The multi-objective particle swarm optimization algorithm(MOPSO)is widely used to solve multi-objective optimization problems.In the article,amulti-objective particle swarm optimization algorithmbased on decomposition...The multi-objective particle swarm optimization algorithm(MOPSO)is widely used to solve multi-objective optimization problems.In the article,amulti-objective particle swarm optimization algorithmbased on decomposition and multi-selection strategy is proposed to improve the search efficiency.First,two update strategies based on decomposition are used to update the evolving population and external archive,respectively.Second,a multiselection strategy is designed.The first strategy is for the subspace without a non-dominated solution.Among the neighbor particles,the particle with the smallest penalty-based boundary intersection value is selected as the global optimal solution and the particle far away fromthe search particle and the global optimal solution is selected as the personal optimal solution to enhance global search.The second strategy is for the subspace with a non-dominated solution.In the neighbor particles,two particles are randomly selected,one as the global optimal solution and the other as the personal optimal solution,to enhance local search.The third strategy is for Pareto optimal front(PF)discontinuity,which is identified by the cumulative number of iterations of the subspace without non-dominated solutions.In the subsequent iteration,a new probability distribution is used to select from the remaining subspaces to search.Third,an adaptive inertia weight update strategy based on the dominated degree is designed to further improve the search efficiency.Finally,the proposed algorithmis compared with fivemulti-objective particle swarm optimization algorithms and five multi-objective evolutionary algorithms on 22 test problems.The results show that the proposed algorithm has better performance.展开更多
Cp_(2)TiCl_(2) as a Lewis acid precursor and nicotinic acid as a ligand have been used synergistically for the one-pot synthesis of 2-(N-substituted amino)-1,4-naphthoquinones.This method establishes a general strateg...Cp_(2)TiCl_(2) as a Lewis acid precursor and nicotinic acid as a ligand have been used synergistically for the one-pot synthesis of 2-(N-substituted amino)-1,4-naphthoquinones.This method establishes a general strategy for the functionalization and conversion of C-H bonds of 1,4-naphthoquinones into C-N bonds,providing an effective route to synthesize 2-(N-substituted amino)-1,4-naphthoquinone with high yield under mild conditions.Additionally,the synergistic catalytic mechanism was investigated by 1H NMR titration experiments and LC-MS analysis,with experimental results sufficiently and consistently supporting the proposed mechanism of the catalytic cycle.展开更多
Repeated wet swelling and dry shrinkage of soil leads to the gradual occurrence of cracks and the formation of a complex fracture network.In order to study the development characteristics and quantitative analysis of ...Repeated wet swelling and dry shrinkage of soil leads to the gradual occurrence of cracks and the formation of a complex fracture network.In order to study the development characteristics and quantitative analysis of cracks in root-soil complex in different growth periods under dry-wet cycles,the alfalfa root-loess complex was in-vestigated during different growth periods under different dry-wet cycles,and a dry-wet cycle experiment was conducted.The crack rate,relative area,average width,total length,and the cracks fractal dimension in the root-soil complex were extracted;the crack development characteristics of plain soil were analyzed under the PG-DwC(dry-wet cycle caused by plant water management during plant growth period),as well as the crack development characteristics of root-soil complex under PG-DWC and EC-DWC(the dry-wet cycles caused by extreme natural conditions such as continuous rain);the effects of plant roots and dry-wet cycles on soil cracks were discussed.The results showed that the average crack width,crack rate,relative crack area,and total crack length of the alfalfa root-loess complex were higher than those of the plain soil during PG-DWC.The result indicated that compared with plain soil during PG-DWC,the presence of plant roots in alfalfa root-soil complex in the same growth period promoted the cracks development to some extent.The alfalfa root-soil complex crack parameters during different growth periods were relatively stable during PG-DWC(O dry-wet cycle).During EC-DWC(1,3,and 5 dry-wet cycles),the alfalfa root-loess complex crack parameters increased with the number of dry-wet cycles during different growth periods.Unlike PG-DWC,the EC-DWC accelerated crack development,and the degree of crack development increased with the number of dry-wet cycles.The existence of plant roots promoted crack development and expansion in the root-soil complex to a certain extent,and the dry-wet cycle certainly promoted crack development and expansion in the root-soil complex.This result contradicts the im-provement in the root-soil complex's macro-mechanical properties during plant growth,due to differences in the mechanical properties of roots and soil.The research results will provide reference for the root soil complex crack development law and the design of slope protection by vegetation.展开更多
Defect engineering is a commonly methodology used to enhance the thermoelectric performance of thermoelectric PbTe by improving its electronic transport properties.At the nanoscale,defects can induce quantum tunneling...Defect engineering is a commonly methodology used to enhance the thermoelectric performance of thermoelectric PbTe by improving its electronic transport properties.At the nanoscale,defects can induce quantum tunneling effects that significantly impact the electrical properties of materials.To understand the specific mechanisms underlying the quantum transport properties of PbTe,we employ the non-equilibrium Green's function(NEGF)method to investigate the effects of intrinsic defects(point defects and grain boundaries)on the electronic transport properties of PbTe-based nanodevices from a quantum mechanical perspective.Our results show that the Pb vacancy(VPb)has the highest conduction.The conduction depends on the defect type,chemical potential and bias voltage.The presence of intrinsic point defects introduces impurity levels,facilitating the electron tunneling and leading to an increase in the transmission coefficient,thereby enhancing the electronic transport properties.For PbTe containing grain boundaries,these boundaries suppress the electronic transport properties.The Te occupied twin boundary(Te-TB)exerts a stronger inhibitory effect than the Pb occupied twin boundary(Pb-TB).Nevertheless,the combined effect between twin boundaries and point defects can enhance the electrical properties.Therefore,in order to obtain highly conductive of PbTe materials,a Te-rich synthesis environment should be used to promote the effective formation of Pb vacancy.Our work offers a comprehensive understanding of the impact of defects on electron scattering in thermoelectric materials.展开更多
