Eddy current dampers (ECDs) have emerged as highly desirable solutions for vibration control due to theirexceptional damping performance and durability. However, the existing constitutive models present challenges tot...Eddy current dampers (ECDs) have emerged as highly desirable solutions for vibration control due to theirexceptional damping performance and durability. However, the existing constitutive models present challenges tothe widespread implementation of ECD technology, and there is limited availability of finite element analysis (FEA)software capable of accurately modeling the behavior of ECDs. This study addresses these issues by developing anewconstitutivemodel that is both easily understandable and user-friendly for FEAsoftware. By utilizing numericalresults obtained from electromagnetic FEA, a novel power law constitutive model is proposed to capture thenonlinear behavior of ECDs. The effectiveness of the power law constitutive model is validated throughmechanicalproperty tests and numerical seismic analysis. Furthermore, a detailed description of the application process ofthe power law constitutive model in ANSYS FEA software is provided. To facilitate the preliminary design ofECDs, an analytical derivation of energy dissipation and parameter optimization for ECDs under harmonicmotionis performed. The results demonstrate that the power law constitutive model serves as a viable alternative forconducting dynamic analysis using FEA and optimizing parameters for ECDs.展开更多
“The Law of Life”is one of Jack London’s representative works,depicting the story of an elderly Native American abandoned by his family,alone and waiting for life to fade away.This paper,based on narrative theory,a...“The Law of Life”is one of Jack London’s representative works,depicting the story of an elderly Native American abandoned by his family,alone and waiting for life to fade away.This paper,based on narrative theory,aims to explore how the author employs narrative techniques to present the image of the old man in the short story.The narrative techniques of dual focalization and dual narrative timelines in the text demonstrate the abandonment of the old man’s homeland and his inescapable death under a naturalistic view of life and reflect a desolate life picture of resignation towards death under naturalistic determinism,depicting a grim elderly world under the naturalistic concept of“survival of the fittest.”Studying this short story helps us reflect on the living conditions of the elderly and provides insights into how to better care for the elderly population amid the global trend of aging.展开更多
Based on the results of drilling,tests and simulation experiments,the shales of the Cretaceous Qingshankou Formation in the Gulong Sag of the Songliao Basin are discussed with respect to hydrocarbon generation evoluti...Based on the results of drilling,tests and simulation experiments,the shales of the Cretaceous Qingshankou Formation in the Gulong Sag of the Songliao Basin are discussed with respect to hydrocarbon generation evolution,shale oil occurrence,and pore/fracture evolution mechanism.In conjunction with a substantial amount of oil testing and production data,the Gulong shale oil enrichment layers are evaluated and the production behaviors and decline law are analyzed.The results are drawn in four aspects.First,the Gulong shales are in the stage of extensive hydrocarbon expulsion when R_(0) is 1.0%-1.2%,with the peak hydrocarbon expulsion efficiency of 49.5%approximately.In the low-medium maturity stage,shale oil migrates from kerogen to rocks and organic pores/fractures.In the medium-high maturity stage,shale oil transforms from adsorbed state to free state.Second,the clay mineral intergranular pores/fractures,dissolution pores,and organic pores make up the majority of the pore structure.During the transformation,clay minerals undergo significant intergranular pore/fracture development between the minerals such as illite and illite/smectite mixed layer.A network of pores/fractures is formed by organic matter cracking.Third,free hydrocarbon content,effective porosity,total porosity,and brittle mineral content are the core indicators for the evaluation of shale oil enrichment layers.Class-I layers are defined as free hydrocarbon content equal or greater than 6.0 mg/g,effective porosity equal or greater than 3.5%,total porosity equal or greater than 8.0%,and brittle mineral content equal or greater than 50%.It is believed that the favourable oil layers are Q2-Q3 and Q8-Q9.Fourth,the horizontal wells in the core area of the light oil zone exhibit a high cumulative production in the first year,and present a hyperbolic production decline pattern,with the decline index of 0.85-0.95,the first-year decline rate of 14.5%-26.5%,and the single-well estimated ultimate recovery(EUR)greater than 2.0×10^(4)t.In practical exploration and production,more efforts will be devoted to the clarification of hydrocarbon generation and expulsion mechanisms,accurate testing of porosity and hydrocarbon content/phase of shale under formation conditions,precise delineation of the boundary of enrichment area,relationship between mechanical properties and stimulated reservoir volume,and enhanced oil recovery,in order to improve the EUR and achieve a large-scale,efficient development of shale oil.展开更多
