Methane generation in landfills and its inadequate management represent the major avoidable source of anthropogenic methane today. This paper models methane production and the potential resources expected (electrical ...Methane generation in landfills and its inadequate management represent the major avoidable source of anthropogenic methane today. This paper models methane production and the potential resources expected (electrical energy production and potential carbon credits from avoided CH4 emissions) from its proper management in a municipal solid waste landfill located in Ouagadougou, Burkina Faso. The modeling was carried out using two first-order decay (FOD) models (LandGEM V3.02 and SWANA) using parameters evaluated on the basis of the characteristics of the waste admitted to the landfill and weather data for the site. At the same time, production data have been collected since 2016 in order to compare them with the model results. The results obtained from these models were compared to experimental one. For the simulation of methane production, the SWANA model showed better consistency with experimental data, with a coefficient of determination (R²) of 0.59 compared with the LandGEM model, which obtained a coefficient of 0.006. Thus, despite the low correlation values linked to the poor consistency of experimental data, the SWANA model models methane production much better than the LandGEM model. Thus, despite the low correlation values linked to the poor consistency of the experimental data, the SWANA model models methane production much better than the LandGEM V3.02 model. It was noted that the poor consistency of the experimental data justifies these low coefficients, and that they can be improved in the future thanks to ongoing in situ measurements. According to the SWANA model prediction, in 27 years of operation a biogas plant with 33% electrical efficiency using biogas from the Polesgo landfill would avoid 1,340 GgCO2e. Also, the evaluation of revenues due to electricity and carbon credit gave a total revenue derived from methane production of US$27.38 million at a cost of US$10.5/tonne CO2e.展开更多
In this paper,we present a novel first-order digitalΣΔconverter tailored for digital-to-analog applications,focusing on achieving both high yield and reduced silicon estate.Our approach incorporates a substantial le...In this paper,we present a novel first-order digitalΣΔconverter tailored for digital-to-analog applications,focusing on achieving both high yield and reduced silicon estate.Our approach incorporates a substantial level of dithering noise into the input signal,strategically aimed at mitigating the spurious frequencies commonly encountered in such converters.Validation of our design is performed through simulations using a high-level simulator specialized in mixed-signal circuit analysis.The results underscore the enhanced performance of our circuit,especially in reducing spurious frequencies,highlighting its efficiency and effectiveness.The final circuit exhibits an effective number of bits of 13.展开更多
Long-term responses of floating structures pose a great concern in their design phase. Existing approaches for addressing long-term extreme responses are extremely cumbersome for adoption. This work aims to develop an...Long-term responses of floating structures pose a great concern in their design phase. Existing approaches for addressing long-term extreme responses are extremely cumbersome for adoption. This work aims to develop an approach for the long-term extreme-response analysis of floating structures. A modified gradient-based retrieval algorithm in conjunction with the inverse first-order reliability method(IFORM) is proposed to enable the use of convolution models in long-term extreme analysis of structures with an analytical formula of response amplitude operator(RAO). The proposed algorithm ensures convergence stability and iteration accuracy and exhibits a higher computational efficiency than the traditional backtracking method. However, when the RAO of general offshore structures cannot be analytically expressed, the convolutional integration method fails to function properly. A numerical discretization approach is further proposed for offshore structures in the case when the analytical expression of the RAO is not feasible. Through iterative discretization of environmental contours(ECs) and RAOs, a detailed procedure is proposed to calculate the long-term response extremes of offshore structures. The validity and accuracy of the proposed approach are tested using a floating offshore wind turbine as a numerical example. The long-term extreme heave responses of various return periods are calculated via the IFORM in conjunction with a numerical discretization approach. The environmental data corresponding to N-year structural responses are located inside the ECs, which indicates that the selection of design points directly along the ECs yields conservative design results.展开更多
This paper introduces a novel approach for parameter sensitivity evaluation and efficient slope reliability analysis based on quantile-based first-order second-moment method(QFOSM).The core principles of the QFOSM are...This paper introduces a novel approach for parameter sensitivity evaluation and efficient slope reliability analysis based on quantile-based first-order second-moment method(QFOSM).The core principles of the QFOSM are elucidated geometrically from the perspective of expanding ellipsoids.Based on this geometric interpretation,the QFOSM is further extended to estimate sensitivity indices and assess the significance of various uncertain parameters involved in the slope system.The proposed method has the advantage of computational simplicity,akin to the conventional first-order second-moment method(FOSM),while providing estimation accuracy close to that of the first-order reliability method(FORM).Its performance is demonstrated with a numerical example and three slope examples.The results show that the proposed method can efficiently estimate the slope reliability and simultaneously evaluate the sensitivity of the uncertain parameters.The proposed method does not involve complex optimization or iteration required by the FORM.It can provide a valuable complement to the existing approximate reliability analysis methods,offering rapid sensitivity evaluation and slope reliability analysis.展开更多
