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A landscape persistence-based methodological framework for assessing ecological stability

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Environmental Science and Ecotechnology 2024年第1期17卷 31-39页

作者： Da lü Yihe lü Guangyao Gao Siqi Sun Yi Wang Bojie Fu State Key laboratory of Urban and Regional Ecology Research Center for Eco-Environmental SciencesChinese Academy of SciencesPO Box 2871Beijing100085China University of Chinese Academy of Sciences Beijing100049China

Ecological stability is a critical factor in global sustainable development,yet its significance has been *** we introduce a landscape-oriented framework to evaluate ecological stability in the Qingzang Plateau(QP).Our findings reveal a medium-high stability level in the QP,with minimal changes over recent *** driving factors vary across landscape types,with climate and anthropogenic factors emerging as crucial *** anthropogenic factors are strong but unstable due to policy changes and economic development,climatic factors exert a consistent *** on our results,we propose site-specific ecological conservation and restoration *** ecological stability assessment framework provides a practical tool to understand the link between environmental conditions and ecosystems.

关键词： Ecological stability assessment framework landscape changes Nature conservation and ecological restoration Nature-based solutions Qingzang Plateau

Optimal Control of Service Rates of Discrete-Time(s,Q)Queueing-Inventory Systems with Finite Buffer

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Journal of Systems Science and Systems Engineering 2024年第3期33卷 261-280页

作者： l.Iniya B.Sivakumar G.Arivarignan School of Mathematics Madurai Kamaraj UniversityMaduraiTamilnaduIndia Department of Statistics Manonmaniam Sundaranar UniversityTirunelveliTamilnaduIndia

This article,we develop an optimal policy to control the service rate of a discrete time queueing-inventory system with finite *** customers arrive according to a Bernoulli process and the service time for the customers are *** the buffer size attains its maximum,any arriving new customers are considered to be *** customers are served one by one according to FCFS rule and each customers request random number of *** inventory is replenished according to a(s,Q)inventory policy with geometric lead *** main objectives of this article are to determine the service rates to be employed at each slot so that the long run expected cost rate is minimized for fixed inventory level and fixed buffer size and to minimize the expected waiting time for a fixed inventory level and fixed buffer *** problems are modelled as Markov decision *** establish the existence of a stationary policy and employ linear programming method to find the optimal service *** provide some numerical examples to illustrate the behaviour of the model.

关键词： Queueing-inventory system discrete time batch demand-Markov decision process

Dual Additives for Stabilizing li Deposition and SEI Formation in Anode-Free li-Metal Batteries

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Energy & Environmental Materials 2024年第3期7卷 84-92页

作者： Baolin Wu Chunguang Chen Dmitri l.Danilov Zhiqiang Chen Ming Jiang Rüdiger-A.Eichel Peter H.l.Notten Forschungszentrum Jülich(IEK-9) D-52425Jülich Germany RWTH Aachen University D-52074Aachen Germany lNM Institute of MechanicsChinese Academy of SciencesBeijing 100190China School of Engineering Sciences University of Chinese Academy of SciencesBeijing 100049China Eindhoven University of Technology P.O.Box 5135600 MBEindhoven The Netherlands School of Electronics and Information Institute of Carbon Neutrality and New EnergyHangzhou Dianzi UniversityHangzhou 310018China University of Technology Sydney BroadwaySydney NSW 2007Australia

Anode-free li-metal batteries are of significant interest to energy storage industries due to their intrinsically high ***,the accumulative li dendrites and dead li continuously consume active li during *** results in a short lifetime and low Coulombic efficiency of anode-free li-metal *** effective electrolyte additives can improve the li deposition homogeneity and solid electrolyte interphase(SEI)stability for anode-free li-metal ***,we reveal that introducing dual additives,composed of liAsF6 and fluoroethylene carbonate,into a low-cost commercial carbonate electrolyte will boost the cycle life and average Coulombic efficiency of NMC‖Cu anode-free li-metal *** NMC‖Cu anode-free li-metal batteries with the dual additives exhibit a capacity retention of about 75%after 50 cycles,much higher than those with bare electrolytes(35%).The average Coulombic efficiency of the NMC‖Cu anode-free li-metal batteries with additives can maintain 98.3%over 100 *** contrast,the average Coulombic efficiency without additives rapidly decline to 97%after only 50 *** situ Raman measurements reveal that the prepared dual additives facilitate denser and smoother li morphology during li *** dual additives significantly suppress the li dendrite growth,enabling stable SEI formation on anode and cathode *** results provide a broad view of developing low-cost and high-effective functional electrolytes for high-energy and long-life anode-free li-metal batteries.