This paper addresses the issue of the formulation of weak solutions to systems of nonlinear hyperbolic conservation laws as integral balance laws.The basic idea is that the“meaningful objects”are the fluxes,evaluate...This paper addresses the issue of the formulation of weak solutions to systems of nonlinear hyperbolic conservation laws as integral balance laws.The basic idea is that the“meaningful objects”are the fluxes,evaluated across domain boundaries over time intervals.The fundamental result in this treatment is the regularity of the flux trace in the multi-dimensional setting.It implies that a weak solution indeed satisfies the balance law.In fact,it is shown that the flux is Lipschitz continuous with respect to suitable perturbations of the boundary.It should be emphasized that the weak solutions considered here need not be entropy solutions.Furthermore,the assumption imposed on the flux f(u)is quite minimal-just that it is locally bounded.展开更多
The study of a flexible body immersed in a flowing medium is one of the best way to find its aerodynamic shape.This Letter revisited the problem that was first studied by Alben et al.(Nature 420,479–481,2002).To dete...The study of a flexible body immersed in a flowing medium is one of the best way to find its aerodynamic shape.This Letter revisited the problem that was first studied by Alben et al.(Nature 420,479–481,2002).To determine the aerodynamic shape of the fibre,a simpler approach is proposed.A universal drag scaling law is obtained and the universality of the Alben-Shelley-Zhang scaling law is confirmed by using dimensional analysis.A complete Maple code is provided for finding aerodynamic shape of the fibre in the flowing medium.展开更多
Adolescents’physical and mental development has obvious age-stage characteristics.Therefore,before the implementation of physical education teaching,it is necessary to fully analyze the laws of adolescents’psycholog...Adolescents’physical and mental development has obvious age-stage characteristics.Therefore,before the implementation of physical education teaching,it is necessary to fully analyze the laws of adolescents’psychological development and fully understand the laws of adolescents’physical development and exercise acquisition.The purpose of this study is to start from the actual needs of physical education teaching and to fully understand the laws of psychological development of adolescent groups.After the review and analysis,the law of adolescents’sports acquisition is summarized and summarized,so as to form the system of adolescents’psychological development and sports acquisition law in physical education teaching,lay a good foundation for physical education teachers to implement teaching on the teaching objects of adolescent students in a targeted and efficient manner,and ultimately promote the benign development of school sports.展开更多
Soil strain is the key parameter to control the elasto-plastic deformation and even the failure processes.To overcome the defect that the strain of the model soil is always smaller than that of the prototype in Iai′s...Soil strain is the key parameter to control the elasto-plastic deformation and even the failure processes.To overcome the defect that the strain of the model soil is always smaller than that of the prototype in Iai′s generalized scaling law(GSL),a modified scaling law was proposed based on Iai′s GSL to secure the same dynamic shear strain between the centrifuge model and the prototype by modulating the amplitude and frequency of the input motion at the base.A suite of dynamic centrifuge model tests of dry sand level ground was conducted with the same overall scaling factor(λ=200)under different centrifugal accelerations by using the technique of“modeling of models”to validate the modified GSL.The test results show that the modified GSL could achieve the same dynamic strain in model as that of the prototype,leading to better modeling for geotechnical problems where dynamic strain dominates the response or failure of soils.Finally,the applicability of the proposed scaling law and possible constraints on geometry scaling due to the capability limits of existing centrifuge shaking tables are discussed.展开更多
Current lithium-ion batteries(LIBs)rely on organic liquid electrolytes that pose significant risks due to their flammability and toxicity.The potential for environmental pollution and explosions resulting from battery...Current lithium-ion batteries(LIBs)rely on organic liquid electrolytes that pose significant risks due to their flammability and toxicity.The potential for environmental pollution and explosions resulting from battery damage or fracture is a critical concern.Water-based(aqueous)electrolytes have been receiving attention as an alternative to organic electrolytes.However,a narrow electrochemicalstability window,water decomposition,and the consequent low battery operating voltage and energy density hinder the practical use of aqueous electrolytes.Therefore,developing novel aqueous electrolytes for sustainable,safe,high-performance LIBs remains challenging.This Review first commences by summarizing the roles and requirements of electrolytes–separators and then delineates the progression of aqueous electrolytes for LIBs,encompassing aqueous liquid and gel electrolyte development trends along with detailed principles of the electrolytes.These aqueous electrolytes are progressed based on strategies using superconcentrated salts,concentrated diluents,polymer additives,polymer networks,and artificial passivation layers,which are used for suppressing water decomposition and widening the electrochemical stability window of water of the electrolytes.In addition,this Review discusses potential strategies for the implementation of aqueous Li-metal batteries with improved electrolyte–electrode interfaces.A comprehensive understanding of each strategy in the aqueous system will assist in the design of an aqueous electrolyte and the development of sustainable and safe high-performance batteries.展开更多
