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Exploring the mechanical behavior and microstructure of compacted loess subjected to dry-wet cycles and chemical contamination

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Journal of Rock.Mechanics and Geotechnical Engineering 2024年第9期16卷 3673-3695页

作者： Yongpeng Nie Wank.i Ni Xiangfei lü Wenxin Tuo College of Geological Engineering and Geomatics Chang'an UniversityXi'an710054China Department of Civil Engineering Nagoya Institute of TechnologyNagoya466-8555Japan School of Water and Environment Chang'an UniversityXi'an710054China

Due to climatic factors and rapid urbanization,the soil in the loess Plateau,China,experiences the coupled effects of dry-wet cycles and chemical *** the mechanical behavior and corresponding microstructural evolution of contaminated loess subjected to dry-wet cycles is essential to elucidate the soil degradation ***,direct shear and consolidation tests were performed to investigate the variations in mechanical properties of compacted loess contaminated with acetic acid,sodium hydroxide,and sodium sulfate during dry-wet *** mechanical response mechanisms were investigated using zeta potential,mineral chemical composition,and scanning electron microscopy(SEM)*** results indicate that the mechanical deterioration of sodium hydroxidecontaminated loess during dry-wet cycles decreases with increasing contaminant concentration,which is mainly attributed to the thick.ning of the electrical double layer(EDl)by Nat and the precipitation of calcite,as well as the formation of colloidal flocs induced by OH,thus inhibiting the development of large pores during the dry-wet *** contrast,the attenuation of mechanical properties of both acetic acid-and sodium sulfate-contaminated loess becomes more severe with increasing contaminant concentration,with the latter being more particularly *** is primarily due to the reduction of the EDl thick.ess and the erosion of cement in the acidic environment,which facilitates the connectivity of pores during dry-wet ***,the salt expansion generated by the drying process of saline loess further intensifies the structural ***,the mechanical performance of compacted loess is sensitive to both pollutant type and concentration,exhibiting different response patterns in the dry-wet cycling condition.

关键词： Contaminated loess Dry-wet cycles Compressibility Shear strength Microstructural evolution

A comprehensive review on the processing-property relationships of laser strengthened magnesium

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Journal of Magnesium and Alloys 2024年第1期12卷 1-34页

作者： Alessandro M.Ralls Aak.heta Agnel Pradeep l.Menezes Department of Mechanical Engineering University of Nevada RenoRenoNV 89557United States

Among the existing series of softer metals,magnesium(Mg)has attracted much attention due to its impressive strength-to-weight ***,due to its ease of deformability,Mg tends to suffer from rapid degradation in a wide variety of abrasive and electrochemical *** method of improving its surface properties is through surface modification *** the existing techniques,laser shock.peening(lSP)has been one of the most widely utilized processes due to its surface-hardening-lik. *** this understanding,a comprehensive review has yet to exist that encapsulates the strengthening mechanism of lSP for Mg and its influence in degradation *** review aims to encapsulate the existing research around the lSP field for ***,an understanding of the surface-strengthening effects in relation to its mechanical,tribological,corrosion,and tribo-corrosion characteristics is ***,the feasibility of lSP for Mg materials in critical industries is also *** this work.a novel understanding of lSP for Mg can be understood,which can provide a future direction for research in this field.

关键词： laser shock.peening Magnesium Surface deformation Tribology Microstructure

Novel medium entropy perovsk.te oxide Sr(FeCoNiMo)_(1/4)O_(3−δ)for zinc-air battery cathode

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Journal of Energy Chemistry 2024年第9期96卷 669-678页

作者： k.ixin li Juntao Gao Xu Han Qi Shao Zhe lü School of Physics Harbin Institute of TechnologyHarbin 150001HeilongjiangChina Heilongjiang Provincial k.y laboratory of Advanced Quantum Functional Materials and Sensor Components Harbin 150001HeilongjiangChina

