells,analyzes their interactions,and simulates imaging results under different coherence conditions.Additionally,speckle patterns for various illumination modes are calculated to evaluate their effects on speckle contrast and illumination uniformity.The results indicate that under different illumination modes,illumination uniformity decreases as coherence increases,while speckle contrast increases with higher coherence.In terms of imaging quality,higher coherence leads to an increase in both line edge roughness(LER)and line width roughness(LWR),thereby reducing the imaging quality.Additionally,the narrower the line width,the greater the impact of coherence on the imaging quality,resulting in poorer imaging performance.
基金General Scientific Research Project of Hainan Vocational University of Science and Technology-—Exploration of the Impact of Financial Reform on Enterprises in Hainan Free Trade Port(HKKY2024-13)。
文摘With the development of global economic integration,building a world-class facilitating business environment has become an urgent need for Hainan Free Trade Port.To solve the existing problems in financial policies,legal supervision,and other aspects,this paper takes Hainan Free Trade Port as an example to analyze and study its institutional integration strategy for creating a world-class facilitating business environment.The specific integration strategies are summarized to promote the internationalization and facilitation of the business environment of Hainan Free Trade Port and promote the high development of the local economy.
基金supported by the National Natural Science Foundation of China(No.12175077).
文摘A thermionic gun is endowed with a long bunch tail,which presents challenges for the compact terahertz free electron laser(FEL)facility at the Huazhong University of Science and Technology.Owing to a large energy spread,the tail particles do not contribute to the radiation.In the original design,an x-direction slit is used in the dispersive section of the transport line to remove the tail particles.This paper presents an improved scheme to remove the tail by introducing an RF beam chopper system at the exit of the electron gun,to prevent a significant number of tail particles from entering the linac.The facility remains compact while effectively removing the tail of the bunch.The parameters of the beam chopper system are designed.Bunch parameters and radiation performance are analyzed via a start-to-end simulation.The findings indicate that 43%of the particles can pass through the beam chopper system for subsequent acceleration and transport,which saves the RF power,reduces beam loss in the linac,reduces background noise,and suppresses the sideband instability.Simultaneously,the beam chopper system causes an increase in beam emittance,energy spread,and an offset in the center of the bunch.These effects can be mitigated by a solenoid,linac,and steering coils.The simulation results for the FEL show that the micro-pulse energy is greater than 1.1μJ in the frequency range of 2.8-9.7 THz,and the maximum micro-pulse energy is 1.28μJ.
基金supported by Ministry of Science and Technology of China(2022YFA1303100)the National Natural Science Foundation of China(No.32090040)。
文摘Nucleotide binding domain,leucine-rich repeat,and pyrin domain-containing 3(NLRP3)is an NLR-protein family member that can be activated by diverse exogenous and endogenous stimuli but without direct binding of any of these pathogen ligands.Biological studies show that inactive NLRP3 is usually in an as-sembly state and its activation requires a kinase protein,NEK7.However,our re-cent computational studies as well as other biological investigations have demonstrated that NEK7 does not play a significant role in the activation of NLRP3 assembly and activation.In-stead,biological studies suggest that NEK7 is essential in the dissociation of inactive NLRP3 assemblies.Despite extensive research,the dissociation mechanism of the inactive NLRP3 as-sembly remains largely elusive.In this work,an improved MM-PBSA method is applied to the protein-protein binding free energies in the inactive NLRP3 decamer.Combined with the po-tential mean force(PMF)computation for the 0°→5°conformational change,the standard free-energy change,ΔG^(0)is calculated for NEK7-driven association of the inactive NLRP3 de-camer.Our calculations show that in the absence of NEK7,the dissociation of the inactive NLRP3 decamer is an energetically unfavorable process(ΔG^(0)=99.69 kcal/mol),whereas upon NEK7 binding,the overall standard free energy differenceΔG^(0)=-24.21 kcal/mol is obtained for the inactive NLRP3 decamer dissociation.The free-energy difference calcula-tions in this work also disclose an energetically optimized dissociation pathway,along which the inactive NLRP3 decamer is disunited by a one-by-one dissociation mechanism.