Law enforcement remains to be the main strategy used to combat poaching and account for high budget share in protected area management. Studies on efficiency of wildlife law enforcement in the protected areas are limi...Law enforcement remains to be the main strategy used to combat poaching and account for high budget share in protected area management. Studies on efficiency of wildlife law enforcement in the protected areas are limited. This study analyzed economic efficiency of wildlife law enforcement in terms of resource used and output generated using three different protected areas (PAs) of Serengeti ecosystem namely Serengeti National Park (SENAPA), Ikorongo/Grumeti Game Reserves (IGGR) and Ikona Wildlife Management Area (IWMA). Three years (2010-2012) monthly data on wildlife law enforcement inputs and outputs were collected from respective PAs authorities and supplemented with key informant interviews and secondary data. Questionnaire surveys were conducted to wildlife law enforcement staff. Shadow prices for non-marketed inputs were estimated, and market prices for marketed inputs. Data Envelopment Analysis (DEA) was used to estimate economic efficiency using Variable Return to Scale (VRS) and Constant Return to Scale (CCR) assumptions. Results revealed that wildlife law enforcement in all PAs was economically inefficient, with less inefficiency observed in IWMA. The less inefficiency in IWMA is likely attributed to existing sense of ownership and responsibility created through community-based conservation which resulted in to decrease in law enforcement costs. A slacks evaluation revealed a potential to reduce fuel consumption, number of patrol vehicles, ration and prosecution efforts at different magnitudes between studied protected areas. There is equal potential to recruit more rangers while maintaining the resting time. These finding forms the bases for monitoring and evaluation with respect to resource usage to enhance efficiency. It is further recommended to enhance community participation in conservation in SENAPA and IGGR to lower law enforcement costs. Collaboration between protected area, police and judiciary is fundamental to enhance enforcement efficiency. Despite old dataset, these findings are relevant since neither conservation policy nor institution framework has changed substantially in the last decade.展开更多
We investigate the low Mach number limit for the isentropic compressible NavierStokes equations with a revised Maxwell's law(with Galilean invariance) in R^(3). By applying the uniform estimates of the error syste...We investigate the low Mach number limit for the isentropic compressible NavierStokes equations with a revised Maxwell's law(with Galilean invariance) in R^(3). By applying the uniform estimates of the error system, it is proven that the solutions of the isentropic Navier-Stokes equations with a revised Maxwell's law converge to that of the incompressible Navier-Stokes equations as the Mach number tends to zero. Moreover, the convergence rates are also obtained.展开更多
Complex sustainability issues in the Anthropocene,with rapid globalization and global environmental changes,are increasingly interlinked between not only nearby systems but also distant systems.Tobler’s first law of ...Complex sustainability issues in the Anthropocene,with rapid globalization and global environmental changes,are increasingly interlinked between not only nearby systems but also distant systems.Tobler’s first law of geog-raphy(TFL)states“near things are more related than distant things”.Evidence suggests that TFL is not infallible for sustainability issues.Recently,the integrated framework of metacoupling(MCF;human-nature interactions within as well as between adjacent and distant systems)has been applied to analyze the interactions between nearby and distant coupled human and natural systems simultaneously.However,previous work has been scat-tered and fragmented.It is crucial to understand the extent to which TFL and MCF apply across pressing issues in sustainability.Therefore,we reviewed and synthesized sustainability literature that used TFL and MCF across seven major topics:land change,species migration,tourism,trade,agricultural development,conservation,and governance.Results indicate MCF had a much broader applicability than TFL for these topics.The literature using MCF generally did not or likely did not obey TFL,especially in trade,governance,and agricultural de-velopment.In the TFL literature,most topics obeyed TFL,except for species migration and trade.The findings suggest the need to rethink and further test TFL’s relevance to sustainability issues,and highlight the potential of MCF to address complex interactions between both adjacent and distant systems across the world for global sustainability.展开更多