The published article titled“Comparison of Structural Probabilistic and Non-Probabilistic Reliability Computational Methods under Big Data Condition”[1]has been retracted from Structural Durability&Health Monito...The published article titled“Comparison of Structural Probabilistic and Non-Probabilistic Reliability Computational Methods under Big Data Condition”[1]has been retracted from Structural Durability&Health Monitoring(SDHM),Vol.16,No.2,2022,pp.129–143.展开更多
The sulfur-fumigation process not only induces the chemical transformation of Lycium barbarum(Lb,a widely used traditional Chinese medicine)but also severely influences human health.Given the existing challenges like ...The sulfur-fumigation process not only induces the chemical transformation of Lycium barbarum(Lb,a widely used traditional Chinese medicine)but also severely influences human health.Given the existing challenges like the complex and time-consuming operation,as well as the high technical demands of the current detection methods for sulfur-fumed Lycium barbarum(SF-Lb),this paper employs a simple chemiresistor to carry out discrimination research between Lb and SF-Lb which have significant differences in volatolomics.The sensor is constructed by a conductive metal-organic framework(cMOF)thin film,Cu_(3)(HHTP)_(2),due to its abundant active sites,excellent electron transfer performance as well as the capacity to detect specific groups of volatile organic compounds(VOCs).Consequently,the response values of Cu_(3)(HHTP)_(2)-based sensor to 0.5 g SF-Lb(151.74%)are significantly higher than those to normal Lb(80.07%),identifying SF-Lb simply and rapidly with an accuracy of~100%.Our work investigates volatolomics of SF-Lb and establishes a new rapid discrimination method for sulfur-fumed traditional Chinese herbs.展开更多
The cell membrane,a fluid interface composed of self-assembled phospholipid molecules,is a vital component of biological systems that maintains cellular stability and prevents the invasion of foreign toxins.Due to its...The cell membrane,a fluid interface composed of self-assembled phospholipid molecules,is a vital component of biological systems that maintains cellular stability and prevents the invasion of foreign toxins.Due to its inherent fluidity,the cell membrane can undergo bending,shearing,and stretching,making membrane deformation crucial in processes like cell adhesion,migration,phagocytosis,and signal transduction.Within the plasma membrane are highly ordered dynamic structures formed by lipid molecules,known as“lipid rafts,”whose dynamic dissociation and reorganization are prerequisites for membrane deformation.Fluorescent probes have emerged as vital tools for studying these dynamic processes,offering a non-destructive,in situ,and real-time imaging method.By strategically designing these probes,researchers can image not only the microdomains of cell membranes but also explore more complex processes such as membrane fusion and fission.This review systematically summarizes the latest advancements in the application of fluorescent probes for cell membrane imaging.It also discusses the current challenges and provides insights into future research directions.We hope this review inspires further studies on the dynamic processes of complex cell membranes using fluorescent probes,ultimately advancing our understanding of the mechanisms underlying membrane dissociation,reorganization,fusion,and separation,and fostering research and therapeutic development for membrane-associated diseases.展开更多
Fluorescence imaging techniques represent essential tools in in vitro,preclinical,and clinical studies.In this study,an improved one-step hydrothermal method to synthesize citric acid(CA)modifiedα-NaYbF_(4):2%Er^(3+)...Fluorescence imaging techniques represent essential tools in in vitro,preclinical,and clinical studies.In this study,an improved one-step hydrothermal method to synthesize citric acid(CA)modifiedα-NaYbF_(4):2%Er^(3+)nanocrystals was proposed.The introduction of various doping ions into NaYbF_(4):2%Er^(3+)and the different valence states of the same ions affect both the crystal size and upconversion luminesce nce.There fore,we investigated the upconversion luminesce nce enha ncement of NaYbF_(4):2%Er^(3+)by ion doping and find that the upconversion luminescence intensity of the upconversion nanoparticles(UCNPs)co-doped with 5 mol%Fe^(2+)ions shows the greatest enhancement,especially for red emission at654 nm.Furthermore,HeLa cells incubated with UCNPs allow for imaging with strong red upconversion emission detectio n.Confocal laser scanning microscope(CLSM)fluorescent images of HeLa cells indicate that NaYbF_(4):2%Er/5%Fe^(2+)leads to a clear outline and improves visualization of the cell morphology.In addition,the CA coated NaYbF_(4):2%Er^(3+)/5%Fe^(2+)nanoparticles and NaYbF_(4):2%Er^(3+)/5%Fe^(2+)show low cytotoxicity in HeLa cells.Organ imaging reveals the efficiency of these UCNPs to analyze the lungs,liver,and spleen.Together,these results indicate that the Cit-NaYbF_(4):2%Er^(3+)/5%Fe^(2+)UCNPs are efficient nanoprobes for fluorescence molecular to mography.展开更多
In this article,structural probabilistic and non-probabilistic reliability have been evaluated and compared under big data condition.Firstly,the big data is collected via structural monitoring and analysis.Big data is...In this article,structural probabilistic and non-probabilistic reliability have been evaluated and compared under big data condition.Firstly,the big data is collected via structural monitoring and analysis.Big data is classified into different types according to the regularities of the distribution of data.The different stresses which have been subjected by the structure are used in this paper.Secondly,the structural interval reliability and probabilistic pre-diction models are established by using the stress-strength interference theory under big data of random loads after the stresses and structural strength are comprehensively considered.Structural reliability is computed by using various stress types,and the minimum reliability is determined as structural reliability.Finally,the advan-tage and disadvantage of the interval reliability method and probability reliability method are shown by using three examples.It has been shown that the proposed methods are feasible and effective.展开更多