关键词： anode-free lithium metal battery dual additives in situ Raman li growth SEI formation

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Mechanics and physics under supergravity conditions

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Acta Mechanica Sinica 2024年第6期40卷 1-2页

作者： Chaofeng lü Chao Sun Shengqiang Cai Faculty of Mechanical Engineering and Mechanics Ningbo UniversityNingbo 315211China New Cornerstone Science laboratory Center for Combustion EnergyDepartment of Energy and Power EngineeringTsinghua UniversityBeijing 100084China Department of Mechanical and Aerospace Engineering University of CaliforniaSan DiegoLa Jolla CA 92093USA

"Supergravity"refers to the conditions where the effective gravity is greater than that of *** conditions are generally relevant to stellar evolution,geophysical movement,astrophysical flows,and *** also frequently occur in various engineering scenarios involving acceleration,such as the launch of space shuttles,operation of rotor engines,impacts and explosions,chemical separation processes,and overloaded testing *** is already demonstrated in physiological experiments that living organisms of animals or plants could be damaged,either temporarily or permanently,when subjected to *** create supergravity conditions for scientific research on the Earth,centrifugal equipment or rapidly rotating devices are omnipresent in various fields,such as aerospace engineering,geophysical science,chemical and biomedical engineering,nuclear engineering,rotating flows,and physical modeling tests.

关键词： geophysical Earth stellar

Investigation of the effects of radial clearance on the screw conveyor performances for different inclinations

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Particuology 2024年第9期92卷 72-80页

作者： Berna Bolat Birgül Aşçıoğlu Temiztaş Enes Sezer Department of Mechanical Engineering Yıldız Technical University34349BeşiktaşİstanbulTurkey

Screw conveyors are widely used for bulk material *** study investigates the critical role of radial clearance,the gap between the screw and the conveyor body,on performance across various inclination *** Discrete Element Method(DEM)is employed to analyze the effects of different radial clearances on conveyor performance for concrete aggregate and sand as bulk *** efficiencies and capacity losses serve as key performance indicators,quantitatively assessed for each radial clearance and inclination *** validation is conducted to corroborate the *** the study,the optimal radial clearance was identified as 1.5 to 3 times of the particle *** optimal clearance minimizes the material jamming and increases the performance for screw conveyors with different inclinations and bulk material types as a result.

关键词： Screw conveyors Radial clearance Discrete element method(DEM) Volumetric efficiency Conveyor performance

Science and reflections: With some thoughts to young applied scientists and engineers

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Earthquake Science 2024年第5期37卷 459-493页

作者： Robert l Nowack Department of Earth Atmospheric and Planetary SciencesPurdue UniversityWest LafayetteIN47906USA

I provide some science and reflections from my experiences working in geophysics,along with connections to computational and data sciences,including recent developments in machine learning.I highlight several individuals and groups who have influenced me,both through direct collaborations as well as from ideas and insights that I have learned *** my reflections are rooted in geophysics,they should also be relevant to other computational scientific and engineering fields.I also provide some thoughts for young,applied scientists and engineers.

关键词： geophysics computational and data science applied science and engineering

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Water quality, habitat, and fish assemblage relationships in middle-order agriculture and forest streams of the Mississippi Alluvial Plain

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Ecological Processes 2024年第1期13卷 217-236页

作者： Matthew l.Skoog Michael A.Eggleton Yushun Chen Department of Aquaculture and Fisheries University of Arkansas at Pine Bluff Minnesota Department of Natural Resources State Key laboratory of Freshwater Ecology and Biotechnology Institute of Hydrobiology Chinese Academy of Sciences University of Chinese Academy of Sciences