The internal energy change of ideal gas does not depend on the volume and pressure. The internal energy change of real gas has not any relation with the volume and pressure, which had been proved. If the internal ener...The internal energy change of ideal gas does not depend on the volume and pressure. The internal energy change of real gas has not any relation with the volume and pressure, which had been proved. If the internal energy change had not any relation with the volume and pressure, we could confirm the first law of thermodynamics in theory. Simultaneously, the internal energy change is the state function that shall be able to be proved in theory. If the internal energy change depended on the volume and pressure, we could not prove that the internal energy change is the state function and the chemical thermodynamics theory is right. The extended or modified Bernoulli equation can be derived from the energy conservation law, and the internal energy change, heat, and friction are all considered in the derivation procedure. The extended Bernoulli equation could be applied to the flying aircraft and mechanical motion on the gravitational field, for instance, the rocket and airplane and so on. This paper also revises some wrong ideas, viewpoints, or concepts about the thermodynamics theory and Bernoulli equation.展开更多
This article aims to explore the intersection of law and literature,analyzing their connections and influences.First,the article introduces the definitions and basic characteristics of law and literature,emphasizing t...This article aims to explore the intersection of law and literature,analyzing their connections and influences.First,the article introduces the definitions and basic characteristics of law and literature,emphasizing their similarities and differences.Then,the article discusses how literary works involve legal issues and how law becomes the subject and background of literary works.In addition,the article studies the interaction between law and literature,exploring the impact of novels on legal practice,and how legal texts are rewritten and interpreted in literary works.Finally,the article summarizes the relationship between law and literature and offers some prospects and reflections.展开更多
At present,the legal remedies in terms of the right to equal employment in China are mainly related to private law,that is,laborers seek direct legal remedies for personality rights liability and infringement liabilit...At present,the legal remedies in terms of the right to equal employment in China are mainly related to private law,that is,laborers seek direct legal remedies for personality rights liability and infringement liability according to typical private law,supplemented by indirect remedies for labor contract liability under special private law.However,there are many challenges in private law remedies for the right to equal employment,which are manifested in the misunderstanding of the general tort identification of employment discrimination,the loopholes in the regulations on discriminatory employment,the imbalance in the burden of proof,and the limitation and alienation of the functions of civil liability and private law autonomy.The root of those problems lies in the fact that the nature of anti-employment discrimination law is not private law but social law.Equal employment involves both public and private interests,and it should be based on the public interest of society and adhere to the value orientation of prioritizing fairness while taking into account efficiency.Improving the legal relief mechanism for protecting the right to equal employment,with a focus on correcting private law with social law,is the solution to the dilemma.Specific measures include establishing the special tort liability system for equal employment,the legal mechanism against discriminatory labor contracts,the public-private integrated legal responsibility system,and an essentially fair system for the responsibility of adducing evidence.展开更多
Exploring the inner law of the economic operation of urbanization can understand the regulation mechanism of the optimal distribution of urban resource allocation. In this regard, we propose to explore and analyze the...Exploring the inner law of the economic operation of urbanization can understand the regulation mechanism of the optimal distribution of urban resource allocation. In this regard, we propose to explore and analyze the inner law of urbanization economic operation and its application. The study found that the urbanization economy originated from the urban agglomeration effect, which includes the agglomeration economic operation mechanism and spillover effect operation mechanism, based on which three kinds of inner laws of urbanization economic operation are explored, combined with the economic operation law, the non-equilibrium state of the declining cities are regulated and applied, and the results show that the analysis of the inner laws of urbanization economic operation has a direct significance in guiding the real economic process.展开更多
This paper proposes a new version of the high-resolution entropy-consistent(EC-Limited)flux for hyperbolic conservation laws based on a new minmod-type slope limiter.Firstly,we identify the numerical entropy productio...This paper proposes a new version of the high-resolution entropy-consistent(EC-Limited)flux for hyperbolic conservation laws based on a new minmod-type slope limiter.Firstly,we identify the numerical entropy production,a third-order differential term deduced from the previous work of Ismail and Roe[11].The corresponding dissipation term is added to the original Roe flux to achieve entropy consistency.The new,resultant entropy-consistent(EC)flux has a general and explicit analytical form without any corrective factor,making it easy to compute and a less-expensive method.The inequality constraints are imposed on the standard piece-wise quadratic reconstruction to enforce the pointwise values of bounded-type numerical solutions.We design the new minmod slope limiter as combining two separate limiters for left and right states.We propose the EC-Limited flux by adding this reconstruction data method to the primitive variables rather than to the conservative variables of the EC flux to preserve the equilibrium of the primitive variables.These resulting fluxes are easily applied to general hyperbolic conservation laws while having attractive features:entropy-stable,robust,and non-oscillatory.To illustrate the potential of these proposed fluxes,we show the applications to the Burgers equation and the Euler equations.展开更多
