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Effects of microplastic polystyrene,simulated acid rain and arbuscular mycorrhizal fungi on Trifolium repens growth and soil microbial community composition

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Pedosphere 2024年第2期34卷 424-437页

作者： Wanlin li Yan xiao College of Agro-grassland Science Nanjing Agricultural UniversityNanjing 210095China

Microplastic pollution is a global and ubiquitous environmental problem in the oceans as well as in the terrestrial *** examined the fate of microplastic polystyrene(MPS)beads in experimental soil in the presence and absence of symbiotic arbuscular mycorrhizal fungi(AMF)and simulated acid rain(SAR)to determine whether the combinations of these three factors altered the growth of white clover Trifolium *** found that MPS,SAR,or AMF added singly to soil did not alter *** growth or *** contrast,MPS and AMF together significantly reduced shoot biomass,while SAR and MPS together significantly reduced soil available phosphorus independent of AMF *** polystyrene,AMF,and SAR together significantly reduced soil NO_(3)^(-)-*** mycorrhizal fungi added singly also enriched the beneficial soil bacteria(genus Solirubrobacter),while MPS combined with AMF significantly enriched the potential plant pathogenic fungus *** mycorrhizal fungi inoculation with MPS increased the abundance of soil hydrocarbon degraders independent of the presence of *** addition,the abundance of soil nitrate reducers was increased by MPS,especially in the presence of AMF and ***,SAR alone increased the abundance of soil pathogens within the fungal community including antibiotic *** findings indicate that the coexistence of MPS,SAR,and AMF may exacerbate the adverse effects of MPS on soil and plant health.

关键词： acid deposition arbuscular mycorrhizal fungi symbiosis hydrocarbon degradation microbial alpha diversity microplastic pollution pathogen

Higher-order expansions of powered extremes of logarithmic general error distribution

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Applied Mathematics(A Journal of Chinese Universities) 2024年第1期39卷 47-54页

作者： TAN xiao-feng li li-hui School of Mathematics and Statistics Southwest UniversityChongqing 400715China

In this paper,Let M_(n)denote the maximum of logarithmic general error distribution with parameter v≥***-order expansions for distributions of powered extremes M_(n)^(p)are derived under an optimal choice of normalizing *** is shown that M_(n)^(p),when v=1,converges to the Frechet extreme value distribution at the rate of 1/n,and if v>1 then M_(n)^(p)converges to the Gumbel extreme value distribution at the rate of(loglogn)^(2)=(log n)^(1-1/v).

关键词： logarithmic general error distribution convergence rate higher-order expansion powered ex-treme

Analysis of Piezoelectric Semiconductor Structures Considering Both Physical and Geometric Nonlinearities

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Acta Mechanica Solida Sinica 2024年第1期37卷 72-81页

作者： Zhengguang xiao Shuangpeng li Chunli Zhang Key Laboratory of Soft Machines and Smart Devices of Zhejiang Province Department of Engineering MechanicsZhejiang UniversityHangzhou 310027China Huanjiang Laboratory Zhuji 311816China

Piezoelectric semiconductors(PSs),such as ZnO and GaN,known as the third-generation semiconductors,have promising applications in electronic and optoelectronic devices due to the coexistence and interaction of piezoelectricity and semiconductor *** modeling of PS structures under external loads,such as thermal and mechanical loads,plays a crucial role in the design of PS *** this work,we propose a nonlinear fully coupling theoretical model and investigate the multi-field coupling behaviors of PS structures and PN junctions under thermal and mechanical loads,considering physical and geometric *** electromechanical and semiconducting behaviors of a PS rod-like structure with flexural deformations under different combinations of temperature changes and mechanical loads are *** tuning effect of temperature changes and mechanical loads on multi-field coupling behaviors of PSs is *** current–voltage characteristics of PS PN junctions are studied under different combinations of temperature changes and mechanical *** obtained results are helpful for the development of novel PS devices.

