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国外金属矿选矿 1984年第3期 27-33页

作者： E.C.Teoh f.lawson K N Han 朱玉霜澳大利亚维多利亚克莱顿蒙纳奇大学化学工程系

已合成2,3—烷二酮二肟并有作捕收剂,研究含镍硫化矿和氧化矿的浮选行为,此试验的物质是镍黄铁矿和镍红土矿,发现这些新捕收剂对含镍矿物很有选择性,对于硫化矿物,其效果与黄药捕收剂一样,浮选镍红土矿时稍可提高精矿品位。

关键词：捕收剂红土镍矿浮选药剂镍矿物金属矿物硫化矿镍回收率硫化镍矿表面活性剂水泥外加剂镍黄铁矿特效矿物表面浮选试验二酮精矿品位二肟

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粗铅连续加硫除铜

中国有色冶金 1980年第6期 22-27页

作者： f.lawson R.G.Kelly D.H.Ward 胡丕成

在一个叫做熔析除铜或“热析”除铜的作业中,使鼓风炉生产的粗铅冷却到接近其凝固点的温度时,铅中含铜一般为0.02～0.06%。铜的脱除常常是在一个称之为加硫除铜的间歇式作业中进行。在凝固点附近的温度下,将硫拌入铅液中,並用人工把浮... 详细信息

在一个叫做熔析除铜或“热析”除铜的作业中,使鼓风炉生产的粗铅冷却到接近其凝固点的温度时,铅中含铜一般为0.02～0.06%。铜的脱除常常是在一个称之为加硫除铜的间歇式作业中进行。在凝固点附近的温度下,将硫拌入铅液中,並用人工把浮到铅液上面的铜浮渣和铅的硫化物撇除。在拌入元素硫的粗铅中,残存铜的行为与某些受动力学支配的反应的出现是相一致的。这些反应决定了在过程中的某一特定时间内铜的存在形式。根据这些动力学原理,导致並研制出一种半工业性试验的连续加硫脱铜装置,其规模为0.5吨/时,一个工业规模的能力为36吨/时的连续加硫脱铜的设计现已准备就绪。已经研究出来的加硫除铜的数学模型能够准确地予测间歇作业及连续作业所能达到的效果。

关键词：粗铅鼓风炉元素硫硫肥加硫除铜除铜脱铜

Development of a Proof-of-Concept Multi-Method Computer Simulation to Support Rural Healthcare Disaster Preparedness Planning

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International Journal of Disaster Risk Science 2024年第3期15卷 346-358页

作者： Thomas A.Berg Kristina W.Kintziger Julie Suzuki Crumly Scott A.lawson Carole R.Myers Tracey T.Stansberry College of Nursing University of Tennessee Knoxville Department of Environmental Agricultural and Occupational Health University of Nebraska Medical Center Public Health and Healthcare Oak Ridge Associated Universities

Due to a lack of resources, rural communities often face challenges when planning catastrophic events. This project involved applying systems thinking and model-based systems engineering to develop a proof-of-concept, multi-method computer simulation and then determining whether the simulation could be used to assess the efficacy of disaster planning approaches on health outcomes in rural communities, as a function of primary healthcare. The project focus was a rural or non-urban healthcare system experiencing a natural hazard. Both system dynamics and discrete event models were incorporated to represent subsystem operations, crucial disaster responses, as well as three key response systems: public health, emergency management, and healthcare. The subsystem models included several components: policies/procedures, communications,resources, exercises/drills/training, healthcare space and staff, and the flow of affected people into and through the *** combined simulation can serve as a first step to a more comprehensive approach to helping rural communities achieve more efficient and effective healthcare planning for disaster responses.

关键词： Computer simulation Disaster preparedness Model-based systems engineering Rural healthcare System dynamics model Systems thinking

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 Engineering University of Kashan

Curved shells are increasingly utilized in applied engineering due to their shared characteristics with other sandwich structures, flexibility, and attractive appearance. However, the inability of controlling and regulating vibrations and destroying them afterward is a challenge to scientists. In 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 theory. The core(honeycomb, truss, and corrugated) is analyzed for the bearing of transverse shear forces. The results show that the honeycomb core has a greater effect on the vibrations. When the parameters related to the core and the weight percentage of graphene increase, the frequency increases. The uniform distribution of graphene platelets results in the lowest natural frequency while the natural frequency increases. furthermore, without taking into account the piezoelectric layers,the third-order shear deformation theory(TSDT) and fourth-order shear deformation theory(fOSDT) align closely. However, 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： 74f15 corrugate core doubly curved shell honeycomb micro-composite O343 truss vibration and control

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Impact of COVID-19 on Safety Performance for Motorcycles: Pre-and during-Pandemic Conditions

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Journal of Transportation Technologies 2024年第3期14卷 390-401页

作者： Hongyun Chen Amelia lawson Charles Hurda Madalyn Smith Tate Grant Civil Engineering Department Embry-Riddle Aeronautical University Daytona Beach FL USA

florida has the highest number of motorcycle fatalities in the United States and contains the second largest population of registered motorcycles. The COVID-19 pandemic influenced the roads, traffic, and driving behavior in the continental United States. Motorcycle crashes decreased during the COVID-19 years (2020 and 2021) while the fatality rates increased. The purpose of this study is to 1) investigate motorcycle crashes before and during the Pandemic period to understand the impacts on motorcycle safety and contributing factors to the crash severity levels;2) develop the crash predictive model for different degrees of severity in motorcycle crashes in florida. florida statewide crash data were collected. T tests have been conducted to compare the contributing factors between two periods. The injury severities are significantly different among all five levels between those during normal period and the Pandemic period. A crash predictive model has been developed to determine the facts to injury severity levels for motorcycle crashes. A total of eight variables are found to significantly increase the injury severity levels for motorcycle crashes during the Pandemic period.

关键词： Motorcycle Crash Pandemic Injury Severity Contributing factors

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

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Optimization of Diesel and Crude Oil Degradation in a Ghanaian Soil Using Organic Wastes as Amendment

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Journal of Agricultural Chemistry and Environment 2024年第1期13卷 1-12页

作者： Adama Sawadogo Innocent Yao Dotse lawson Hama Cissé Cheikna Zongo Aly Savadogo Laboratory of Applied Biochemistry and Immunology Research and Training Unit Life and Earth Sciences Joseph Ki-Zerbo University Ouagadougou Burkina Faso Soil Science Department School of Agriculture University of Ghana Accra Ghana

Soil contamination by hydrocarbons poses numerous environmental, health and agricultural problems. The degradation of these pollutants can occur naturally but very slowly. It is therefore generally necessary to stimulate this degradation by different means. Thus, this study aimed to improve the bio-degradation of diesel and crude oil in a Ghanaian soil by biostimulation. for this, the sampled soil was characterized by standard methods and contaminated with diesel and crude oil at a proportion of 1% (w/w). Then, contaminated soil samples were supplemented with biochar-compost, poultry manure or cow dung at the proportion of 10% (w/w). Periodically, fractions of these samples were taken to evaluate the density of hydrocarbon utilizing bacteria (HUB) and the residual quantities of diesel or crude oil. The characteristics of the soil used show the need for supplementation for better degradation of hydrocarbons. The results of the study show that supplementing the soil with organic substrates increases HUB loads in soils contaminated by diesel and crude oil. They also show that the residual quantities of diesel and crude oil are generally significantly lower in supplemented soils (p = 0.048 and p f the study.

关键词： Biodegradation Biostimulation Soil Diesel Crude Oil Organic Amendment Ghana

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

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