文摘Eddy current dampers (ECDs) have emerged as highly desirable solutions for vibration control due to theirexceptional damping performance and durability. However, the existing constitutive models present challenges tothe widespread implementation of ECD technology, and there is limited availability of finite element analysis (FEA)software capable of accurately modeling the behavior of ECDs. This study addresses these issues by developing anewconstitutivemodel that is both easily understandable and user-friendly for FEAsoftware. By utilizing numericalresults obtained from electromagnetic FEA, a novel power law constitutive model is proposed to capture thenonlinear behavior of ECDs. The effectiveness of the power law constitutive model is validated throughmechanicalproperty tests and numerical seismic analysis. Furthermore, a detailed description of the application process ofthe power law constitutive model in ANSYS FEA software is provided. To facilitate the preliminary design ofECDs, an analytical derivation of energy dissipation and parameter optimization for ECDs under harmonicmotionis performed. The results demonstrate that the power law constitutive model serves as a viable alternative forconducting dynamic analysis using FEA and optimizing parameters for ECDs.
文摘“The Law of Life”is one of Jack London’s representative works,depicting the story of an elderly Native American abandoned by his family,alone and waiting for life to fade away.This paper,based on narrative theory,aims to explore how the author employs narrative techniques to present the image of the old man in the short story.The narrative techniques of dual focalization and dual narrative timelines in the text demonstrate the abandonment of the old man’s homeland and his inescapable death under a naturalistic view of life and reflect a desolate life picture of resignation towards death under naturalistic determinism,depicting a grim elderly world under the naturalistic concept of“survival of the fittest.”Studying this short story helps us reflect on the living conditions of the elderly and provides insights into how to better care for the elderly population amid the global trend of aging.
基金Supported by the National Natural Science Foundation Project(42090020,42090025)Strategic Research of Oil and Gas Development Major Project of Ministry of Science and TechnologyPetroChina Scientific Research and Technological Development Project(2019E2601).
文摘Based on the results of drilling,tests and simulation experiments,the shales of the Cretaceous Qingshankou Formation in the Gulong Sag of the Songliao Basin are discussed with respect to hydrocarbon generation evolution,shale oil occurrence,and pore/fracture evolution mechanism.In conjunction with a substantial amount of oil testing and production data,the Gulong shale oil enrichment layers are evaluated and the production behaviors and decline law are analyzed.The results are drawn in four aspects.First,the Gulong shales are in the stage of extensive hydrocarbon expulsion when R_(0) is 1.0%-1.2%,with the peak hydrocarbon expulsion efficiency of 49.5%approximately.In the low-medium maturity stage,shale oil migrates from kerogen to rocks and organic pores/fractures.In the medium-high maturity stage,shale oil transforms from adsorbed state to free state.Second,the clay mineral intergranular pores/fractures,dissolution pores,and organic pores make up the majority of the pore structure.During the transformation,clay minerals undergo significant intergranular pore/fracture development between the minerals such as illite and illite/smectite mixed layer.A network of pores/fractures is formed by organic matter cracking.Third,free hydrocarbon content,effective porosity,total porosity,and brittle mineral content are the core indicators for the evaluation of shale oil enrichment layers.Class-I layers are defined as free hydrocarbon content equal or greater than 6.0 mg/g,effective porosity equal or greater than 3.5%,total porosity equal or greater than 8.0%,and brittle mineral content equal or greater than 50%.It is believed that the favourable oil layers are Q2-Q3 and Q8-Q9.Fourth,the horizontal wells in the core area of the light oil zone exhibit a high cumulative production in the first year,and present a hyperbolic production decline pattern,with the decline index of 0.85-0.95,the first-year decline rate of 14.5%-26.5%,and the single-well estimated ultimate recovery(EUR)greater than 2.0×10^(4)t.In practical exploration and production,more efforts will be devoted to the clarification of hydrocarbon generation and expulsion mechanisms,accurate testing of porosity and hydrocarbon content/phase of shale under formation conditions,precise delineation of the boundary of enrichment area,relationship between mechanical properties and stimulated reservoir volume,and enhanced oil recovery,in order to improve the EUR and achieve a large-scale,efficient development of shale oil.