Triaxial compression tests were conducted on the alfalfa root-loess complex at different growthperiods obtained through artificial planting.The research focused on analyzing the time variation law of the shear strengt...Triaxial compression tests were conducted on the alfalfa root-loess complex at different growthperiods obtained through artificial planting.The research focused on analyzing the time variation law of the shear strength index and deformation index of the alfalfa root-loess complex under dry-wet cycles.Additionally,the time effect of the shear strength index of the alfalfa root-loess complex under dry-wet cycles was analyzed and its prediction model was proposed.The results show that the PG-DWC(dry-wet cycle caused by plant water management during plant growth period)causes the peak strength of plain soil to change in a"V"shape with the increase of growth period,and the peak strength of alfalfa root-loess complex is higher than that of plain soil at the same growth period.The deterioration of the peak strength of alfalfa root-loess complex in the same growth period is aggravated with the increase of drying and wetting cycles.Compared with the 0 days growth period,the effective cohesion of alfalfa root-loess complex under different dry-wet cycles maximum increase rate is at the 180 days,which are 33.88%,46.05%,30.12%and 216.02%,respectively.When the number of dry-wet cycles is constant,the effective cohesion of the alfalfa root-loess complex overall increases with the growth period.However,it gradually decreases comparedwith the previous growth period,and the minimum increase rate are all at the 180 days.For the same growth period,the effective cohesion of the alfalfa root-loess complex decreases with the increase of the number of dry-wet cycles.This indicates that EC-DWC(the dry-wet cycles caused by extreme natural conditions such as continuous rain)have a detrimental effect on the time effect of the shear strength of the alfalfa root-loess complex.Finally,based on the formula of total deterioration,a prediction model for the shear strength of the alfalfa root-loess complex under dry-wet cycles was proposed,which exhibits high prediction accuracy.The research results provide useful guidance for the understanding of mechanical behavior and structural damage evolution of root-soil composite.展开更多
This paper deals with the problem of limit cycles for the whirling pendulum equation x=y,y=sin x(cosx-r)under piecewise smooth perturbations of polynomials of cos x,sin x and y of degree n with the switching line x=0....This paper deals with the problem of limit cycles for the whirling pendulum equation x=y,y=sin x(cosx-r)under piecewise smooth perturbations of polynomials of cos x,sin x and y of degree n with the switching line x=0.The upper bounds of the number of limit cycles in both the oscillatory and the rotary regions are obtained using the Picard-Fuchs equations,which the generating functions of the associated first order Melnikov functions satisfy.Furthermore,the exact bound of a special case is given using the Chebyshev system.At the end,some numerical simulations are given to illustrate the existence of limit cycles.展开更多
In this paper,the nonlinear potential theory in the Morrey spaces on Euclidean spaces and the Lebesgue spaces on the Carnot group are studied.According to the methods of abstract harmonic analysis in Heisenberg group ...In this paper,the nonlinear potential theory in the Morrey spaces on Euclidean spaces and the Lebesgue spaces on the Carnot group are studied.According to the methods of abstract harmonic analysis in Heisenberg group and abstract potential theory in carnot group,we mainly give some characterizations for Riesz,Bessel and Wolff potentials,and the corresponding capacities in the Morrey spaces on Carnot group.Meanwhile,we also interpret the relation among Riesz and Bessel type capacities and Housdorff content in the Morrey spaces on Carnot group.All these results above generalize the related ones in the Morrey spaces on Euclidean spaces and the Lebesgue spaces on the Carnot group.展开更多
In this paper,a new finite element and finite difference(FE-FD)method has been developed for anisotropic parabolic interface problems with a known moving interface using Cartesian meshes.In the spatial discretization,...In this paper,a new finite element and finite difference(FE-FD)method has been developed for anisotropic parabolic interface problems with a known moving interface using Cartesian meshes.In the spatial discretization,the standard P,FE discretization is applied so that the part of the coefficient matrix is symmetric positive definite,while near the interface,the maximum principle preserving immersed interface discretization is applied.In the time discretization,a modified Crank-Nicolson discretization is employed so that the hybrid FE-FD is stable and second order accurate.Correction terms are needed when the interface crosses grid lines.The moving interface is represented by the zero level set of a Lipschitz continuous function.Numerical experiments presented in this paper confirm second orderconvergence.展开更多
Tellurene, an emerging two-dimensional chain-like semiconductor, stands out for its high switch ratio, carrier mobility and excellent stability in air. Directly contacting the 2D semiconductor materials with metal ele...Tellurene, an emerging two-dimensional chain-like semiconductor, stands out for its high switch ratio, carrier mobility and excellent stability in air. Directly contacting the 2D semiconductor materials with metal electrodes is a feasible doping means to inject carriers. However, Schottky barrier often arises at the metal–semiconductors interface, impeding the transport of carriers. Herein, we investigate the interfacial properties of BL tellurene by contacting with various metals including graphene by using ab initio calculations and quantum transport simulations. Vertical Schottky barriers take place in Ag, Al, Au and Cu electrodes according to the maintenance of the noncontact tellurene layer band structure. Besides, a p-type vertical Schottky contact is formed due to the van der Waals interaction for graphene electrode. As for the lateral direction, p-type Schottky contacts take shape for bulk metal electrodes(hole Schottky barrier heights(SBHs) ranging from 0.19 to 0.35 eV). Strong Fermi level pinning takes place with a pinning factor of 0.02. Notably, a desirable p-type quasi-Ohmic contact is developed for graphene electrode with a hole SBH of 0.08 eV. Our work sheds light on the interfacial properties of BL tellurene based transistors and could guide the experimental selections on electrodes.展开更多
The main object of this present paper is to investigate the problem of majorization of certain class of multivalent meromorphic functions of complex order involving Mittag-Leffler function. Meanwhile, for this subclas...The main object of this present paper is to investigate the problem of majorization of certain class of multivalent meromorphic functions of complex order involving Mittag-Leffler function. Meanwhile, for this subclass the corresponding coefficient estimates and some Fekete-Szegö type inequalities are obtained. Moreover we point out some new or known consequences of our main results.展开更多