Investigating natural-inspired applications is a perennially appealing subject for scientists. The current increase in the speed of natural-origin structure growth may be linked to their superior mechanical properties...Investigating natural-inspired applications is a perennially appealing subject for scientists. The current increase in the speed of natural-origin structure growth may be linked to their superior mechanical properties and environmental resilience. Biological composite structures with helicoidal schemes and designs have remarkable capacities to absorb impact energy and withstand damage. However, there is a dearth of extensive study on the influence of fiber redirection and reorientation inside the matrix of a helicoid structure on its mechanical performance and reactivity. The present study aimed to explore the static and transient responses of a bio-inspired helicoid laminated composite(B-iHLC) shell under the influence of an explosive load using an isomorphic method. The structural integrity of the shell is maintained by a viscoelastic basis known as the Pasternak foundation, which encompasses two coefficients of stiffness and one coefficient of damping. The equilibrium equations governing shell dynamics are obtained by using Hamilton's principle and including the modified first-order shear theory,therefore obviating the need to employ a shear correction factor. The paper's model and approach are validated by doing numerical comparisons with respected publications. The findings of this study may be used in the construction of military and civilian infrastructure in situations when the structure is subjected to severe stresses that might potentially result in catastrophic collapse. The findings of this paper serve as the foundation for several other issues, including geometric optimization and the dynamic response of similar mechanical structures.展开更多
Using Euler’s first-order explicit(EE)method and the peridynamic differential operator(PDDO)to discretize the time and internal crystal-size derivatives,respectively,the Euler’s first-order explicit method–peridyna...Using Euler’s first-order explicit(EE)method and the peridynamic differential operator(PDDO)to discretize the time and internal crystal-size derivatives,respectively,the Euler’s first-order explicit method–peridynamic differential operator(EE–PDDO)was obtained for solving the one-dimensional population balance equation in crystallization.Four different conditions during crystallization were studied:size-independent growth,sizedependent growth in a batch process,nucleation and size-independent growth,and nucleation and size-dependent growth in a continuous process.The high accuracy of the EE–PDDO method was confirmed by comparing it with the numerical results obtained using the second-order upwind and HR-van methods.The method is characterized by non-oscillation and high accuracy,especially in the discontinuous and sharp crystal size distribution.The stability of the EE–PDDO method,choice of weight function in the PDDO method,and optimal time step are also discussed.展开更多
Two-plasmon-decay instability(TPD)poses a critical target preheating risk in direct-drive inertial confinement fusion.In this paper,TPD collectively driven by dual laser beams consisting of a normal-incidence laser be...Two-plasmon-decay instability(TPD)poses a critical target preheating risk in direct-drive inertial confinement fusion.In this paper,TPD collectively driven by dual laser beams consisting of a normal-incidence laser beam(Beam-N)and a large-angle-incidence laser beam(Beam-L)is investigated via particle-in-cell simulations.It is found that significant TPD growth can develop in this regime at previously unexpected low laser intensities if the intensity of Beam-L exceeds the large-angle-incidence threshold.Both beams contribute to the growth of TPD in a“seed-amplification”manner in which the absolute instability driven by Beam-L provides the seeds that are convectively amplified by Beam-N,making TPD energetically important and causing significant pump depletion and hot-electron generation.展开更多
Weak radiative hyperon decays represent a rich interplay between weak interactions and the internal structure of baryons,offering profound insights into Quantum Chromodynamics and weak interactions.Recent experimental...Weak radiative hyperon decays represent a rich interplay between weak interactions and the internal structure of baryons,offering profound insights into Quantum Chromodynamics and weak interactions.Recent experimental observations,particularly from BESIII,have revealed deviations from theoretical predictions.These deviations could signal new physics or the need for refined theoretical models incorporating intermediate resonance effects.This review discusses recent theoretical advancements and key experimental findings,focusing on recent measurements from BESIII and their implications for strong interactions and baryon structure.展开更多
A state-of-the-art detector array with a digital data acquisition system has been developed for charged-particle decay studies,includingβ-delayed protons,αdecay,and direct proton emissions from exotic proton-rich nu...A state-of-the-art detector array with a digital data acquisition system has been developed for charged-particle decay studies,includingβ-delayed protons,αdecay,and direct proton emissions from exotic proton-rich nuclei.The digital data acquisition system enables precise synchronization and processing of complex signals from various detectors,such as plastic scintillators,silicon detectors,and germaniumγdetectors.The system's performance was evaluated using theβdecay of^(32)Ar and its neighboring nuclei,produced via projectile fragmentation at the first Radioactive Ion Beam Line in Lanzhou(RIBLL1).Key measurements,including the half-life,charged-particle spectrum,andγ-ray spectrum,were obtained and compared with previous results for validation.Using the implantation–decay method,the isotopes of interest were implanted into two doublesided silicon strip detectors,where their subsequent decays were measured and correlated with preceding implantations using both position and time information.This detection system has potential for further applications,including the study ofβ-delayed charged-particle decay and direct proton emissions from even more exotic proton-rich nuclei.展开更多
William Faulkner’s Southern Gothic style features fragmented narratives and rich symbolism that explore characters’psychological complexity and the decay of Southern society.In his seminal work exploring Emily Grier...William Faulkner’s Southern Gothic style features fragmented narratives and rich symbolism that explore characters’psychological complexity and the decay of Southern society.In his seminal work exploring Emily Grierson’s tragic life,Faulkner employs a rich symbolic system that transcends mere literary decoration,instead functioning as a complex interpretative lens through which the disintegration of traditional Southern social structures can be understood.This paper argues that the symbolic framework in the narrative not only shapes Emily’s personal tragedy but also serves as a profound metaphorical representation of the collapse of the old Southern civilization-a system marked by rigid social hierarchies,racial tensions,and the slow erosion of aristocratic ideals in the face of inevitable social transformation.By dissecting the intricate symbolic elements-from the decaying mansion to the gothic imagery of death and preservation-this analysis reveals how Faulkner’s symbolic methodology becomes a nuanced historical and psychological commentary on the South’s traumatic transition from an antebellum past to a modernizing present.展开更多