基金the Institute of Applied Physics and Computational Mathematics,Beijing,for the hospitality and support.The second author is supported by the NSFC(Nos.11771054,12072042,91852207)the Sino-German Research Group Project(No.GZ1465)the National Key Project GJXM92579.
文摘This paper addresses the issue of the formulation of weak solutions to systems of nonlinear hyperbolic conservation laws as integral balance laws.The basic idea is that the“meaningful objects”are the fluxes,evaluated across domain boundaries over time intervals.The fundamental result in this treatment is the regularity of the flux trace in the multi-dimensional setting.It implies that a weak solution indeed satisfies the balance law.In fact,it is shown that the flux is Lipschitz continuous with respect to suitable perturbations of the boundary.It should be emphasized that the weak solutions considered here need not be entropy solutions.Furthermore,the assumption imposed on the flux f(u)is quite minimal-just that it is locally bounded.
基金supported by Xi’an University of Architecture and Technology(Grant No.002/2040221134).
文摘The study of a flexible body immersed in a flowing medium is one of the best way to find its aerodynamic shape.This Letter revisited the problem that was first studied by Alben et al.(Nature 420,479–481,2002).To determine the aerodynamic shape of the fibre,a simpler approach is proposed.A universal drag scaling law is obtained and the universality of the Alben-Shelley-Zhang scaling law is confirmed by using dimensional analysis.A complete Maple code is provided for finding aerodynamic shape of the fibre in the flowing medium.
文摘Adolescents’physical and mental development has obvious age-stage characteristics.Therefore,before the implementation of physical education teaching,it is necessary to fully analyze the laws of adolescents’psychological development and fully understand the laws of adolescents’physical development and exercise acquisition.The purpose of this study is to start from the actual needs of physical education teaching and to fully understand the laws of psychological development of adolescent groups.After the review and analysis,the law of adolescents’sports acquisition is summarized and summarized,so as to form the system of adolescents’psychological development and sports acquisition law in physical education teaching,lay a good foundation for physical education teachers to implement teaching on the teaching objects of adolescent students in a targeted and efficient manner,and ultimately promote the benign development of school sports.
基金National Natural Science Foundation of China under Grant Nos.51988101,51978613 and 52278374the Chinese Program of Introducing Talents of Discipline to University(the 111 Project,B18047)。
文摘Soil strain is the key parameter to control the elasto-plastic deformation and even the failure processes.To overcome the defect that the strain of the model soil is always smaller than that of the prototype in Iai′s generalized scaling law(GSL),a modified scaling law was proposed based on Iai′s GSL to secure the same dynamic shear strain between the centrifuge model and the prototype by modulating the amplitude and frequency of the input motion at the base.A suite of dynamic centrifuge model tests of dry sand level ground was conducted with the same overall scaling factor(λ=200)under different centrifugal accelerations by using the technique of“modeling of models”to validate the modified GSL.The test results show that the modified GSL could achieve the same dynamic strain in model as that of the prototype,leading to better modeling for geotechnical problems where dynamic strain dominates the response or failure of soils.Finally,the applicability of the proposed scaling law and possible constraints on geometry scaling due to the capability limits of existing centrifuge shaking tables are discussed.
基金the National Research Foundation(NRF)of Korea(No.2022R1A2B5B02002097),funded by the Korea government(MSIT).
