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秸秆分拨引导式玉米免耕防堵机构设计与试验

农业机械学报 2019年第8期50卷 52-58页

作者：牛萌萌方会敏 chandio f a 史嵩薛艳芳刘虎山东省农业机械科学研究院济南250100 信德农业大学农业工程学院坦杜阿拉亚70060 山东省农业科学院玉米研究所济南250100

为解决免耕播种机麦茬地作业的拥堵问题,在拨抛式防堵装置的基础上提出秸秆分拨引导的防堵设计思路,设计了阿基米德螺线型防堵机构。该装置可引导秸秆攀升,实现层叠堆积,缓解秸秆平行拨离苗带时造成的秸秆局部集中,从而实现有效防堵。... 详细信息

为解决免耕播种机麦茬地作业的拥堵问题,在拨抛式防堵装置的基础上提出秸秆分拨引导的防堵设计思路,设计了阿基米德螺线型防堵机构。该装置可引导秸秆攀升,实现层叠堆积,缓解秸秆平行拨离苗带时造成的秸秆局部集中,从而实现有效防堵。运用离散元分析软件EDEM 2.7,建立了秸秆土壤防堵机构相互作用的仿真模型,分别对单个目标秸秆和秸秆群体进行运动追踪,验证了分拨引导和层叠堆积理念。对试验样机进行了田间性能试验和作业参数优选试验,结果表明:在播种过程中,阿基米德螺线型防堵机构作业顺畅,未发生中、重度堵塞及晾籽;防堵机构最佳工作参数为前进速度7 km/h、转速600 r/min,此时秸秆清除率最高,为92.6%。本文设计的防堵机构性能优于前期课题组设计的防堵机构和某商品化防堵机构。

关键词：玉米免耕播种机防堵机构分拨引导阿基米德螺线

Carbon compensation and carbon neutrality:Regional variations based on net carbon transfer of trade in China

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Geoscience frontiers 2024年第4期15卷 159-175页

作者： Xue Han Xincai Gao fayyaz Ahmad Abbas Ali chandio Salim Khan School of Economics Lanzhou UniversityLanzhou 730000GansuChina College of Economics Sichuan Agricultural UniversityChengdu 611130China School of Management Guangzhou UniversityGuangzhou 510006China

Inter-provincial carbon compensation is an important means for a country to realize regional environmental protection and achieve coordinated regional development and realize the carbon neutral *** is easier to realize inter-provincial carbon compensation compared with the national *** on the multi-regional input-output model and the input-output data of 30 provinces in China,this study measured the carbon transfer in,carbon transfer out and net carbon transfer of each province,and based on the undesirable slacks-based measurement model under the common frontier,the provinces were given the shadow price of carbon emission in line with the situation of the local economic development,resource endowment,and industrial structure,and based on which,the amount of carbon compensation of each province was *** results show that:China's provinces and regions have a larger share of trade-implied carbon emissions;the net carbon transfer in areas mainly concentrated in the traditional energy provinces,which provide industrial products for other regions and undertake the transfer of carbon emissions,and become the main carbon compensation recipient areas;the net carbon transfer out is mainly concentrated in the economically developed and densely populated areas such as Beijing-Tianjin region and the eastern and southern coasts,which satisfy the end-consumption by purchasing a large number of industrial products and generate a large amount of carbon *** out;becoming the main carbon offset payment *** on the results of this study,it is proposed to improve the national provincial carbon offset mechanism and implement a differentiated and synergistic carbon emission reduction cooperation *** research program of this study can provide a reference for the development of inter-regional carbon offset programs.

关键词： Carbon transfer Shadow price Carbon emission responsibility Carbon compensation

Thermodynamic Performance Analysis of Geothermal Power Plant Based on Organic Rankine Cycle (ORC) Using Mixture of Pure Working fluids

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Energy Engineering 2024年第8期121卷 2023-2038页

作者： Abdul Sattar Laghari Mohammad Waqas chandio Laveet Kumar Mamdouh El Haj Assad Department of Mechanical Engineering Mehran University of Engineering and TechnologyJamshoro76062Pakistan Department of Mechanical and Industrial Engineering College of EngineeringQatar UniversityDoha00000Qatar Sustainable&Renewable Energy Engineering Department University of SharjahSharjah00000United Arab Emirates

The selection of working fluid significantly impacts the geothermal ORC’s *** a mixture as a working fluid is a strategy to improve the output of geothermal *** the current study,modelling and thermodynamic analysis of ORC,using geothermal as a heat source,is carried out at fixed operating *** model is simulated in the Engineering Equation Solver(EES).An environment-friendly mixture of fluids,i.e.,R245fa/R600a,with a suitable mole fraction,is used as the operating *** mixture provided the most convenient results compared to the pure working fluid under fixed operating *** impact of varying the evaporator pressure on the performance parameters,including energy efficiency,exergy efficiency and net power output is *** system provided the optimal performance once the evaporator pressure reached the maximum *** efficiencies:Energy and Exergy,and Net Power output of the system are 16.62%,64.08%and 2199 kW for the basic cycle and 20.72%,67.76%and 2326 kW respectively for the regenerative cycle.