Vanadium nitride(VN)is a promising pseudocapacitive material due to the high theoretical capacity,rapid redox Faradaic kinetics,and appropriate potential window.Although VN shows large pseudocapacitance in alkaline el...Vanadium nitride(VN)is a promising pseudocapacitive material due to the high theoretical capacity,rapid redox Faradaic kinetics,and appropriate potential window.Although VN shows large pseudocapacitance in alkaline electrolytes,the electrochemical instability and capacity degradation of VN electrode materials present significant challenges for practical applications.Herein,the capacitance decay mechanism of VN is investigated and a simple strategy to improve cycling stability of VN supercapacitor electrodes is proposed by introducing VO_(4)^(3-)anion in KOH electrolytes.Our results show that the VN electrode is electrochemical stabilization between-1.0and-0.4 V(vs.Hg/Hg O reference electrode)in 1.0 MKOH electrolyte,but demonstrates irreversible oxidation and fast capacitance decay in the potential range of-0.4 to0 V.In situ electrochemical measurements reveal that the capacitance decay of VN from-0.4 to 0 V is ascribed to the irreversible oxidation of vanadium(V)of N–V–O species by oxygen(O)of OH^(-).The as-generated oxidization species are subsequently dissolved into KOH electrolytes,thereby undermining the electrochemical stability of VN.However,this irreversible oxidation process could be hindered by introducing VO_(4)^(3-)in KOH electrolytes.A high volumetric specific capacitance of671.9 F.cm^(-3)(1 A.cm^(-3))and excellent cycling stability(120.3%over 1000 cycles)are achieved for VN nanorod electrode in KOH electrolytes containing VO_(4)^(3-).This study not only elucidates the failure mechanism of VN supercapacitor electrodes in alkaline electrolytes,but also provides new insights into enhancing pseudocapacitive energy storage of VN-based electrode materials.展开更多
In this study,we explore the impact of state-of-the-art laser fields on theαdecay half-life of deformed ground-state odd-A nuclei within the proton number range of 52–107.The calculations show that the presence of a...In this study,we explore the impact of state-of-the-art laser fields on theαdecay half-life of deformed ground-state odd-A nuclei within the proton number range of 52–107.The calculations show that the presence of a laser field modulates theαdecay half-life by altering theαdecay penetration probability within a limited range.Moreover,the variance in the penetration probability rate of change between even–odd and odd–even nuclei is investigated.Furthermore,we investigate the rate of change of the penetration probability for the same parent nucleus with different neutron numbers,based on the characteristics of the odd-A nucleus.We found that the influence of the laser field on the penetration probability is determined by both the shell effect and odd–even staggering.This research contributes to the understanding of nuanced interactions between laser fields and nuclear decay processes.Therefore,valuable insights for future experiments in laser–nuclear physics are attainable using this study.展开更多
[Objectives] To investigate the species diversity of wood-decaying fungi in karst regions of southwest China. [Methods] The karst core regions of southwest China, specifically Guizhou, Guangxi, and Yunnan, were invest...[Objectives] To investigate the species diversity of wood-decaying fungi in karst regions of southwest China. [Methods] The karst core regions of southwest China, specifically Guizhou, Guangxi, and Yunnan, were investigated for the first time to analyze the species diversity characteristics of wood-decaying fungi in this area. This analysis was conducted through a comprehensive 5-year field investigation and systematic identification process. [Results] The wood-decaying fungi exhibited a distinctive species composition and distribution pattern within karst habitats, encompassing significant groups such as Polyporaceae and Hymenochaetaceae. Furthermore, these fungi demonstrated varying functional characteristics across the two ecological types of standing tree decay and wood decay. It was observed that wood-decaying fungi had a significant impact on the material cycle within karst ecosystems by degrading lignin and cellulose. Furthermore, the distribution of species diversity was closely associated with the characteristics of karst geomorphology and the types of vegetation. [Conclusions] This study not only addresses the lack of background data regarding wood-decaying fungi resources in karst regions, but also elucidates the maintenance mechanisms of fragile ecosystems from the perspective of decomposers. It provides a scientific foundation for biodiversity conservation, the prevention and control of forest diseases, and sustainable ecological management in karst regions.展开更多
The α-nucleus interaction is crucial in the description of α decay. Recently, we developed a pocket-type dynamical doublefolding potential(DDFP) that effectively incorporates both the surface-medium effect and inter...The α-nucleus interaction is crucial in the description of α decay. Recently, we developed a pocket-type dynamical doublefolding potential(DDFP) that effectively incorporates both the surface-medium effect and interior Pauli repulsion in α decay [H. Zheng et al., Phys. Rev. C 109, L011301(2024)]. This potential results in a pocket geometry within the nuclear surface region, which is consistent with the α-clustering characteristics predicted by microscopic calculations. In this study, the accuracy of the pocket-type DDFP was validated via systematic calculations of α-decay half-lives and an extended evaluation of the nuclear charge radii of the daughter nuclei. The results demonstrate good agreement with the experimental data for both quantities, thereby confirming the reliability of the DDFP model. Compared with calculations that use α-nucleus interactions derived from conventional double-folding procedures, DDFP employs fewer adjustable parameters to achieve a more accurate description of the charge radii based on the experimental α-decay energies.展开更多
Cauchy problem for the linearized bipolar isentropic Navier-Stokes-Poisson system in R^(2) is studied.Through the reformulation of unknown functions,we change the formal system into a linearized Navier-Stokes system a...Cauchy problem for the linearized bipolar isentropic Navier-Stokes-Poisson system in R^(2) is studied.Through the reformulation of unknown functions,we change the formal system into a linearized Navier-Stokes system and a unipolar Navier-Stokes-Poisson system.Based on a delicate analysis of the corresponding Green function,L^(2) decay estimate of the solution is obtained.展开更多