文摘Current lithium-ion batteries(LIBs)rely on organic liquid electrolytes that pose significant risks due to their flammability and toxicity.The potential for environmental pollution and explosions resulting from battery damage or fracture is a critical concern.Water-based(aqueous)electrolytes have been receiving attention as an alternative to organic electrolytes.However,a narrow electrochemicalstability window,water decomposition,and the consequent low battery operating voltage and energy density hinder the practical use of aqueous electrolytes.Therefore,developing novel aqueous electrolytes for sustainable,safe,high-performance LIBs remains challenging.This Review first commences by summarizing the roles and requirements of electrolytes–separators and then delineates the progression of aqueous electrolytes for LIBs,encompassing aqueous liquid and gel electrolyte development trends along with detailed principles of the electrolytes.These aqueous electrolytes are progressed based on strategies using superconcentrated salts,concentrated diluents,polymer additives,polymer networks,and artificial passivation layers,which are used for suppressing water decomposition and widening the electrochemical stability window of water of the electrolytes.In addition,this Review discusses potential strategies for the implementation of aqueous Li-metal batteries with improved electrolyte–electrode interfaces.A comprehensive understanding of each strategy in the aqueous system will assist in the design of an aqueous electrolyte and the development of sustainable and safe high-performance batteries.
文摘Law enforcement remains to be the main strategy used to combat poaching and account for high budget share in protected area management. Studies on efficiency of wildlife law enforcement in the protected areas are limited. This study analyzed economic efficiency of wildlife law enforcement in terms of resource used and output generated using three different protected areas (PAs) of Serengeti ecosystem namely Serengeti National Park (SENAPA), Ikorongo/Grumeti Game Reserves (IGGR) and Ikona Wildlife Management Area (IWMA). Three years (2010-2012) monthly data on wildlife law enforcement inputs and outputs were collected from respective PAs authorities and supplemented with key informant interviews and secondary data. Questionnaire surveys were conducted to wildlife law enforcement staff. Shadow prices for non-marketed inputs were estimated, and market prices for marketed inputs. Data Envelopment Analysis (DEA) was used to estimate economic efficiency using Variable Return to Scale (VRS) and Constant Return to Scale (CCR) assumptions. Results revealed that wildlife law enforcement in all PAs was economically inefficient, with less inefficiency observed in IWMA. The less inefficiency in IWMA is likely attributed to existing sense of ownership and responsibility created through community-based conservation which resulted in to decrease in law enforcement costs. A slacks evaluation revealed a potential to reduce fuel consumption, number of patrol vehicles, ration and prosecution efforts at different magnitudes between studied protected areas. There is equal potential to recruit more rangers while maintaining the resting time. These finding forms the bases for monitoring and evaluation with respect to resource usage to enhance efficiency. It is further recommended to enhance community participation in conservation in SENAPA and IGGR to lower law enforcement costs. Collaboration between protected area, police and judiciary is fundamental to enhance enforcement efficiency. Despite old dataset, these findings are relevant since neither conservation policy nor institution framework has changed substantially in the last decade.
基金Yuxi HU was supported by the NNSFC (11701556)the Yue Qi Young Scholar ProjectChina University of Mining and Technology (Beijing)。
文摘We investigate the low Mach number limit for the isentropic compressible NavierStokes equations with a revised Maxwell's law(with Galilean invariance) in R^(3). By applying the uniform estimates of the error system, it is proven that the solutions of the isentropic Navier-Stokes equations with a revised Maxwell's law converge to that of the incompressible Navier-Stokes equations as the Mach number tends to zero. Moreover, the convergence rates are also obtained.
基金We thank the National Science Foundation(Grants No.1924111,2033507 and 2118329)Michigan AgBioResearch for financial support.
文摘Complex sustainability issues in the Anthropocene,with rapid globalization and global environmental changes,are increasingly interlinked between not only nearby systems but also distant systems.Tobler’s first law of geog-raphy(TFL)states“near things are more related than distant things”.Evidence suggests that TFL is not infallible for sustainability issues.Recently,the integrated framework of metacoupling(MCF;human-nature interactions within as well as between adjacent and distant systems)has been applied to analyze the interactions between nearby and distant coupled human and natural systems simultaneously.However,previous work has been scat-tered and fragmented.It is crucial to understand the extent to which TFL and MCF apply across pressing issues in sustainability.Therefore,we reviewed and synthesized sustainability literature that used TFL and MCF across seven major topics:land change,species migration,tourism,trade,agricultural development,conservation,and governance.Results indicate MCF had a much broader applicability than TFL for these topics.The literature using MCF generally did not or likely did not obey TFL,especially in trade,governance,and agricultural de-velopment.In the TFL literature,most topics obeyed TFL,except for species migration and trade.The findings suggest the need to rethink and further test TFL’s relevance to sustainability issues,and highlight the potential of MCF to address complex interactions between both adjacent and distant systems across the world for global sustainability.