基金supported by the Fundamental Research Program(grant no.:JYZZ228)the Clinical Research Booster Program(grant no.JYLJ202311)of the Shanghai Ninth Peoples’Hospital of Shanghai Jiao Tong University School of Medicine.
文摘Background:Free flap transplantation has emerged as a prevalent technique in reconstructive surgery for patients with oral cancer.Postoperative monitoring of flap perfusion is critical for flap survival,necessitating early detection and timely intervention.Developing a monitoring approach that is highly sensitive,specific,noninvasive,continuous,and cost-effective is crucial for accurately assessing flap perfusion and informing clinical decisions.Methods:From April 2024 to December 2024,20 patients with oral tumors requiring flap transplantation were enrolled at the Ninth People’s Hospital affiliated to Shanghai Jiao Tong University School of Medicine.Continuous monitoring of various free flaps was performed utilizing a transcutaneous blood gas analyzer,both before and after surgery.This approach allowed for real-time measurement of transcutaneous partial pressure of oxygen(TcPO_(2))and transcutaneous partial pressure of carbon dioxide(TcPCO_(2)),facilitating the evaluation of perfusion dynamics across various free flap types.Results:After free flap transplantation,a reduction in blood supply resulted in a rapid decline in TcPO_(2)(to below 10 mmHg),accompanied by a gradual increase in TcPCO_(2),peaking at 135 mmHg.Following vascular anastomosis and blood flow restoration,TcPO_(2)and TcPCO_(2)exhibited opposite trends.Statistical analysis revealed no significant differences in TcPO_(2)and TcPCO_(2)measurements among the various flap types(P<0.05),indicating a consistent pattern of change across all flaps.Conclusion:The transcutaneous blood gas analyzer proves to be a reliable method for monitoring free flap perfusion.Dynamic changes in TcPO_(2)and TcPCO_(2)effectively reflect blood supply status,enabling early detection of vascular compromise and potentially enhancing flap preservation outcomes.
基金funded by the National College Students Innovation and Entrepreneurship Training Program(202411646031)the Zhejiang Xinmiao Talents Program(2024R405A052)the SRIP Research Program of Ningbo University(2025SRIP1707).
文摘The dynamic behavior of high-speed craft navigating through variable sea states plays a pivotal role in ensuring maritime safety.However,many existing simulation approaches rely on linear or overly simplified representations of the marine environment,thereby limiting the fidelity of motion predictions.This study explores the motion characteristics of a 4.5-t high-speed vessel by conducting fully coupled numerical simulations using the STAR-CCM+software.The analysis considers both calm and varying sea conditions,incorporating fluctuations in wave height,wavelength,and wind speed to reflect more realistic operating scenarios.Simulation results reveal that the vessel’s hydrodynamic response is highly sensitive to changes in sea state.As conditions deteriorate,the free surface becomes increasingly complex,with higher wave amplitudes and more pronounced interactions between the waves generated by the vessel and those imposed by the external environment.These effects lead to significant increases in roll,pitch,heave,and sway motions,thereby imposing greater demands on the vessel’s dynamic stability and operational safety.Furthermore,both hydrodynamic resistance and propulsive thrust exhibit notable dependence on sea state and vessel speed.Total resistance generally increases with rougher sea conditions,while thrust tends to rise with increasing forward speed.Under calm or mildly disturbed waters,a Froude number(Fr)of 0.5 appears to offer an optimal balance for initiating and controlling primary motions such as roll,pitch,heave,and sway.Conversely,in more challenging conditions-such as those represented by a Sea State 3-effective motion control is better achieved at a higher Froude number of approximately 1.0.
基金Supported by the National Key R&D Program of China(2022YFB3303501)the National Natural Science Foundation of China(Project Nos.52176041 and 12102308)the Fundamental Research Funds for the Central Universities(Project Nos.2042023kf0208 and 2042023kf0159).
