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Near resonance vibration isolation on a levered-dual response(LEDAR)coulomb-damped system by differential preloads/offsets in linear springs

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Applied Mathematics and Mechanics(English Edition) 2024年第6期45卷 1033-1050页

作者： T.i.TOLUWALOJU c.K.THEiN D.HALiM Department of Mechanical Materials and Manufacturing EngineeringUniversity of Nottingham Ningbo ChinaNingbo 315100Zhejiang ProvinceChina Nottingham Ningbo c.ina Beacons of Excellence Research and innovation institute University of Nottingham Ningbo ChinaNingbo 315048Zhejiang ProvinceChina

The levered-dual response(LEDAR)coulomb-damped system attains near resonant vibration isolation by differential preloads/offsets in linear *** takes the advantages of both the preloads/offsets in linear springs and the guiderail fric.ion for realizing different levels of vibration *** isolation capacities are investigated on the strategies with both the horizontal and vertical guiderails,with the horizontal rail only,and without *** compressive preloads generally result in the consumption of most of the initial excitation energy so as to overcome the potential *** isolation onsets at the frequency ratio of 1∓0.095 on the left-hand side(LHS)and the right-hand side(RHS)of the lever are relative to the load plate *** observed near resonant isolation thus makes the LEDAR system a candidate for the isolation of the mechanical systems about resonance while opening a path for simultaneous harvesterisolation func.ions and passive func.ions at extreme frequencies.

关键词： lever ratio coulomb damping preload tension/compression isolation band/depth offset potential

Pathogenic and therapeutic role of exosomes in neurodegenerative disorders

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Neural Regeneration Research 2024年第1期19卷 75-79页

作者： christa c.Huber Hongmin wang Division of Basic Biomedical Sciences Sanford School of MedicineUniversity of South DakotaVermillionSDUSA

Neurodegenerative disorders affect millions of people worldwide,and the prevalence of these disorders is only projected to rise as the number of people over 65 will drastically increase in the coming *** therapies exist to aid in symptomatic relief,effec.ive treatments that can stop or reve rse the progress of each neurodegenerative disease are ***,research on the role of extracellular vesicles as disease markers and therapeutics has been intensively ***,30-150 nm in diameter,are one type of extracellular vesicles facilitating cell-to-cell *** are thought to play a role in disease propagation in a variety of neurodegenerative diseases,such as Alzheimer's disease,Parkinson s disease,and amyotrophic lateral ***,the exosomes derived from the patients are an invaluable source of disease *** the other hand,exosomes,especially those derived from stem cells,could serve as a therapeutic for these disorders,as seen by a rapid increase in c.inical trials investigating the therapeutic efficacy of exosomes in different neurological *** review summarizes the pathological burden and therapeutic approach of exosomes in neurodegenerative *** also highlight how heat shock increases the yield of exosomes while still maintaining their therapeutic ***,this review concludes with outstanding questions that remain to be addressed in exosomal research.

关键词： aging Alzheimer's disease biomarker drug exosome extracellular vesicle neurodegenerative disease Parkinson's disease therapy

Automated Mac.ine Learning Algorithm Using Recurrent Neural Network to Perform Long-Term Time Series Forecasting

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computers, Materials & continua 2024年第3期78卷 3529-3549页

作者： Ying Su Morgan c.wang Shuai Liu Department of Statistics and Data Science University of Central FloridaOrlandoFL32816-2370USA School of Mathematics and Statistics Beijing Technology and Business UniversityBeijing100048China

Long-term time series forecasting stands as a crucial research domain within the realm of automated mac.ine learning(AutoML).At present,forecasting,whether rooted in mac.ine learning or statistical learning,typically relies on expert input and necessitates substantial manual *** manual effort spans model development,feature engineering,hyper-parameter tuning,and the intricate construc.ion of time series *** complexity of these tasks renders complete automation unfeasible,as they inherently demand human intervention at multiple *** surmount these challenges,this article proposes leveraging Long Short-Term Memory,which is the variant of Recurrent Neural Networks,harnessing memory cells and gating mechanisms to facilitate long-term time series ***,forecasting accuracy by particular neural network and traditional models can degrade significantly,when addressing long-term time-series ***,our research demonstrates that this innovative approach outperforms the traditional Autoregressive integrated Moving Average(ARiMA)method in forecasting long-term univariate time *** is a high-quality and competitive model in time series predic.ion,and yet it requires significant preprocessing *** multiple accuracy metrics,we have evaluated both ARiMA and proposed method on the simulated time-series data and real data in both short and long ***,our findings indicate its superiority over alternative network arc.itectures,including Fully connected Neural Networks,convolutional Neural Networks,and Nonpooling convolutional Neural *** AutoML approach enables non-professional to attain highly accurate and effec.ive time series forecasting,and can be widely applied to various domains,particularly in business and finance.