关键词： Piezoelectric semiconductor Nonlinearity Multi-field Coupling Tuning

A Fluctuation Test for Structural Change Detection in Heterogeneous Panel Data Models

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Journal of Systems Science & Complexity 2024年第3期37卷 1184-1208页

作者： li Fuxiao xiao Yanting CHEN Zhanshou Department of Applied Mathematics Xi'an University of TechnologyXi'an 710048China School of Mathematics and Statistics Qinghai Normal UniversityXining 810008China Academy of Plateau Science and Sustainability Xining 810008China

Structural change in panel data is a widespread phenomena. This paper proposes a fluctuation test to detect a structural change at an unknown date in heterogeneous panel data models with or without common correlated effects. The asymptotic properties of the fluctuation statistics in two cases are developed under the null and local alternative hypothesis. Furthermore, the consistency of the change point estimator is proven. Monte Carlo simulation shows that the fluctuation test can control the probability of type I error in most cases, and the empirical power is high in case of small and moderate sample sizes. An application of the procedure to a real data is presented.

关键词： Common correlated effects fuctuation test heterogeneous panel data models structural change detection

Proposing a development framework for sustainable architecture, engineering, and construction industry in China: Challenges, best practice, and future directions

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Frontiers of Structural and Civil Engineering 2024年第5期18卷 805-814页

作者： Peixian li Yujie LU Xuwen xiao College of Architecture and Urban Planning Tongji UniversityShanghai 200092China Key Laboratory of Ecology and Energy Saving Study of Dense Habitat(Tongji University) Ministry of EducationShanghai 200092China College of Civil Engineering Tongji UniversityShanghai 200092China Key Laboratory of Performance Evolution and Control for Engineering Structures of Ministry of Education Tongji UniversityShanghai 200092China China State Construction Engineering Corporation Beijing 100029China

China’s architecture,engineering,and construction(AEC)industry needs a clear and sustainable development *** inspiration from speeches delivered at a seminar hosted by the Chinese Academy of Engineering and extensive literature research on Chinese policies,this article presents a summary of the current trends in the AEC industry in four dimensions:industrialization as the foundation,intelligence as the enabler,lean management as the strategy,and green development as the *** four dimensions are intricately interconnected and rooted in multiple *** article provides a detailed review of the current practices,challenges,and future directions associated with each ***,ten grand challenges were proposed to stimulate discussions on the future of the AEC *** article offers an overarching understanding of the AEC industry and presents a four-dimension framework for sustainable development,which can be valuable for AEC practitioners.

关键词： green building lean construction prefabrication smart construction sustainable development

Effects of Different light Qualities on the Growth Characteristics of Populus trinervis

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Phyton-International Journal of Experimental Botany 2024年第5期93卷 1043-1056页

作者： Jiaqi li Zhensheng Qiao Dan zong Chengzhong He Key Laboratory for Forest Genetics and Tree Improvement and Propagation in Universities of Yunnan Province Southwest Forestry UniversityKunmingChina Key Laboratory of Biodiversity Conservation in Southwest China State Forestry AdministrationSouthwest Forestry UniversityKunmingChina Key Laboratory for Forestry Resources Conservation and Utilization in the Southwest Mountains of China Ministry of EducationSouthwest Forestry UniversityKunmingChina

Populus trinervis is native to China and plays an irreplaceable role in maintaining the ecological balance of boreal and temperate *** mainly grows in high-altitude *** present,there are limited studies on the response of *** to different light qualities,so it is necessary to investigate the photosynthetic physiological changes of *** in different light *** our study,*** was grown for 8 months under light filtered by three different colored *** three treatments were blue film,green film,and white plastic *** effects of blue(B),green(G),and white(W)light on photosynthetic pigment content,absolute growth,photosynthetic parameters,soluble sugar content,and chlorophyll fluorescence parameters were studied,*** to the Wtreatment,the chlorophyll a and b,carotenoids,total chlorophyll content(a+b),absolute growth of seedling height,net photosynthetic rate(PN),water use efficiency(WUE),total soluble sugars,sucrose,and nonphotochemical quenching(NPQ)of *** were significantly increased under B ***,chlorophyll a and b,carotenoids,total chlorophyll(a+b),transpiration rate(Tr),intercellular CO_(2) concentration(Ci),stomatal conductance(gs),absolute growth of seedling height and leaf length,reducing sugar,total soluble sugar content,and NPQ were significantly increased under G *** results showed that the absolute growth and chlorophyll content of *** were increased under B light,while the sugar and photosynthetic parameters were increased under G *** studies may look into how B light impacts absolute growth and promotional mechanisms,as well as how G light affects the accumulation of sugar levels.