This paper studies the global existence and large-time behaviors of weak solutions to the kinetic particle model coupled with the incompressible Navier-Stokes equations in IR3.First,we obtain the global weak solution ...This paper studies the global existence and large-time behaviors of weak solutions to the kinetic particle model coupled with the incompressible Navier-Stokes equations in IR3.First,we obtain the global weak solution using the characteristic and energy methods.Then,under the small assumption of the mass of the particle,we show that the solutions decay at the algebraic time-decay rate.Finally,it is also proved that the above rate is optimal.It should be remarked that if the particle in the coupled system vanishes(i.e.f=O),our works coincide with the classical results by Schonbek[32](J Amer Math Soc,1991,4:423-449),which can be regarded as a generalization from a single fuid model to the two-phase fluid one.展开更多
The paper is concerned with a class of elliptic equation with critical exponent and Dipole potential.More precisely,we make use of the refined Sobolev inequality with Morrey norm to obtain the existence and decay prop...The paper is concerned with a class of elliptic equation with critical exponent and Dipole potential.More precisely,we make use of the refined Sobolev inequality with Morrey norm to obtain the existence and decay properties of nonnegative radial ground state solutions.展开更多
The potential of high-intensity lasers to influence nuclear decay processes has attracted considerable interest.This study quantitatively evaluated the effects of high-intensity lasers on α decay and cluster radioact...The potential of high-intensity lasers to influence nuclear decay processes has attracted considerable interest.This study quantitatively evaluated the effects of high-intensity lasers on α decay and cluster radioactivity.Our calculations revealed that,among the parent nuclei investigated,^(144)Nd is the most susceptible to laser-induced alterations,primarily because of its relatively low decay energy.Additionally,circularly polarized lasers exhibit a greater impact on decay modifications than linearly polarized lasers.Given the limited time resolution of current detectors,it is essential to account for the timeaveraging effect of the laser.By incorporating the effects of circular polarization,time averaging,and angular averaging,our theoretical predictions indicated that the modification of^(144)Nd decay could reach 0.1%at an intensity of 10^(27)W/cm^(2).However,this intensity significantly exceeds the current laser capability of 10^(23)W/cm^(2),and the predicted modification of 0.1%remains below the detection threshold of contemporary measurement techniques.Observing laser-assistedαdecay and^(14)C cluster radioactivity will likely remain unfeasible until both ultrahigh laser intensities and significant advancements in experimental resolution are achieved.展开更多
Conventional PI control encounters some problems when dealing with large lag process in the presence of parameter uncertainties.For the typical first-order process,an observerbased linear active disturbance rejection ...Conventional PI control encounters some problems when dealing with large lag process in the presence of parameter uncertainties.For the typical first-order process,an observerbased linear active disturbance rejection control（LADRC） scheme is presented to cope with the difficulties,and a reduced-order observer scheme is proposed further.Some quantitative dynamic results with regard to non-overshoot characteristics are obtained.Finally,the performance boundaries of LADRC and PI control are explicitly compared with each other,which shows that the former is more superior in most cases.展开更多
Consensus problems of first-order multi-agent systems with multiple time delays are investigated in this paper. We discuss three cases： 1） continuous, 2） discrete, and 3） a continuous system with a proportional pl...Consensus problems of first-order multi-agent systems with multiple time delays are investigated in this paper. We discuss three cases： 1） continuous, 2） discrete, and 3） a continuous system with a proportional plus derivative controller. In each case, the system contains simultaneous communication and input time delays. Supposing a dynamic multi-agent system with directed topology that contains a globally reachable node, the sufficient convergence condition of the system is discussed with respect to each of the three cases based on the generalized Nyquist criterion and the frequency-domain analysis approach, yielding conclusions that are either less conservative than or agree with previously published results. We know that the convergence condition of the system depends mainly on each agent’s input time delay and the adjacent weights but is independent of the communication delay between agents, whether the system is continuous or discrete. Finally, simulation examples are given to verify the theoretical analysis.展开更多
文摘Methane generation in landfills and its inadequate management represent the major avoidable source of anthropogenic methane today. This paper models methane production and the potential resources expected (electrical energy production and potential carbon credits from avoided CH4 emissions) from its proper management in a municipal solid waste landfill located in Ouagadougou, Burkina Faso. The modeling was carried out using two first-order decay (FOD) models (LandGEM V3.02 and SWANA) using parameters evaluated on the basis of the characteristics of the waste admitted to the landfill and weather data for the site. At the same time, production data have been collected since 2016 in order to compare them with the model results. The results obtained from these models were compared to experimental one. For the simulation of methane production, the SWANA model showed better consistency with experimental data, with a coefficient of determination (R²) of 0.59 compared with the LandGEM model, which obtained a coefficient of 0.006. Thus, despite the low correlation values linked to the poor consistency of experimental data, the SWANA model models methane production much better than the LandGEM model. Thus, despite the low correlation values linked to the poor consistency of the experimental data, the SWANA model models methane production much better than the LandGEM V3.02 model. It was noted that the poor consistency of the experimental data justifies these low coefficients, and that they can be improved in the future thanks to ongoing in situ measurements. According to the SWANA model prediction, in 27 years of operation a biogas plant with 33% electrical efficiency using biogas from the Polesgo landfill would avoid 1,340 GgCO2e. Also, the evaluation of revenues due to electricity and carbon credit gave a total revenue derived from methane production of US$27.38 million at a cost of US$10.5/tonne CO2e.