关键词： Organic rankine cycle internal heat exchanger moderate-temperature geothermal source mixture of the fluid exergy

Control and vibration analyses of a sandwich doubly curved micro-composite shell with honeycomb,truss,and corrugated cores based on the fourth-order shear deformation theory

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Applied Mathematics and Mechanics(English Edition) 2024年第10期45卷 1773-1790页

作者： f.SHIRDELAN M.MOHAMMADIMEHR f.BARGOZINI Department of Solid Mechanics Faculty of Mechanical EngineeringUniversity of KashanKashan 87317-53153Iran

Curved shells are increasingly utilized in applied engineering due to their shared characteristics with other sandwich structures,flexibility,and attractive ***,the inability of controlling and regulating vibrations and destroying them afterward is a challenge to *** this paper,the curve shell equations and a linear quadratic regulator are adopted for the state feedback design to manage the structure vibrations in state space forms.A five-layer sandwich doubly curved micro-composite shell,comprising two piezoelectric layers for the sensor and actuator,is modeled by the fourth-order shear deformation *** core(honeycomb,truss,and corrugated)is analyzed for the bearing of transverse shear *** results show that the honeycomb core has a greater effect on the *** the parameters related to the core and the weight percentage of graphene increase,the frequency *** uniform distribution of graphene platelets results in the lowest natural frequency while the natural frequency ***,without taking into account the piezoelectric layers,the third-order shear deformation theory(TSDT)and fourth-order shear deformation theory(fOSDT)align ***,when the piezoelectric layers are incorporated,these two theories diverge significantly,with the frequencies in the fOSDT being lower than those in the TSDT.

关键词： vibration and control doubly curved shell micro-composite honeycomb truss corrugate core

Bolstering integrity in environmental data science and machine learning requires understanding socioecological inequity

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frontiers of Environmental Science & Engineering 2024年第5期18卷 171-179页

作者： Joe f.Bozeman III School of Civil and Environmental Engineering Georgia Institute of TechnologyAtlantaGA30332USA School of Public Policy Georgia Institute of TechnologyAtlantaGA30332USA

Socioecological inequity in environmental data science—such as inequities deriving from data-driven approaches and machine learning(ML)—are current issues subject to debate and *** is growing consensus around embedding equity throughout all research and design domains—from inception to administration,while also addressing procedural,distributive,and recognitional ***,practically doing so may seem onerous or daunting to *** current perspective helps to alleviate these types of concerns by providing substantiation for the connection between environmental data science and socioecological inequity,using the Systemic Equity framework,and provides the foundation for a paradigmatic shift toward normalizing the use of equity-centered approaches in environmental data science and ML *** the integrity of environmental data science and ML is just beginning from an equity-centered tool development and rigorous application *** this end,this perspective also provides relevant future directions and challenges by overviewing some meaningful tools and strategies—such as applying the Wells-Du Bois Protocol,employing fairness metrics,and systematically addressing irreproducibility;emerging needs and proposals—such as addressing data-proxy bias and supporting convergence research;and establishes a ten-step path ***,the work that environmental scientists and engineers do ultimately affect the well-being of us all.

关键词： Equity Bias Machine Learning Data Science Justice Systemic Equity

Premature axon-oligodendrocyte interaction contributes to stalling of experimental axon regeneration after injury to the white matter

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Neural Regeneration Research 2024年第3期19卷 469-470页

作者： Ephraim f.Trakhtenberg Department of Neuroscience University of Connecticut School of MedicineFarmingtonCTUSA

Studies from nearly 3 decades ago suggested that,in the central nervous system(CNS),myelination of axons by oligodendrocytes not only helps improve axonal conductivity but also stabilizes circuitry(Colello and Schwab,1994).Over the years,myelin sheaths produced by oligodendrocytes have been found to contain multiple molecules that are inhibitory to axonal growth(e.g.,MAG,NogoA,OMgp,Semaphorins)(Yiu and He,2006;Silver et al.,2014).After white matter injury in the adult CNS,myelin debris from damaged axons and dead oligodendrocytes accumulates in the forming glial scar and exposes these myelin-associated axon growth-inhibitory molecules to the injured axonal stumps,thereby contributing to the inhibition of axonal *** development,CNS axons reach their postsynaptic targets and stop growing before oligodendrocytes appear and myelinate them(foran and Peterson,1992;Dangata et al.,1996).Therefore,myelin-associated axon growth-inhibitory molecules interacting with already grown axons during myelination were thought to block axons from promiscuous sprouting and miswiring,thereby stabilizing neural circuitry in the CNS(Colello and Schwab,1994).