Background Agriculture has greatly influenced water quality, habitats, and fish assemblages in streams of the Mississippi Alluvial Plain(MAP) ecoregion. However, MAP streams have historically been understudied compared to streams in other agricultural regions of the USA. In this study, water quality, habitat, and fish assemblage composition were assessed seasonally(spring, summer, and fall) in eight representative MAP streams located across three U.S. states. The study design included four streams containing highly agricultural watersheds(herein termed “agriculture” streams) and four streams containing mostly forested watersheds(herein termed “forest” streams), which were intended to represent reference conditions for MAP *** In general, forest streams contained significantly better instream and riparian habitats than agriculture streams(P = 0.010–0.040) whereas agriculture streams contained significantly greater levels of primary nutrients(P lture and forest streams with respect to other physical and chemical variables were intermittent and season dependent. Fish assemblages in agriculture and forest streams were structured primarily along an environmental gradient reflecting instream habitat conditions, water nutrient concentrations, and benthic chlorophyll-a production. Structurally, fish assemblages in both stream types contained many regionally common species, though some species appeared to exhibit affinities for a particular stream type. Functionally, fish assemblages in agriculture streams contained more tolerant species, more omnivores, and fewer insectivores compared to forest stream assemblages, which were nearly all insectivores. Overall, one-third of the fish specimens collected in forest streams classified as intolerant *** Our results suggested that stream water quality, habitat, and fish assemblages differed between agriculture and forest streams in the MAP, with fish assemblages e

关键词： Agriculture Stream land use Water quality Habitat Fish Multivariate statistics Mississippi Alluvial Plain

Determination of the standardized ileal digestible calcium requirement of Ross broilers from hatch to day 14 post-hatch

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Animal Nutrition 2024年第1期16卷 122-129页

作者： Carrie l.Walk Raffaella Aureli Pauline Jenn DSM Nutritional Products Delves RoadHeanorDerbyshireDE757SGUnited Kingdom Research Center for Animal Nutrition and Health DSM Nutritional ProductsVillage-Neuf68128France

An experiment was conducted to determine the standardized ileal digestible(SID)calcium requirement of fast-growing broilers from hatch to d 14 *** 308(n=360)male broilers were obtained on day of hatch and allocated to 1 of 5 treatments in battery *** were 6 birds per cage and 12 pens per *** treatments were formulated to contain 0.60%,0.46%,0.32%or 0.18%SID *** final treatment was formulated using total Ca to meet or exceed all nutrient requirements,including 0.90%total Ca and 0.49%non-phytate P(nPP),using the same *** treatment was the reference diet for comparison and validation of the SID Ca *** and feed were weighed at placement and on d *** and ileal contents were obtained on d 14 and excreta was collected per pen and pooled on d *** were analyzed using JMP Pro and requirements were estimated using 3different non-linear regression *** the SID Ca content in the diet from 0.18%to 0.60%improved(quadratic,Plity corrected feed conversion ratio(mFCR).The estimated SID Ca requirement to optimize gain or m FCR was between 0.39%and 0.52%.Tibia ash percent and weight increased(quadratic,Plization was improved in birds fed diets formulated using SID Ca compared with birds fed the reference *** conclusion,the SID Ca requirement of fast-growing broilers from hatch to d 14 was estimated between 0.534%and 0.398%when quadratic,straight-broken line,or quadratic-broken line regressions were *** results agree with previously published data evaluating the SID Ca requirement of fast-growth broilers from hatch to d 10.

关键词： Apparent ileal digestibility Digestible calcium Requirements Retention Tibia ash

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Beyond network centrality: individual-level behavioral traits for predicting information superspreaders in social media

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National Science Review 2024年第7期11卷 148-157页

作者： Fang Zhou linyuan lü Jianguo liu Manuel Sebastian Mariani Institute of Fundamental and Frontier Sciences University of Electronic Science and Technology of China Yangtze Delta Region Institute(Huzhou) University of Electronic Science and Technology of China School of Cyber Science and Technology University of Science and Technology of China Department of Digital Economics Shanghai University of Finance and Economics URPP Social Networks Universit?t Zürich

Understanding the heterogeneous role of individuals in large-scale information spreading is essential to manage online behavior as well as its potential offline consequences. To this end, most existing studies from diverse research domains focus on the disproportionate role played by highly connected ‘hub’ ***, we demonstrate here that information superspreaders in online social media are best understood and predicted by simultaneously considering two individual-level behavioral traits: influence and susceptibility. Specifically, we derive a nonlinear network-based algorithm to quantify individuals' influence and susceptibility from multiple spreading event data. By applying the algorithm to large-scale data from Twitter and Weibo, we demonstrate that individuals' estimated influence and susceptibility scores enable predictions of future superspreaders above and beyond network centrality, and reveal new insights into the network positions of the superspreaders.

关键词： complex networks social networks social media information spreading superspreaders