It is widely recognized that the development of ZABs is impeded by the k.netic bottleneck.of oxygen evolution reaction(OER)and oxygen reduction reaction(ORR).The application of conformational entropy strategy to oxides often involves introducing multiple elements with different properties,thereby providing outstanding bifunctional catalytic activity for OER/***,the possible underlying catalytic pathways and potential interactions between various components are still poorly *** paper presents an excellent medium-entropy perovsk.te oxide,Sr(FeCoNiMo)_(1/4)O_(3−δ)(lower overpotential of 301 mV at 10 mA cm^(−2)).Zinc-air batteries employing it as a cathode catalyst demonstrate excellent round-trip efficiency(62%).By combining theoretical calculation with experiments,we aim to establish the link.between the electronic structure of perovsk.te oxides with different elemental compositions and their OER *** reveals that the conformational entropy strategy can simultaneously shift the O 2p-band center and metal d-band center of perovsk.te oxide towards the vicinity of the Fermi energy level,thereby triggering a more favorable lattice oxygen-participated mechanism(lOM)during the OER *** outcomes of this work.provide crucial insights into the role of conformational entropy strategies in oxygen catalysis and offer potential avenues for constructing efficient and stable electrocatalysts.

关键词： Sr(FeCoNiMo)_(1/4)O_(3−δ) Bifunctional catalyst Medium entropy lOM Rechargeable zinc-air batteries

Biomaterials and emerging technologies for tissue engineering and in vitro models

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Bio-Design and Manufacturing 2024年第3期7卷 237-239页

作者： J.Miguel Oliveira Rui l.Reis 3B’s Research Group I3Bs-Research Institute on BiomaterialsBiodegradables and BiomimeticsHeadquarters of the European Institute of Excellence on Tissue Engineering and Regenerative MedicineUniversity of MinhoAveParkZona Industrial da Gandra4805-017 BarcoGuimarãesPortugal ICVS/3B’s-PT Government Associate laboratory 4806-909 Braga/GuimarãesPortugal

The latest advances in the field of biomaterials have opened new avenues for scientific break.hroughs in tissue engineer-ing which greatly contributed for the successful translation of tissue engineering products into the mark.t/***-materials are easily processed to become similar to natural extracellular matrix,mak.ng them ideal temporary supports for mimick.ng the three-dimensional(3D)microenvironment required for maintaining the adequate cell/tissue functions both in vitro and in vivo^([1]).

关键词： break.hrough biomaterials engineer

Spark.Plasma Sintering of Mg-based Alloys:Microstructure,Mechanical Properties,Corrosion Behavior,and Tribological Performance

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Journal of Magnesium and Alloys 2024年第2期12卷 405-442页

作者： Alessandro M.Ralls Mohammadreza Daroonparvar Pradeep l.Menezes Department of Mechanical Engineering University of Nevada RenoRenoNV89557United States

Within the past ten years,spark.plasma sintering(SPS)has become an increasingly popular process for Mg *** the SPS process,interparticle diffusion of compressed particles is rapidly achieved due to the concept of Joule *** to traditional and additive manufacturing(AM)techniques,SPS gives unique control of the structural and microstructural features of Mg *** doing so,their mechanical,tribological,and corrosion properties can be *** great advancements in this field have been made,these pieces of k.owledge are scattered and have not been contextualized into a single *** motivation of this work.is to address this scientific gap and to provide a groundwork.for understanding the basics of SPS manufacturing for *** do so,the existing body of SPS Mg literature was first surveyed,with a focus on their structural formation and degradation *** was found that successful Mg SPS fabrication highly depended on the processing temperature,particle size,and particle *** addition of metal and ceramic composites also affected their microstructural features due to the Zener pinning *** degradative environments,their performance depends on their structural features and whether they have secondary phased *** industrial applications,SPS'd Mg was found to have great potential in biomedical,hydrogen storage,battery,automotive,and recycling *** prospects to advance the field include using Mg as a doping agent for crystallite size refinement and using bulk.metallic Mg-based glass powders for amorphous SPS *** these findings,the interactions of multi-composites on the processing-structure-property relationships of SPS Mg is not well *** total,this work.will provide a useful direction in the SPS field and serve as a milestone for future Mg-based SPS manufacturing.

关键词： Spark.plasma sintering Magnesium alloys Nanocrystalline Tribology Mechanical properties Corrosion

A seed and soil model of loneliness in Alzheimer's disease

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Neural Regeneration Research 2024年第12期19卷 2575-2576页

作者： Hannah l.Apostolou Ian M.McDonough Department of Psychology The University of AlabamaTuscaloosaALUSA Department of Psychology Binghamton UniversityBinghamtonNYUSA

loneliness is classically defined as a result of perceiving a discrepancy between the desired quantity and quality of one's social life and actual social relationships(Perlman and Peplau,1984).lifespan research has indicated older adults are among the highest risk.for experiencing loneliness because their social network.size decreases more frequently than that of younger adults.