文摘Verification and validation(V&V)is a helpful tool for evaluating simulation errors,but its application in unsteady cavitating flow remains a challenging issue due to the difficulty in meeting the requirement of an asymptotic range.Hence,a new V&V approach for large eddy simulation(LES)is proposed.This approach offers a viable solution for the error estimation of simulation data that are unable to satisfy the asymptotic range.The simulation errors of cavitating flow around a projectile near the free surface are assessed using the new V&V method.The evident error values are primarily dispersed around the cavity region and free surface.The increasingly intense cavitating flow increases the error magnitudes.In addition,the modeling error magnitudes of the Dynamic Smagorinsky-Lilly model are substantially smaller than that of the Smagorinsky-Lilly model.The present V&V method can capture the decrease in the modeling errors due to model enhancements,further exhibiting its applicability in cavitating flow simulations.Moreover,the monitoring points where the simulation data are beyond the asymptotic range are primarily dispersed near the cavity region,and the number of such points grows as the cavitating flow intensifies.The simulation outcomes also suggest that the re-entrant jet and shedding cavity collapse are the chief sources of vorticity motions,which remarkably affect the simulation accuracy.The results of this study provide a valuable reference for V&V research.
基金supported by the NSFC(11571177)the National Key Research and Development Program of China(2020YFA0713803).
文摘In this paper,we consider the plasma-vacuum interface problem in a cylindrical tube region impressed by a special background magnetic field.The interior region is occupied with plasma,which is governed by the incompressible inviscid and resistive MHD system without damping term.The exterior vacuum region is governed by the so-called the“pre-Maxwell equations”.And on the free interface,additionally,the effect of surface tension is taken into account.The original region can be transformed into a horizontally periodic slab through the cylindrical coordinate transformation,which will be impressed by a uniform nonhorizontal magnetic field.Appending with the appropriate physical boundary conditions,the global well-posedness of the problem is established by the energy method.
基金supported by the National Natural Science Foundation of China(No.12372153)the Funding by Guangdong Basic and Applied Basic Research Foundation(No.2023A1515012366)。
文摘In this study,the free vibration of a piezoelectric semiconductor(PS)composite structure composed of a PS layer,a fractional viscoelastic layer,and an elastic substrate with simply-supported boundary conditions is investigated.The fractional derivative Zener model is used to establish the constitutive relation of the viscoelastic layer.The first-order shear deformation theory and Hamilton's principle are used to derive the motion equations of the present problem.The frequency parameter is numerically resolved with the Newton-Raphson method through the eigenvalue equation.The effects of either geometric parameters,carrier density,and electric voltage applied on the surface of the composite structure or the fractional order of the Zener model on both the natural frequency and loss factor are discussed,and some interesting conclusions are drawn.This work will be helpful for designing and manufacturing PS materials and structures.
文摘The construction project of a non-super high-rise public building in Guangzhou’s Nansha Free Trade Zone faces unique challenges.The project established a full-cycle technical management system,encompassing technical management across various sectors and BIM collaboration.Simultaneously,it introduced advanced technical management such as deep foundation pits and core tube construction,along with a risk management system and special weather response strategies.Through these measures,the project achieved numerous significant results,forming a unique management paradigm that offers valuable insights for similar engineering projects.
基金Medical Science and Technology Disciplinary Reserve Talent Program under the Kunming Municipal Health Science and Technology Talent Cultivation Project(Project No.:2024-SW(Reserve)-45)Health Research Project of the Kunming Municipal Health Commission(Project No.:2023-03-06-012)。
文摘Laparoscopic sleeve gastrectomy(LSG),as an effective treatment for morbid obesity and its metabolic complications,exerts its therapeutic effects by significantly reducing body weight and improving metabolic disorders.Its core mechanisms involve multi-level regulation of free fatty acid(FFA)metabolism and chronic low-grade inflammatory states(represented by tumor necrosis factor-alpha,TNF-α).This paper systematically reviews the direct impact of LSG on FFA dynamics including lipolysis,tissue uptake,and oxidation,as well as the molecular pathways through which it indirectly regulates TNF-αby reducing adipose tissue inflammation,improving intestinal barrier function,and modulating epigenetic modifications such as SCD gene methylation.Postoperatively,FFA and TNF-αform a bidirectional promoting feedback loop.LSG effectively breaks this vicious cycle of mutual promotion between the two under obese conditions by reducing FFA levels and inhibiting TNF-αexpression.Lower FFA levels alleviate inflammatory signal activation,while reduced TNF-αinhibits lipolysis,collectively promoting the restoration of insulin sensitivity.A thorough understanding of these mechanisms provides a theoretical basis for optimizing surgical strategies and developing targeted therapies.