In a cloud environment,outsourced graph data is widely used in companies,enterprises,medical institutions,and so on.Data owners and users can save costs and improve efficiency by storing large amounts of graph data on...In a cloud environment,outsourced graph data is widely used in companies,enterprises,medical institutions,and so on.Data owners and users can save costs and improve efficiency by storing large amounts of graph data on cloud servers.Servers on cloud platforms usually have some subjective or objective attacks,which make the outsourced graph data in an insecure state.The issue of privacy data protection has become an important obstacle to data sharing and usage.How to query outsourcing graph data safely and effectively has become the focus of research.Adjacency query is a basic and frequently used operation in graph,and it will effectively promote the query range and query ability if multi-keyword fuzzy search can be supported at the same time.This work proposes to protect the privacy information of outsourcing graph data by encryption,mainly studies the problem of multi-keyword fuzzy adjacency query,and puts forward a solution.In our scheme,we use the Bloom filter and encryption mechanism to build a secure index and query token,and adjacency queries are implemented through indexes and query tokens on the cloud server.Our proposed scheme is proved by formal analysis,and the performance and effectiveness of the scheme are illustrated by experimental analysis.The research results of this work will provide solid theoretical and technical support for the further popularization and application of encrypted graph data processing technology.展开更多
In this paper, the creep resistance of 2D braided SiC/SiC composites was studied under the stress conditions of 120MPa and 140MPa at 1200℃. The creep curve is obtained through the experiment. Through the analysis and...In this paper, the creep resistance of 2D braided SiC/SiC composites was studied under the stress conditions of 120MPa and 140MPa at 1200℃. The creep curve is obtained through the experiment. Through the analysis and calculation of the creep curve, the material has excellent creep resistance in the environment of 1200℃ and 120MPa, and the creep resistance is reduced due to higher stress in the environment of 1200℃ and 140MPa. Through calculation, the average creep rate of the materials under the two stresses is (5±1) × 10-8/s, (1.6±0.6) × 10-7/s respectively, and the creep rate is increased by 3.2 times under 140MPa stress.展开更多
With the continuous progress of modern society, refined supervision belongs to a new management concept, which is integrated into every industry in the society according to its own reasonable and effective advantages....With the continuous progress of modern society, refined supervision belongs to a new management concept, which is integrated into every industry in the society according to its own reasonable and effective advantages. Student work is the main component of the normal management work in colleges and universities. It plays a positive role in guiding students to form correct values and concepts. College students belong to a special group. They master a lot of knowledge and are very agile in thinking. Especially under the influence of social development and diversification, students' ideology has changed to a certain extent. Introducing refined management into school student work is a choice in school teaching reform.展开更多
The dynamics of a unidirectional nonlinear delayed-coupling chaos system is investigated. Based on the local Hopf bifurcation at the zero equilibrium, we prove the global existence of periodic solutions using a global...The dynamics of a unidirectional nonlinear delayed-coupling chaos system is investigated. Based on the local Hopf bifurcation at the zero equilibrium, we prove the global existence of periodic solutions using a global Hopf bifurcation result due to Wu and a Bendixson’s criterion for higher dimensional ordinary differential equations due to Li & Muldowney.展开更多
Although numerous research advances have been made on asynchronous motors,particularly regarding internal parameters and complex control methods,the causes of the complex dynamic characteristics observed during normal...Although numerous research advances have been made on asynchronous motors,particularly regarding internal parameters and complex control methods,the causes of the complex dynamic characteristics observed during normal motor operation have received less attention.To avoid abnormal vibration damage to the motor under normal operating conditions,the fluctuating nonlinear dynamic characteristics of the motor by considering variable voltages,frequencies,and changing workloads from both analytical and numerical perspectives are investigated.Motor stability was evaluated using the Lienard-Chipart stability criterion and the Runge-Kutta method.The results indicate that speed fluctuations occur within a specific range of input voltage and angular frequency,and the amplitude fluctuation region expands when load variation is considered.Furthermore,the Poincare map and Lyapunov exponent are adopted to determine the oscillation distribution and dynamic characteristics in a typical region.Specifically,the chaos phenomenon mostly occurred at the edge of the unstable region with an increase in the load.In contrast,periodic conciliation is mainly concentrated within the unstable region.展开更多
基金supported by National Natural Science Foundations of China(nos.12271326,62102304,61806120,61502290,61672334,61673251)China Postdoctoral Science Foundation(no.2015M582606)+2 种基金Industrial Research Project of Science and Technology in Shaanxi Province(nos.2015GY016,2017JQ6063)Fundamental Research Fund for the Central Universities(no.GK202003071)Natural Science Basic Research Plan in Shaanxi Province of China(no.2022JM-354).
文摘The multi-objective particle swarm optimization algorithm(MOPSO)is widely used to solve multi-objective optimization problems.In the article,amulti-objective particle swarm optimization algorithmbased on decomposition and multi-selection strategy is proposed to improve the search efficiency.First,two update strategies based on decomposition are used to update the evolving population and external archive,respectively.Second,a multiselection strategy is designed.The first strategy is for the subspace without a non-dominated solution.Among the neighbor particles,the particle with the smallest penalty-based boundary intersection value is selected as the global optimal solution and the particle far away fromthe search particle and the global optimal solution is selected as the personal optimal solution to enhance global search.The second strategy is for the subspace with a non-dominated solution.In the neighbor particles,two particles are randomly selected,one as the global optimal solution and the other as the personal optimal solution,to enhance local search.The third strategy is for Pareto optimal front(PF)discontinuity,which is identified by the cumulative number of iterations of the subspace without non-dominated solutions.In the subsequent iteration,a new probability distribution is used to select from the remaining subspaces to search.Third,an adaptive inertia weight update strategy based on the dominated degree is designed to further improve the search efficiency.Finally,the proposed algorithmis compared with fivemulti-objective particle swarm optimization algorithms and five multi-objective evolutionary algorithms on 22 test problems.The results show that the proposed algorithm has better performance.