文摘The internal energy change of ideal gas does not depend on the volume and pressure. The internal energy change of real gas has not any relation with the volume and pressure, which had been proved. If the internal energy change had not any relation with the volume and pressure, we could confirm the first law of thermodynamics in theory. Simultaneously, the internal energy change is the state function that shall be able to be proved in theory. If the internal energy change depended on the volume and pressure, we could not prove that the internal energy change is the state function and the chemical thermodynamics theory is right. The extended or modified Bernoulli equation can be derived from the energy conservation law, and the internal energy change, heat, and friction are all considered in the derivation procedure. The extended Bernoulli equation could be applied to the flying aircraft and mechanical motion on the gravitational field, for instance, the rocket and airplane and so on. This paper also revises some wrong ideas, viewpoints, or concepts about the thermodynamics theory and Bernoulli equation.
文摘This article aims to explore the intersection of law and literature,analyzing their connections and influences.First,the article introduces the definitions and basic characteristics of law and literature,emphasizing their similarities and differences.Then,the article discusses how literary works involve legal issues and how law becomes the subject and background of literary works.In addition,the article studies the interaction between law and literature,exploring the impact of novels on legal practice,and how legal texts are rewritten and interpreted in literary works.Finally,the article summarizes the relationship between law and literature and offers some prospects and reflections.
基金the research result of the Scientific Research Fund Project(supported by the Special Funds for Basic Scientific Research for Central Universities)of Renmin University of China,“Research on Solving the Dilemma of Private Law Relief for the Right to Equal Employment in Social Law”(Project Approval No.21XNH019)。
文摘At present,the legal remedies in terms of the right to equal employment in China are mainly related to private law,that is,laborers seek direct legal remedies for personality rights liability and infringement liability according to typical private law,supplemented by indirect remedies for labor contract liability under special private law.However,there are many challenges in private law remedies for the right to equal employment,which are manifested in the misunderstanding of the general tort identification of employment discrimination,the loopholes in the regulations on discriminatory employment,the imbalance in the burden of proof,and the limitation and alienation of the functions of civil liability and private law autonomy.The root of those problems lies in the fact that the nature of anti-employment discrimination law is not private law but social law.Equal employment involves both public and private interests,and it should be based on the public interest of society and adhere to the value orientation of prioritizing fairness while taking into account efficiency.Improving the legal relief mechanism for protecting the right to equal employment,with a focus on correcting private law with social law,is the solution to the dilemma.Specific measures include establishing the special tort liability system for equal employment,the legal mechanism against discriminatory labor contracts,the public-private integrated legal responsibility system,and an essentially fair system for the responsibility of adducing evidence.
文摘Exploring the inner law of the economic operation of urbanization can understand the regulation mechanism of the optimal distribution of urban resource allocation. In this regard, we propose to explore and analyze the inner law of urbanization economic operation and its application. The study found that the urbanization economy originated from the urban agglomeration effect, which includes the agglomeration economic operation mechanism and spillover effect operation mechanism, based on which three kinds of inner laws of urbanization economic operation are explored, combined with the economic operation law, the non-equilibrium state of the declining cities are regulated and applied, and the results show that the analysis of the inner laws of urbanization economic operation has a direct significance in guiding the real economic process.
基金the National Natural Science Found Project of China through project number 11971075.
文摘This paper proposes a new version of the high-resolution entropy-consistent(EC-Limited)flux for hyperbolic conservation laws based on a new minmod-type slope limiter.Firstly,we identify the numerical entropy production,a third-order differential term deduced from the previous work of Ismail and Roe[11].The corresponding dissipation term is added to the original Roe flux to achieve entropy consistency.The new,resultant entropy-consistent(EC)flux has a general and explicit analytical form without any corrective factor,making it easy to compute and a less-expensive method.The inequality constraints are imposed on the standard piece-wise quadratic reconstruction to enforce the pointwise values of bounded-type numerical solutions.We design the new minmod slope limiter as combining two separate limiters for left and right states.We propose the EC-Limited flux by adding this reconstruction data method to the primitive variables rather than to the conservative variables of the EC flux to preserve the equilibrium of the primitive variables.These resulting fluxes are easily applied to general hyperbolic conservation laws while having attractive features:entropy-stable,robust,and non-oscillatory.To illustrate the potential of these proposed fluxes,we show the applications to the Burgers equation and the Euler equations.