关键词： thereby white injury

An unexpected cellular fountain of youth:platelets provide factors rejuvenating brain functions

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Signal Transduction and Targeted Therapy 2024年第1期9卷 16-18页

作者： Harald f.Langer Department of Cardiology AngiologyHaemostaseology and Medical Intensive CareUniversity Medical Centre MannheimMedical Faculty MannheimHeidelberg UniversityMannheimGermany German Centre for Cardiovascular Research(DZHK) Partner Site Heidelberg/MannheimMannheimGermany European Center for Angioscience Medical Faculty MannheimHeidelberg UniversityMannheimGermany Cardiovascular systems biology Medical Clinic IUniversity Heart Center LübeckLübeckGermany

In a recent manuscript published in Nature,Schroer et *** that platelets and in particular platelet derived Pf-4(CXCL4)are a novel factor,which can rejuvenate the mammalian neuronal system.1 These findings have the potential to trigger an entire new field of research opening new platelet-derived candidate effector molecules for supporting regeneration.

关键词： supporting platelets finding

The viscous strip approach to simplify the calculation of the surface acoustic wave generated streaming

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Applied Mathematics and Mechanics(English Edition) 2024年第4期45卷 711-724页

作者： f.JAZINI DORCHEH M.GHASSEMI fuel Cells and Nano Systems(fCNS)Laboratory Department of Mechanical EngineeringK.N.Toosi University of TechnologyTehran 19697Iran

In recent decades,the importance of surface acoustic waves,as a biocompatible tool to integrate with microfluidics,has been proven in various medical and biological *** numerical modeling of acoustic streaming caused by surface acoustic waves in microchannels requires the effect of viscosity to be considered in the equations which complicates the *** this paper,it is shown that the major contribution of viscosity and the horizontal component of actuation is concentrated in a narrow region alongside the actuation *** the inviscid equations are considerably easier to solve,a division into the viscous and inviscid domains would alleviate the computational load *** particles'traces calculated by this approximation are excellently alongside their counterparts from the completely viscous *** is also shown that the optimum thickness for the viscous strip is about 9-fold the acoustic boundary layer thickness for various flow patterns and amplitudes of actuation.

关键词： surface acoustic wave microfluidics numerical simulation particle tracing acoustic streaming

Antimicrobial,antibiofilm,angiogenesis,anti-inflammatory,and wound healing activities of zinc nanoparticles green synthesized using ferula macrecolea extract

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Asian Pacific Journal of Tropical Biomedicine 2024年第6期14卷 259-268页

作者： Sultan f.Alnomasy Department of Medical Laboratories Sciences College of Applied Medical SciencesShaqra UniversityAl-Quwayiyah 19257Saudi Arabia

Objective:To assess the antimicrobial,antibiofilm,anti-inflammatory,angiogenic,and wound healing activities of zinc nanoparticles(ZNPs)green synthesized using ferula macrecolea ***:The green synthesis was conducted using the precipitation ***,the minimum inhibitory concentration(MIC),minimum bactericidal concentration(MBC),and minimum biofilm inhibition concentration 50%(MBIC50)of ZNPs against Staphylococcus aureus(***)and Pseudomonas aeruginosa(***)were *** effects of ZNPs on the gene expressions of Staphylococcus spp.[intracellular adhesion A(icaA)and D(icaD)]and ***(rhlI and rhlR)were investigated using quantitative real-time *** addition,the effects of ZNPs on wound healing,angiogenesis,and anti-inflammatory markers were ***:The green-synthesized ZNPs demonstrated significant antimicrobial efficacy against *** and *** biofilm formation in *** and *** was also inhibited by ZNPs with MBIC50 values of 3.30μg/mL and 2.08μg/mL,***,ZNPs downregulated the expression of biofilm-related genes icaA,icaD,rhlI,and rhlR in the tested *** also demonstrated promising in vitro wound healing effects by promoting fibroblast cell proliferation and wound closure in a dose-dependent manner.A significant increase in the expression of HLA-G5 and VEGf-A genes as well as a marked decrease in the expression of Nf-κB,IL-1β,and TNf-αgenes were observed in cells treated with ZNPs compared to the control group(Pffects against *** and *** and wound-healing effects by inhibiting biofilm formation,inducing angiogenesis,and reducing ***,further studies must be conducted to specify the accurate mechanisms of action and toxicity of ZNPs.

关键词： Wound healing Antibacterial Angiogenesis Nanomedicine ferula macrecolea Inflammation