关键词： Alzheimer younger soil

Error-based adaptive optimal track.ng control of nonlinear discrete-time systems

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Science China(Information Sciences) 2024年第1期67卷 154-167页

作者： Chun lI Jinliang DING Frank.l.lEWIS Tianyou CHAI State k.y laboratory of Synthetical Automation for Process Industries Northeastern University UTA Research Institute The University of Texas at Arlington

In this paper,for the output track.ng problem of nonlinear discrete-time systems,a performance index is newly defined using the adaptive dynamic programming(ADP) technique to completely eliminate track.ng errors in *** contrast to traditional definitions of performance indices in other ADP-based methods,the proposed performance index is not only designed from the perspective of output track.ng errors but also introduced errors of system states and control inputs at adjacent stages,which is suitable for practical situations in many industrial applications,such as the alumina production,the flotation process,and the mineral grinding *** proved that the obtained controller can mak. the system output fully track.the given reference trajectory by applying the iterative criteria of the ADP *** addition,the proposed algorithm was implemented using a data-driven technique and neural network. to avoid analyzing and deducing the complicated dynamics of actual industrial ***,using historical data for a forced-circulation evaporation system in the alumina production process,the effect of the proposed approach was verified through a numerical simulation and compared with that of the proportional-integral controller.

关键词： adaptive dynamic programming iterative criteria performance index track.ng errors track.ng problem

Direct joining of oxygen-free copper and carbon-fiber-reinforced plastic by friction lap joining

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Journal of Materials Science & Technology 2018年第1期34卷 192-197页

作者： l.H. Wu k. Nagatsuk. k. Nak.ta Joining and Welding Research Institute Osaka University 11-1 Mihogaoka Ibaraki Osaka 567-0047 Japan

Oxygen-flee copper （Cu） was successfully joined to carbon-fiber-reinforced thermoplastic （CFRTP, polyamide 6 with 20wt% carbon fiber addition） by friction lap joining （FlJ） at joining speeds of 200-1600 mm/min with a constant rotation rate of 1500 rpm and a nominal plunge depth of 0.9 ram. It is the first time to report the joining of CFRTP to Cu by FlJ. As the joining speed increased, the tensile shear force （TSF） of joints increased first, and decreased thereafter. The maximum TSF could reach 2.3 k. （ 15 mm in width）. Hydrogen bonding formed between the amide group of CFRTP and the thin Cu20 layer on the Cu surface, which mainly contributed to the joint bonding. The influence factors of the TSF of the joints at different joining speeds were discussed. The TSF was mainly affected by the joining area, the degradation of the plastic matrix and the number and the size of bubbles. As the joining speed increased, the influence factors varied as follows： the joining area increased first and then decreased; the degra- dation of the plastic matrix and the number and the size of bubbles decreased. The maximum TSF was the comprehensive result of the relatively large joining area, small degradation of the plastic matrix and small number and sizes of bubbles.

关键词： Friction lap joining Metal Plastic Carbon-fiber reinforced thermoplastic Dissimilar materials joining

Enhancing force sensing in a squeezed optomechanical system with quantum nondemolition measurement

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Communications in Theoretical Physics 2024年第1期76卷 49-60页

作者： Shi-lei Chao Zi-Hao li Xin-You lü School of Physics Huazhong University of Science and Technology430074 WuhanChina

A theoretical scheme is proposed to enhance the sensitivity of force sensors with quantum nondemolition measurement(QND)in an optomechanical setup assisted by four-tone optical driving and an optical parametric amplifier(OPA).With the help of special drive,the system can be simplified as the typical type of QND for force sensing,so that the back.ction noise can be evaded to surpass the standard quantum ***,the added noise can be suppressed owing to the modified optical susceptibility resulting from the *** introducing two oscillators coupling with two charged bodies respectively,the signal can be enhanced with the nonlinearity caused by Coulomb interaction,while the noise presents an exponential ***,considering the homodyne detection effect,the range of system parameters and frequency bands will be *** present investigation may provide a route toward simultaneously evading back.ction noise,reducing the mechanical thermal noise,and enhancing the external signal,which can be an alternative design for sensitive devices.

关键词： force sensing optical parametric amplifier quantum non-demolition measurement optomechanical system