关键词： Blue light green light white light photosynthetic pigment soluble sugar

Phenomenology of heavy neutral gauge boson at muon collider

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Science China(Physics,Mechanics & Astronomy) 2024年第3期67卷 60-79页

作者： zongyang Lu Honglei li Zhi-Long Han zong-Guo Si liuxin Zhao School of Physics and Technology University of JinanJinan 250022China School of Physics Shandong UniversityJinan 250100China

Heavy neutral gauge boson Z' is proposed in many new physics *** has rich phenomena at the future muon *** study the properties of Z' boson with the process of μ^(+)μ^(-)→qq,μ^(+)μ^(-)→l^(+)l^(-),μ^(+)μ^(-)→ ZH and μ^(+)μ^(-)→ W^(+)W^(-).The discrepancy of Z' coupling to different types of particles can be shown in the cross section distributions around the resonance peak of various decay *** distributions of the final quark or lepton in μ^(+)μ^(-)→qq/l^(+)l^(-)process are sensitive to the parameters such as mass of Z' and the Z-Z' mixing *** interaction of new gauge boson coupling to the standard model gauge particles and Higgs boson are also studied through μ^(+)μ^(-)→ ZH→l^(+)l^(-)bb and μ^(+)u^(-)→ W^(+)W^(-)→l^(+)l^(-)v_(l)v_(l).The cross section and the final particles' angular distributions with the contribution of Z' boson differ from those processes with only standard model particles.A forward-backward asymmetry defined by the angular distribution is provided to show the potential of searching for new physics at the muon ***,the beam polarization with certain value can effectively enlarge the forward-backward asymmetry.

关键词： Z′boson muon collider new physics

Crashworthiness Design and Multi-Objective Optimization of Bionic Thin-Walled Hybrid Tube Structures

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Computer Modeling in Engineering & Sciences 2024年第4期139卷 999-1016页

作者： Pingfan li Jiumei xiao Department of Applied Mechanics University of Sciences and Technology BeijingBeijing100083China

Thin-walled structures are widely used in cars due to their lightweight construction and energy-absorbing ***,issues such as high initial stress and lowenergy-absorbing efficiency *** study proposes a novel energy-absorbing structure inwhich a straight tube is combinedwith a conical tube and a bamboo-inspired bulkhead structure is *** configuration allows the conical tube to flip outward first and then fold together with the straight *** deformation mode absorbs more energy and less peak force than the conical tube sinking and flipping *** finite element numerical simulation,the specific energy absorption capacity of the structure is increased by 26%compared to that of a regular circular cross-section ***,the impact resistance of the bionic straight tapered tube structure is further improved through multi-objective optimization,promoting the engineering application and lightweight design of hybrid cross-section tubes.

关键词： Crashworthiness tube inversion multi-objective optimization energy absorption

Navigation Finsler metrics on a gradient Ricci soliton

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Applied Mathematics(A Journal of Chinese Universities) 2024年第2期39卷 266-275页

作者： li Ying MO xiao-huan WANG xiao-yang Department of Applied Mathematics Zhejiang University of TechnologyHangzhou 310023China Key Laboratory of Pure and Applied Mathematics School of Mathematical SciencesPeking UniversityBeijing 100871China School of Mathematics and Statistics Beijing Institute of TechnologyBeijing 100081China

In this paper,we study a class of Finsler metrics defined by a vector field on a gradient Ricci *** obtain a necessary and sufficient condition for these Finsler metrics on a compact gradient Ricci soliton to be of isotropic S-curvature by establishing a new integral *** we determine the Ricci curvature of navigation Finsler metrics of isotropic S-curvature on a gradient Ricci soliton generalizing result only known in the case when such soliton is of Einstein *** its application,we obtain the Ricci curvature of all navigation Finsler metrics of isotropic S-curvature on Gaussian shrinking soliton.

关键词： gradient Ricci soliton navigation Finsler metric isotropic S-curvature Ricci curvature Gaussian shrinking soliton