基金2024 Special Talent Introduction Projects of Key R&D Program of Ningxia Hui Autonomous Region(2024BEH04049)the 2024 Guyuan City Innovation-Driven Achievement Transformation Project(2024BGTYF01-47)2025 Ningxia Natural Science Foundation Program(2025AAC030624).
文摘Cp_(2)TiCl_(2) as a Lewis acid precursor and nicotinic acid as a ligand have been used synergistically for the one-pot synthesis of 2-(N-substituted amino)-1,4-naphthoquinones.This method establishes a general strategy for the functionalization and conversion of C-H bonds of 1,4-naphthoquinones into C-N bonds,providing an effective route to synthesize 2-(N-substituted amino)-1,4-naphthoquinone with high yield under mild conditions.Additionally,the synergistic catalytic mechanism was investigated by 1H NMR titration experiments and LC-MS analysis,with experimental results sufficiently and consistently supporting the proposed mechanism of the catalytic cycle.
基金the Key Research and Development Project of Ningxia Hui Autonomous Region(No.2023BEG02072)for their financial support.
文摘Repeated wet swelling and dry shrinkage of soil leads to the gradual occurrence of cracks and the formation of a complex fracture network.In order to study the development characteristics and quantitative analysis of cracks in root-soil complex in different growth periods under dry-wet cycles,the alfalfa root-loess complex was in-vestigated during different growth periods under different dry-wet cycles,and a dry-wet cycle experiment was conducted.The crack rate,relative area,average width,total length,and the cracks fractal dimension in the root-soil complex were extracted;the crack development characteristics of plain soil were analyzed under the PG-DwC(dry-wet cycle caused by plant water management during plant growth period),as well as the crack development characteristics of root-soil complex under PG-DWC and EC-DWC(the dry-wet cycles caused by extreme natural conditions such as continuous rain);the effects of plant roots and dry-wet cycles on soil cracks were discussed.The results showed that the average crack width,crack rate,relative crack area,and total crack length of the alfalfa root-loess complex were higher than those of the plain soil during PG-DWC.The result indicated that compared with plain soil during PG-DWC,the presence of plant roots in alfalfa root-soil complex in the same growth period promoted the cracks development to some extent.The alfalfa root-soil complex crack parameters during different growth periods were relatively stable during PG-DWC(O dry-wet cycle).During EC-DWC(1,3,and 5 dry-wet cycles),the alfalfa root-loess complex crack parameters increased with the number of dry-wet cycles during different growth periods.Unlike PG-DWC,the EC-DWC accelerated crack development,and the degree of crack development increased with the number of dry-wet cycles.The existence of plant roots promoted crack development and expansion in the root-soil complex to a certain extent,and the dry-wet cycle certainly promoted crack development and expansion in the root-soil complex.This result contradicts the im-provement in the root-soil complex's macro-mechanical properties during plant growth,due to differences in the mechanical properties of roots and soil.The research results will provide reference for the root soil complex crack development law and the design of slope protection by vegetation.
基金financial support from the National Natural Science Foundation of China(No.12474016)the program of“Distinguished Expert of Taishan Scholar”(No.tstp20221124)+4 种基金the National Natural Science Foundation of China(Nos.52172212,12474017)the Shandong Provincial Science Foundation(ZR2021YQ03)the program for“Young Scientists of Taishan Scholars”(No.tsqn202306184)financial support from the National Natural Science Foundation of China(No.12464034)the Natural Science Foundation of Ningxia,China(No.2024AAC05070)。
文摘Defect engineering is a commonly methodology used to enhance the thermoelectric performance of thermoelectric PbTe by improving its electronic transport properties.At the nanoscale,defects can induce quantum tunneling effects that significantly impact the electrical properties of materials.To understand the specific mechanisms underlying the quantum transport properties of PbTe,we employ the non-equilibrium Green's function(NEGF)method to investigate the effects of intrinsic defects(point defects and grain boundaries)on the electronic transport properties of PbTe-based nanodevices from a quantum mechanical perspective.Our results show that the Pb vacancy(VPb)has the highest conduction.The conduction depends on the defect type,chemical potential and bias voltage.The presence of intrinsic point defects introduces impurity levels,facilitating the electron tunneling and leading to an increase in the transmission coefficient,thereby enhancing the electronic transport properties.For PbTe containing grain boundaries,these boundaries suppress the electronic transport properties.The Te occupied twin boundary(Te-TB)exerts a stronger inhibitory effect than the Pb occupied twin boundary(Pb-TB).Nevertheless,the combined effect between twin boundaries and point defects can enhance the electrical properties.Therefore,in order to obtain highly conductive of PbTe materials,a Te-rich synthesis environment should be used to promote the effective formation of Pb vacancy.Our work offers a comprehensive understanding of the impact of defects on electron scattering in thermoelectric materials.
文摘The published article titled“Comparison of Structural Probabilistic and Non-Probabilistic Reliability Computational Methods under Big Data Condition”[1]has been retracted from Structural Durability&Health Monitoring(SDHM),Vol.16,No.2,2022,pp.129–143.