文摘In this paper,we present a novel first-order digitalΣΔconverter tailored for digital-to-analog applications,focusing on achieving both high yield and reduced silicon estate.Our approach incorporates a substantial level of dithering noise into the input signal,strategically aimed at mitigating the spurious frequencies commonly encountered in such converters.Validation of our design is performed through simulations using a high-level simulator specialized in mixed-signal circuit analysis.The results underscore the enhanced performance of our circuit,especially in reducing spurious frequencies,highlighting its efficiency and effectiveness.The final circuit exhibits an effective number of bits of 13.
基金Supported by the National Natural Science Foundation of China (Grant Nos.52088102 and 51879287)National Key Research and Development Program of China (Grant No.2022YFB2602301)。
文摘Long-term responses of floating structures pose a great concern in their design phase. Existing approaches for addressing long-term extreme responses are extremely cumbersome for adoption. This work aims to develop an approach for the long-term extreme-response analysis of floating structures. A modified gradient-based retrieval algorithm in conjunction with the inverse first-order reliability method(IFORM) is proposed to enable the use of convolution models in long-term extreme analysis of structures with an analytical formula of response amplitude operator(RAO). The proposed algorithm ensures convergence stability and iteration accuracy and exhibits a higher computational efficiency than the traditional backtracking method. However, when the RAO of general offshore structures cannot be analytically expressed, the convolutional integration method fails to function properly. A numerical discretization approach is further proposed for offshore structures in the case when the analytical expression of the RAO is not feasible. Through iterative discretization of environmental contours(ECs) and RAOs, a detailed procedure is proposed to calculate the long-term response extremes of offshore structures. The validity and accuracy of the proposed approach are tested using a floating offshore wind turbine as a numerical example. The long-term extreme heave responses of various return periods are calculated via the IFORM in conjunction with a numerical discretization approach. The environmental data corresponding to N-year structural responses are located inside the ECs, which indicates that the selection of design points directly along the ECs yields conservative design results.
基金supported by the National Natural Science Foundation of China(Grant Nos.52109144,52025094 and 52222905).
文摘This paper introduces a novel approach for parameter sensitivity evaluation and efficient slope reliability analysis based on quantile-based first-order second-moment method(QFOSM).The core principles of the QFOSM are elucidated geometrically from the perspective of expanding ellipsoids.Based on this geometric interpretation,the QFOSM is further extended to estimate sensitivity indices and assess the significance of various uncertain parameters involved in the slope system.The proposed method has the advantage of computational simplicity,akin to the conventional first-order second-moment method(FOSM),while providing estimation accuracy close to that of the first-order reliability method(FORM).Its performance is demonstrated with a numerical example and three slope examples.The results show that the proposed method can efficiently estimate the slope reliability and simultaneously evaluate the sensitivity of the uncertain parameters.The proposed method does not involve complex optimization or iteration required by the FORM.It can provide a valuable complement to the existing approximate reliability analysis methods,offering rapid sensitivity evaluation and slope reliability analysis.
文摘Investigating natural-inspired applications is a perennially appealing subject for scientists. The current increase in the speed of natural-origin structure growth may be linked to their superior mechanical properties and environmental resilience. Biological composite structures with helicoidal schemes and designs have remarkable capacities to absorb impact energy and withstand damage. However, there is a dearth of extensive study on the influence of fiber redirection and reorientation inside the matrix of a helicoid structure on its mechanical performance and reactivity. The present study aimed to explore the static and transient responses of a bio-inspired helicoid laminated composite(B-iHLC) shell under the influence of an explosive load using an isomorphic method. The structural integrity of the shell is maintained by a viscoelastic basis known as the Pasternak foundation, which encompasses two coefficients of stiffness and one coefficient of damping. The equilibrium equations governing shell dynamics are obtained by using Hamilton's principle and including the modified first-order shear theory,therefore obviating the need to employ a shear correction factor. The paper's model and approach are validated by doing numerical comparisons with respected publications. The findings of this study may be used in the construction of military and civilian infrastructure in situations when the structure is subjected to severe stresses that might potentially result in catastrophic collapse. The findings of this paper serve as the foundation for several other issues, including geometric optimization and the dynamic response of similar mechanical structures.