基金supported by the National Natural Science Foundation of China(Nos.22205121,22494633,22401281)CAS President's International Fellowship for Visiting Scientists(No.2024VBC0002)+2 种基金the research fund of State Key Laboratory of Mesoscience and Engineering(Nos.MESO-23-A07,MESO-23-T02,MESO-24-A01)First-class Discipline Construction Project(Chemistry)in Higher Education Institutions of Ningxia(Ningxia Normal University)Engineering Research Center of Liupanshan(No.HGZD22-27).
文摘The sulfur-fumigation process not only induces the chemical transformation of Lycium barbarum(Lb,a widely used traditional Chinese medicine)but also severely influences human health.Given the existing challenges like the complex and time-consuming operation,as well as the high technical demands of the current detection methods for sulfur-fumed Lycium barbarum(SF-Lb),this paper employs a simple chemiresistor to carry out discrimination research between Lb and SF-Lb which have significant differences in volatolomics.The sensor is constructed by a conductive metal-organic framework(cMOF)thin film,Cu_(3)(HHTP)_(2),due to its abundant active sites,excellent electron transfer performance as well as the capacity to detect specific groups of volatile organic compounds(VOCs).Consequently,the response values of Cu_(3)(HHTP)_(2)-based sensor to 0.5 g SF-Lb(151.74%)are significantly higher than those to normal Lb(80.07%),identifying SF-Lb simply and rapidly with an accuracy of~100%.Our work investigates volatolomics of SF-Lb and establishes a new rapid discrimination method for sulfur-fumed traditional Chinese herbs.
基金supported by the National Nature Science Foundation of China(22107028)State Key Laboratory of Fine Chemicals,Dalian University of Technology(KF2307)+4 种基金Central Guidance Fund for Local Science and Technology Development Project(2024FRD05069)Natural Science Foundation of Chongqing(CSTB2023NSCQ-MSX0335)ML.wishes to thank the support of the National Natural Science Foundation of China(22308220)Shenzhen Uni-versity Third-Phase Project of Constructing High-Level University(000001032104)the Research Team Culti-vation Program of Shenzhen University(2023QNT005).
文摘The cell membrane,a fluid interface composed of self-assembled phospholipid molecules,is a vital component of biological systems that maintains cellular stability and prevents the invasion of foreign toxins.Due to its inherent fluidity,the cell membrane can undergo bending,shearing,and stretching,making membrane deformation crucial in processes like cell adhesion,migration,phagocytosis,and signal transduction.Within the plasma membrane are highly ordered dynamic structures formed by lipid molecules,known as“lipid rafts,”whose dynamic dissociation and reorganization are prerequisites for membrane deformation.Fluorescent probes have emerged as vital tools for studying these dynamic processes,offering a non-destructive,in situ,and real-time imaging method.By strategically designing these probes,researchers can image not only the microdomains of cell membranes but also explore more complex processes such as membrane fusion and fission.This review systematically summarizes the latest advancements in the application of fluorescent probes for cell membrane imaging.It also discusses the current challenges and provides insights into future research directions.We hope this review inspires further studies on the dynamic processes of complex cell membranes using fluorescent probes,ultimately advancing our understanding of the mechanisms underlying membrane dissociation,reorganization,fusion,and separation,and fostering research and therapeutic development for membrane-associated diseases.
基金Project supported by the Natural Science Basic Research Program of Shaanxi Province(2021JZ-43)the Key Program for International Science and Technology Cooperation Projects of Shaanxi Province(2018KWZ-08)+2 种基金the National Key Research and Development Program of China(2019YFC1520904)the Scientific Research Plan of Shannxi Provincial Education Department,China(18JK0780)Ningxia Natural Fund(2023AAC03338)。
文摘Fluorescence imaging techniques represent essential tools in in vitro,preclinical,and clinical studies.In this study,an improved one-step hydrothermal method to synthesize citric acid(CA)modifiedα-NaYbF_(4):2%Er^(3+)nanocrystals was proposed.The introduction of various doping ions into NaYbF_(4):2%Er^(3+)and the different valence states of the same ions affect both the crystal size and upconversion luminesce nce.There fore,we investigated the upconversion luminesce nce enha ncement of NaYbF_(4):2%Er^(3+)by ion doping and find that the upconversion luminescence intensity of the upconversion nanoparticles(UCNPs)co-doped with 5 mol%Fe^(2+)ions shows the greatest enhancement,especially for red emission at654 nm.Furthermore,HeLa cells incubated with UCNPs allow for imaging with strong red upconversion emission detectio n.Confocal laser scanning microscope(CLSM)fluorescent images of HeLa cells indicate that NaYbF_(4):2%Er/5%Fe^(2+)leads to a clear outline and improves visualization of the cell morphology.In addition,the CA coated NaYbF_(4):2%Er^(3+)/5%Fe^(2+)nanoparticles and NaYbF_(4):2%Er^(3+)/5%Fe^(2+)show low cytotoxicity in HeLa cells.Organ imaging reveals the efficiency of these UCNPs to analyze the lungs,liver,and spleen.Together,these results indicate that the Cit-NaYbF_(4):2%Er^(3+)/5%Fe^(2+)UCNPs are efficient nanoprobes for fluorescence molecular to mography.
基金The work described in this paper was supported in part by the Foundation from the Science Foundation,Guizhou,China(Qian Kehe[2018]1055)Research Foundation for Talented Scholars in Ningxia Normal University.
文摘In this article,structural probabilistic and non-probabilistic reliability have been evaluated and compared under big data condition.Firstly,the big data is collected via structural monitoring and analysis.Big data is classified into different types according to the regularities of the distribution of data.The different stresses which have been subjected by the structure are used in this paper.Secondly,the structural interval reliability and probabilistic pre-diction models are established by using the stress-strength interference theory under big data of random loads after the stresses and structural strength are comprehensively considered.Structural reliability is computed by using various stress types,and the minimum reliability is determined as structural reliability.Finally,the advan-tage and disadvantage of the interval reliability method and probability reliability method are shown by using three examples.It has been shown that the proposed methods are feasible and effective.
基金received the Key Research and Development Project of Ningxia Hui Autonomous Region(2022BEG03052,2023BEG02072).
文摘Triaxial compression tests were conducted on the alfalfa root-loess complex at different growthperiods obtained through artificial planting.The research focused on analyzing the time variation law of the shear strength index and deformation index of the alfalfa root-loess complex under dry-wet cycles.Additionally,the time effect of the shear strength index of the alfalfa root-loess complex under dry-wet cycles was analyzed and its prediction model was proposed.The results show that the PG-DWC(dry-wet cycle caused by plant water management during plant growth period)causes the peak strength of plain soil to change in a"V"shape with the increase of growth period,and the peak strength of alfalfa root-loess complex is higher than that of plain soil at the same growth period.The deterioration of the peak strength of alfalfa root-loess complex in the same growth period is aggravated with the increase of drying and wetting cycles.Compared with the 0 days growth period,the effective cohesion of alfalfa root-loess complex under different dry-wet cycles maximum increase rate is at the 180 days,which are 33.88%,46.05%,30.12%and 216.02%,respectively.When the number of dry-wet cycles is constant,the effective cohesion of the alfalfa root-loess complex overall increases with the growth period.However,it gradually decreases comparedwith the previous growth period,and the minimum increase rate are all at the 180 days.For the same growth period,the effective cohesion of the alfalfa root-loess complex decreases with the increase of the number of dry-wet cycles.This indicates that EC-DWC(the dry-wet cycles caused by extreme natural conditions such as continuous rain)have a detrimental effect on the time effect of the shear strength of the alfalfa root-loess complex.Finally,based on the formula of total deterioration,a prediction model for the shear strength of the alfalfa root-loess complex under dry-wet cycles was proposed,which exhibits high prediction accuracy.The research results provide useful guidance for the understanding of mechanical behavior and structural damage evolution of root-soil composite.
基金supported by the Natural Science Foundation of Ningxia(2022AAC05044)the National Natural Science Foundation of China(12161069)。
文摘This paper deals with the problem of limit cycles for the whirling pendulum equation x=y,y=sin x(cosx-r)under piecewise smooth perturbations of polynomials of cos x,sin x and y of degree n with the switching line x=0.The upper bounds of the number of limit cycles in both the oscillatory and the rotary regions are obtained using the Picard-Fuchs equations,which the generating functions of the associated first order Melnikov functions satisfy.Furthermore,the exact bound of a special case is given using the Chebyshev system.At the end,some numerical simulations are given to illustrate the existence of limit cycles.
基金Supported by the Natural Science Foundation of Ningxia(Grant No.2023AAC03001)the National Natural Science Foundation of China(Grant No.12261068)。
文摘In this paper,the nonlinear potential theory in the Morrey spaces on Euclidean spaces and the Lebesgue spaces on the Carnot group are studied.According to the methods of abstract harmonic analysis in Heisenberg group and abstract potential theory in carnot group,we mainly give some characterizations for Riesz,Bessel and Wolff potentials,and the corresponding capacities in the Morrey spaces on Carnot group.Meanwhile,we also interpret the relation among Riesz and Bessel type capacities and Housdorff content in the Morrey spaces on Carnot group.All these results above generalize the related ones in the Morrey spaces on Euclidean spaces and the Lebesgue spaces on the Carnot group.
基金partially supported by the National Natural Science Foundation of China(Grant No.12261070)the Ningxia Key Research and Development Project of China(Grant No.2022BSB03048)+2 种基金partially supported by the Simons(Grant No.633724)and by Fundacion Seneca grant 21760/IV/22partially supported by the Spanish national research project PID2019-108336GB-I00by Fundacion Séneca grant 21728/EE/22.Este trabajo es resultado de las estancias(21760/IV/22)y(21728/EE/22)financiadas por la Fundacion Séneca-Agencia de Ciencia y Tecnologia de la Region de Murcia con cargo al Programa Regional de Movilidad,Colaboracion Internacional e Intercambio de Conocimiento"Jimenez de la Espada".(Plan de Actuacion 2022).
文摘In this paper,a new finite element and finite difference(FE-FD)method has been developed for anisotropic parabolic interface problems with a known moving interface using Cartesian meshes.In the spatial discretization,the standard P,FE discretization is applied so that the part of the coefficient matrix is symmetric positive definite,while near the interface,the maximum principle preserving immersed interface discretization is applied.In the time discretization,a modified Crank-Nicolson discretization is employed so that the hybrid FE-FD is stable and second order accurate.Correction terms are needed when the interface crosses grid lines.The moving interface is represented by the zero level set of a Lipschitz continuous function.Numerical experiments presented in this paper confirm second orderconvergence.
基金supported by the National Natural Science Foundation of China(Nos.11674005,11664026,11704406)the National Materials Genome Project of China(No2016YFB0700600)+4 种基金the Key Research and Development Program of Ningxia(No.2018BEE03023)the Natural Science Foundation of Ningxia(No.2018AAC03236)the Higher Schoo Scientific Research Project of Ningxia Department of Education(No.NGY2018-130)the Key Scientific Research Project of Ningxia Normal University(No.NXSFZDA1807)the Youth Talent Support Program of Ningxia,China(2016)
文摘Tellurene, an emerging two-dimensional chain-like semiconductor, stands out for its high switch ratio, carrier mobility and excellent stability in air. Directly contacting the 2D semiconductor materials with metal electrodes is a feasible doping means to inject carriers. However, Schottky barrier often arises at the metal–semiconductors interface, impeding the transport of carriers. Herein, we investigate the interfacial properties of BL tellurene by contacting with various metals including graphene by using ab initio calculations and quantum transport simulations. Vertical Schottky barriers take place in Ag, Al, Au and Cu electrodes according to the maintenance of the noncontact tellurene layer band structure. Besides, a p-type vertical Schottky contact is formed due to the van der Waals interaction for graphene electrode. As for the lateral direction, p-type Schottky contacts take shape for bulk metal electrodes(hole Schottky barrier heights(SBHs) ranging from 0.19 to 0.35 eV). Strong Fermi level pinning takes place with a pinning factor of 0.02. Notably, a desirable p-type quasi-Ohmic contact is developed for graphene electrode with a hole SBH of 0.08 eV. Our work sheds light on the interfacial properties of BL tellurene based transistors and could guide the experimental selections on electrodes.