文摘Using Euler’s first-order explicit(EE)method and the peridynamic differential operator(PDDO)to discretize the time and internal crystal-size derivatives,respectively,the Euler’s first-order explicit method–peridynamic differential operator(EE–PDDO)was obtained for solving the one-dimensional population balance equation in crystallization.Four different conditions during crystallization were studied:size-independent growth,sizedependent growth in a batch process,nucleation and size-independent growth,and nucleation and size-dependent growth in a continuous process.The high accuracy of the EE–PDDO method was confirmed by comparing it with the numerical results obtained using the second-order upwind and HR-van methods.The method is characterized by non-oscillation and high accuracy,especially in the discontinuous and sharp crystal size distribution.The stability of the EE–PDDO method,choice of weight function in the PDDO method,and optimal time step are also discussed.
基金supported by the National Natural Science Foundation of China (NSFC) under Grant Nos. 12375243 and 12388101the Strategic Priority Research Program of the Chinese Academy of Sciences under Grant Nos. XDA25050400, XDA25010200, and XDA25010100+1 种基金the Science Challenge Projectthe Fundamental Research Funds for the Central Universities。
文摘Two-plasmon-decay instability(TPD)poses a critical target preheating risk in direct-drive inertial confinement fusion.In this paper,TPD collectively driven by dual laser beams consisting of a normal-incidence laser beam(Beam-N)and a large-angle-incidence laser beam(Beam-L)is investigated via particle-in-cell simulations.It is found that significant TPD growth can develop in this regime at previously unexpected low laser intensities if the intensity of Beam-L exceeds the large-angle-incidence threshold.Both beams contribute to the growth of TPD in a“seed-amplification”manner in which the absolute instability driven by Beam-L provides the seeds that are convectively amplified by Beam-N,making TPD energetically important and causing significant pump depletion and hot-electron generation.
基金the supercomputing center of USTC for their strong supportsupported by the National Key R&D Program of China(Grant Nos.2023YFA1609400,2023YFA1606703,2020YFA0406400,and 2020YFA0406300)+3 种基金the International Partnership Program of the Chinese Academy of Sciences(Grant No.211134KYSB20200057)the National Natural Science Foundation of China(Grant Nos.12035013,12061131003,12122509,12105276,11625523,12405091,12235018,and 12435007)the CAS Youth Team Program(Grant No.YSBR-101)the Natural Science Foundation of Guangxi Province,China(Grant No.2025GXNSFBA069314)。
文摘Weak radiative hyperon decays represent a rich interplay between weak interactions and the internal structure of baryons,offering profound insights into Quantum Chromodynamics and weak interactions.Recent experimental observations,particularly from BESIII,have revealed deviations from theoretical predictions.These deviations could signal new physics or the need for refined theoretical models incorporating intermediate resonance effects.This review discusses recent theoretical advancements and key experimental findings,focusing on recent measurements from BESIII and their implications for strong interactions and baryon structure.
基金supported by the National Key Research and Development Project,China(No.2023YFA1606404)the Strategic Priority Research Program of Chinese Academy of Sciences(No.XDB34010300)+5 种基金the National Natural Science Foundation of China(Nos.12022501,12105329,12475127)the Guangdong Major Project of Basic and Applied Basic Research(No.2021B0301030006)the Research Program of Heavy Ion Science and Technology Key Laboratory,Institute of Modern Physics,Chinese Academy of Sciences(Nos.HIST2024KS04,HIST2024CO04)Longyuan Youth Innovation and Entrepreneurship Talent Project of Gansu Province(No.2024GZT04)State Key Laboratory of Nuclear Physics and Technology,Peking University(No.NPT2023KFY01)the Major Science and Technology Projects in Gansu Province(No.24GD13GA005)。
文摘A state-of-the-art detector array with a digital data acquisition system has been developed for charged-particle decay studies,includingβ-delayed protons,αdecay,and direct proton emissions from exotic proton-rich nuclei.The digital data acquisition system enables precise synchronization and processing of complex signals from various detectors,such as plastic scintillators,silicon detectors,and germaniumγdetectors.The system's performance was evaluated using theβdecay of^(32)Ar and its neighboring nuclei,produced via projectile fragmentation at the first Radioactive Ion Beam Line in Lanzhou(RIBLL1).Key measurements,including the half-life,charged-particle spectrum,andγ-ray spectrum,were obtained and compared with previous results for validation.Using the implantation–decay method,the isotopes of interest were implanted into two doublesided silicon strip detectors,where their subsequent decays were measured and correlated with preceding implantations using both position and time information.This detection system has potential for further applications,including the study ofβ-delayed charged-particle decay and direct proton emissions from even more exotic proton-rich nuclei.
文摘William Faulkner’s Southern Gothic style features fragmented narratives and rich symbolism that explore characters’psychological complexity and the decay of Southern society.In his seminal work exploring Emily Grierson’s tragic life,Faulkner employs a rich symbolic system that transcends mere literary decoration,instead functioning as a complex interpretative lens through which the disintegration of traditional Southern social structures can be understood.This paper argues that the symbolic framework in the narrative not only shapes Emily’s personal tragedy but also serves as a profound metaphorical representation of the collapse of the old Southern civilization-a system marked by rigid social hierarchies,racial tensions,and the slow erosion of aristocratic ideals in the face of inevitable social transformation.By dissecting the intricate symbolic elements-from the decaying mansion to the gothic imagery of death and preservation-this analysis reveals how Faulkner’s symbolic methodology becomes a nuanced historical and psychological commentary on the South’s traumatic transition from an antebellum past to a modernizing present.