基金Supported by Natural Science Foundation of Ningxia(Grant No.2020AAC03066)National Natural Science Foundation of China(Grant Nos.42064004 and 11762016).
文摘The main object of this present paper is to investigate the problem of majorization of certain class of multivalent meromorphic functions of complex order involving Mittag-Leffler function. Meanwhile, for this subclass the corresponding coefficient estimates and some Fekete-Szegö type inequalities are obtained. Moreover we point out some new or known consequences of our main results.
基金This research was supported in part by the Nature Science Foundation of China(Nos.62262033,61962029,61762055,62062045 and 62362042)the Jiangxi Provincial Natural Science Foundation of China(Nos.20224BAB202012,20202ACBL202005 and 20202BAB212006)+3 种基金the Science and Technology Research Project of Jiangxi Education Department(Nos.GJJ211815,GJJ2201914 and GJJ201832)the Hubei Natural Science Foundation Innovation and Development Joint Fund Project(No.2022CFD101)Xiangyang High-Tech Key Science and Technology Plan Project(No.2022ABH006848)Hubei Superior and Distinctive Discipline Group of“New Energy Vehicle and Smart Transportation”,the Project of Zhejiang Institute of Mechanical&Electrical Engineering,and the Jiangxi Provincial Social Science Foundation of China(No.23GL52D).
文摘In a cloud environment,outsourced graph data is widely used in companies,enterprises,medical institutions,and so on.Data owners and users can save costs and improve efficiency by storing large amounts of graph data on cloud servers.Servers on cloud platforms usually have some subjective or objective attacks,which make the outsourced graph data in an insecure state.The issue of privacy data protection has become an important obstacle to data sharing and usage.How to query outsourcing graph data safely and effectively has become the focus of research.Adjacency query is a basic and frequently used operation in graph,and it will effectively promote the query range and query ability if multi-keyword fuzzy search can be supported at the same time.This work proposes to protect the privacy information of outsourcing graph data by encryption,mainly studies the problem of multi-keyword fuzzy adjacency query,and puts forward a solution.In our scheme,we use the Bloom filter and encryption mechanism to build a secure index and query token,and adjacency queries are implemented through indexes and query tokens on the cloud server.Our proposed scheme is proved by formal analysis,and the performance and effectiveness of the scheme are illustrated by experimental analysis.The research results of this work will provide solid theoretical and technical support for the further popularization and application of encrypted graph data processing technology.
文摘In this paper, the creep resistance of 2D braided SiC/SiC composites was studied under the stress conditions of 120MPa and 140MPa at 1200℃. The creep curve is obtained through the experiment. Through the analysis and calculation of the creep curve, the material has excellent creep resistance in the environment of 1200℃ and 120MPa, and the creep resistance is reduced due to higher stress in the environment of 1200℃ and 140MPa. Through calculation, the average creep rate of the materials under the two stresses is (5±1) × 10-8/s, (1.6±0.6) × 10-7/s respectively, and the creep rate is increased by 3.2 times under 140MPa stress.
文摘With the continuous progress of modern society, refined supervision belongs to a new management concept, which is integrated into every industry in the society according to its own reasonable and effective advantages. Student work is the main component of the normal management work in colleges and universities. It plays a positive role in guiding students to form correct values and concepts. College students belong to a special group. They master a lot of knowledge and are very agile in thinking. Especially under the influence of social development and diversification, students' ideology has changed to a certain extent. Introducing refined management into school student work is a choice in school teaching reform.
文摘The dynamics of a unidirectional nonlinear delayed-coupling chaos system is investigated. Based on the local Hopf bifurcation at the zero equilibrium, we prove the global existence of periodic solutions using a global Hopf bifurcation result due to Wu and a Bendixson’s criterion for higher dimensional ordinary differential equations due to Li & Muldowney.
基金Supported by the Ningxia Key Research and Development Program(2020BEB4040)Ningxia Fundamental Research Project(2022AAC3335,2023AAC03332)+2 种基金Scientific Research Project of Ningxia Education Department(NYG2024167)Ningxia Natural Science Foundation(2022AAC03333)Guyuan Research and Development Program(2024BGTYF01-48).
文摘Although numerous research advances have been made on asynchronous motors,particularly regarding internal parameters and complex control methods,the causes of the complex dynamic characteristics observed during normal motor operation have received less attention.To avoid abnormal vibration damage to the motor under normal operating conditions,the fluctuating nonlinear dynamic characteristics of the motor by considering variable voltages,frequencies,and changing workloads from both analytical and numerical perspectives are investigated.Motor stability was evaluated using the Lienard-Chipart stability criterion and the Runge-Kutta method.The results indicate that speed fluctuations occur within a specific range of input voltage and angular frequency,and the amplitude fluctuation region expands when load variation is considered.Furthermore,the Poincare map and Lyapunov exponent are adopted to determine the oscillation distribution and dynamic characteristics in a typical region.Specifically,the chaos phenomenon mostly occurred at the edge of the unstable region with an increase in the load.In contrast,periodic conciliation is mainly concentrated within the unstable region.