基金financially supported by the National Natural Science Foundation of China(No.U2004210)Application Foundation Frontier Project of Wuhan Science and Technology Program(No.2020010601012199)City University of Hong Kong Strategic Research Grant,Hong Kong,China(No.7005505)。
文摘Vanadium nitride(VN)is a promising pseudocapacitive material due to the high theoretical capacity,rapid redox Faradaic kinetics,and appropriate potential window.Although VN shows large pseudocapacitance in alkaline electrolytes,the electrochemical instability and capacity degradation of VN electrode materials present significant challenges for practical applications.Herein,the capacitance decay mechanism of VN is investigated and a simple strategy to improve cycling stability of VN supercapacitor electrodes is proposed by introducing VO_(4)^(3-)anion in KOH electrolytes.Our results show that the VN electrode is electrochemical stabilization between-1.0and-0.4 V(vs.Hg/Hg O reference electrode)in 1.0 MKOH electrolyte,but demonstrates irreversible oxidation and fast capacitance decay in the potential range of-0.4 to0 V.In situ electrochemical measurements reveal that the capacitance decay of VN from-0.4 to 0 V is ascribed to the irreversible oxidation of vanadium(V)of N–V–O species by oxygen(O)of OH^(-).The as-generated oxidization species are subsequently dissolved into KOH electrolytes,thereby undermining the electrochemical stability of VN.However,this irreversible oxidation process could be hindered by introducing VO_(4)^(3-)in KOH electrolytes.A high volumetric specific capacitance of671.9 F.cm^(-3)(1 A.cm^(-3))and excellent cycling stability(120.3%over 1000 cycles)are achieved for VN nanorod electrode in KOH electrolytes containing VO_(4)^(3-).This study not only elucidates the failure mechanism of VN supercapacitor electrodes in alkaline electrolytes,but also provides new insights into enhancing pseudocapacitive energy storage of VN-based electrode materials.
基金supported by the National Natural Science Foundation of China(Nos.12375244 and 12135009)the Hunan Provincial Innovation Foundation for Postgraduate(Nos.CX20210007 and CX20230008)。
文摘In this study,we explore the impact of state-of-the-art laser fields on theαdecay half-life of deformed ground-state odd-A nuclei within the proton number range of 52–107.The calculations show that the presence of a laser field modulates theαdecay half-life by altering theαdecay penetration probability within a limited range.Moreover,the variance in the penetration probability rate of change between even–odd and odd–even nuclei is investigated.Furthermore,we investigate the rate of change of the penetration probability for the same parent nucleus with different neutron numbers,based on the characteristics of the odd-A nucleus.We found that the influence of the laser field on the penetration probability is determined by both the shell effect and odd–even staggering.This research contributes to the understanding of nuanced interactions between laser fields and nuclear decay processes.Therefore,valuable insights for future experiments in laser–nuclear physics are attainable using this study.
基金Supported by National Natural Science Foundation of China(31900271,32160086)Key Technology Research for Identification of Toxic Fungi in Guizhou Province(GKHZC[2020]1Y065)+1 种基金Guizhou Grassroots Science Popularization Action Plan Project([2025]04)Study on Carbon Storage and Carbon Sink Value of Forest Vegetation in State-owned Shatang Forest Farms in Guangxi(2021KY02).
文摘[Objectives] To investigate the species diversity of wood-decaying fungi in karst regions of southwest China. [Methods] The karst core regions of southwest China, specifically Guizhou, Guangxi, and Yunnan, were investigated for the first time to analyze the species diversity characteristics of wood-decaying fungi in this area. This analysis was conducted through a comprehensive 5-year field investigation and systematic identification process. [Results] The wood-decaying fungi exhibited a distinctive species composition and distribution pattern within karst habitats, encompassing significant groups such as Polyporaceae and Hymenochaetaceae. Furthermore, these fungi demonstrated varying functional characteristics across the two ecological types of standing tree decay and wood decay. It was observed that wood-decaying fungi had a significant impact on the material cycle within karst ecosystems by degrading lignin and cellulose. Furthermore, the distribution of species diversity was closely associated with the characteristics of karst geomorphology and the types of vegetation. [Conclusions] This study not only addresses the lack of background data regarding wood-decaying fungi resources in karst regions, but also elucidates the maintenance mechanisms of fragile ecosystems from the perspective of decomposers. It provides a scientific foundation for biodiversity conservation, the prevention and control of forest diseases, and sustainable ecological management in karst regions.
基金supported by the National Natural Science Foundation of China(Nos.12035011,11975167,12175151,12005139,11947123)the Guangdong Major Project of Basic and Applied Basic Research(No.2021B0301030006)the Steady Support Program for Higher Education Institutions of Shenzhen(Nos.20200810163629001,20200817005440001).
文摘The α-nucleus interaction is crucial in the description of α decay. Recently, we developed a pocket-type dynamical doublefolding potential(DDFP) that effectively incorporates both the surface-medium effect and interior Pauli repulsion in α decay [H. Zheng et al., Phys. Rev. C 109, L011301(2024)]. This potential results in a pocket geometry within the nuclear surface region, which is consistent with the α-clustering characteristics predicted by microscopic calculations. In this study, the accuracy of the pocket-type DDFP was validated via systematic calculations of α-decay half-lives and an extended evaluation of the nuclear charge radii of the daughter nuclei. The results demonstrate good agreement with the experimental data for both quantities, thereby confirming the reliability of the DDFP model. Compared with calculations that use α-nucleus interactions derived from conventional double-folding procedures, DDFP employs fewer adjustable parameters to achieve a more accurate description of the charge radii based on the experimental α-decay energies.
基金Supported by the National Natural Science Foundation of China (12271141)。
文摘Cauchy problem for the linearized bipolar isentropic Navier-Stokes-Poisson system in R^(2) is studied.Through the reformulation of unknown functions,we change the formal system into a linearized Navier-Stokes system and a unipolar Navier-Stokes-Poisson system.Based on a delicate analysis of the corresponding Green function,L^(2) decay estimate of the solution is obtained.
基金supported by the Anhui Provincial Natural Science Foundation(2408085QA031)the third author's work was supported by the National Natural Science Foundation of China(12001033).
文摘This paper studies the global existence and large-time behaviors of weak solutions to the kinetic particle model coupled with the incompressible Navier-Stokes equations in IR3.First,we obtain the global weak solution using the characteristic and energy methods.Then,under the small assumption of the mass of the particle,we show that the solutions decay at the algebraic time-decay rate.Finally,it is also proved that the above rate is optimal.It should be remarked that if the particle in the coupled system vanishes(i.e.f=O),our works coincide with the classical results by Schonbek[32](J Amer Math Soc,1991,4:423-449),which can be regarded as a generalization from a single fuid model to the two-phase fluid one.
基金supported by the Natural Science Research Project of Anhui Educational Committee(2023AH040155)Zhisu Liu's research was supported by the Guangdong Basic and Applied Basic Research Foundation(2023A1515011679+2 种基金2024A1515012704)the Fundamental Research Funds for the Central Universities,China University of Geosciences(Wuhan)(CUG2106211CUGST2).
文摘The paper is concerned with a class of elliptic equation with critical exponent and Dipole potential.More precisely,we make use of the refined Sobolev inequality with Morrey norm to obtain the existence and decay properties of nonnegative radial ground state solutions.
基金supported by the National Natural Science Foundation of China(Nos.12475136 and 12075327)。
文摘The potential of high-intensity lasers to influence nuclear decay processes has attracted considerable interest.This study quantitatively evaluated the effects of high-intensity lasers on α decay and cluster radioactivity.Our calculations revealed that,among the parent nuclei investigated,^(144)Nd is the most susceptible to laser-induced alterations,primarily because of its relatively low decay energy.Additionally,circularly polarized lasers exhibit a greater impact on decay modifications than linearly polarized lasers.Given the limited time resolution of current detectors,it is essential to account for the timeaveraging effect of the laser.By incorporating the effects of circular polarization,time averaging,and angular averaging,our theoretical predictions indicated that the modification of^(144)Nd decay could reach 0.1%at an intensity of 10^(27)W/cm^(2).However,this intensity significantly exceeds the current laser capability of 10^(23)W/cm^(2),and the predicted modification of 0.1%remains below the detection threshold of contemporary measurement techniques.Observing laser-assistedαdecay and^(14)C cluster radioactivity will likely remain unfeasible until both ultrahigh laser intensities and significant advancements in experimental resolution are achieved.
基金supported by the National Natural Science Foundation of China(60774088)the National High Technology Research and Development Program of China(863 Program)(2009AA04Z132)the Specialized Research Fund for the Doctoral Program of Higher Education of China(20090031110029)
文摘Conventional PI control encounters some problems when dealing with large lag process in the presence of parameter uncertainties.For the typical first-order process,an observerbased linear active disturbance rejection control（LADRC） scheme is presented to cope with the difficulties,and a reduced-order observer scheme is proposed further.Some quantitative dynamic results with regard to non-overshoot characteristics are obtained.Finally,the performance boundaries of LADRC and PI control are explicitly compared with each other,which shows that the former is more superior in most cases.
基金Project supported in part by the National Natural Science Foundation of China (Grant Nos. 60973114 and 61170249)in part by the Natural Science Foundation of CQCSTC (Grant Nos. 2009BA2024 and cstc2011jjA1320)in part by the State Key Laboratory of Power Transmission Equipment & System Securityand New Technology, Chongqing University (Grant No. 2007DA10512711206)
文摘Consensus problems of first-order multi-agent systems with multiple time delays are investigated in this paper. We discuss three cases： 1） continuous, 2） discrete, and 3） a continuous system with a proportional plus derivative controller. In each case, the system contains simultaneous communication and input time delays. Supposing a dynamic multi-agent system with directed topology that contains a globally reachable node, the sufficient convergence condition of the system is discussed with respect to each of the three cases based on the generalized Nyquist criterion and the frequency-domain analysis approach, yielding conclusions that are either less conservative than or agree with previously published results. We know that the convergence condition of the system depends mainly on each agent’s input time delay and the adjacent weights but is independent of the communication delay between agents, whether the system is continuous or discrete. Finally, simulation examples are given to verify the theoretical analysis.