关键词： Automated mac.ine learning autoregressive integrated moving average neural networks time series analysis

A Sharding Scheme Based on Graph Partitioning Algorithm for Public Blockchain

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computer Modeling in Engineering & Sciences 2024年第6期139卷 3311-3327页

作者： Shujiang Xu Ziye wang Lianhai wang Miodrag J.Mihaljevi′c Shuhui Zhang Wei Shao Qizheng wang Key Laboratory of computing Power Network and information Security Ministry of EducationShandong Computer Science CenterQilu University of Technology(Shandong Academy of Sciences)Jinan250014China Shandong Provincial Key Laboratory of computer Networks Shandong Fundamental Research Center for Computer ScienceJinan250014China Mathematical institute The Serbian Academy of Sciences and ArtsBelgrade11000Serbia

Blockchain technology,with its attributes of decentralization,immutability,and traceability,has emerged as a powerful catalyst for enhancing traditional industries in terms of optimizing business ***,transac.ion performance and scalability has become the main challenges hindering the widespread adoption of *** to its inability to meet the demands of high-frequency trading,blockchain cannot be adopted in many *** improve the transac.ion capacity,researchers have proposed some on-chain scaling technologies,including lightning networks,directed acyc.ic graph technology,state channels,and shardingmechanisms,inwhich sharding emerges as a potential scaling ***,excessive cross-shard transac.ions and uneven shard workloads prevent the sharding mechanism from ac.ieving the expected *** paper proposes a graphbased sharding scheme for public blockchain to efficiently balance the transac.ion *** crossshard transac.ions and evening-out workloads among shards,the scheme reduces transac.ion confirmation latency and enhances the transac.ion capacity of the ***,the scheme can ac.ieve a high-frequency transac.ion as well as a better blockchain *** results show that the scheme effec.ively reduces the cross-shard transac.ion ratio to a range of 35%-56%and significantly decreases the transac.ion confirmation latency to 6 s in a blockchain with no more than 25 shards.

关键词： Blockchain sharding graph partitioning algorithm

Mechanistic.insight into cr(Ⅵ)retention by Si-containing ferrihydrite

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Journal of Environmental Sciences 2024年第5期139卷 217-225页

作者： Ying Hu Qiang Xue Honghan chen Huaming Guo Kenneth c.carroll Song wang MOE Key Laboratory of Groundwater circulation and Environmental Evolution School of Water Resources and EnvironmentChina University of Geosciences(Beijing)Beijing 100083China Beijing Key Laboratory of Water Resources and Environmental Engineering School of Water Resources and EnvironmentChina University of GeosciencesBeijing 100083China State Key Laboratory of Biogeology and Environmental Geology China University of GeosciencesBeijing 100083China Plant&Environmental Science New Mexico State UniversityNM 88003USA institute of Theoretical chemistry College of ChemistryJilin UniversityChangchun 130023China

Hexavalent chromium[cr(Ⅵ)]causes serious harm to the environment due to its high toxicity,solubility,and ***(Fh)are the main adsorbent and trapping agent of cr(Ⅵ)in soils and aquifers,and they usually coexist with silicate(Si),forming Si-containing ferrihydrite(Si-Fh)***,the mechanism of cr(Ⅵ)retention by Si-Fh mixtures is poorly *** this study,the behaviors and mechanisms of cr(Ⅵ)adsorption onto Si-Fh with different Si/Fe molar ratios was *** electron microscope,Fourier transform infrared spectroscopy,X-ray diffrac.ion,X-ray photoelectron spectroscopy,and other techniques were used to characterize Si-Fh and cr(Ⅵ)-loading of *** results show that specific surface area of Si-Fh increases gradually with increasing Si/Fe ratios,but cr(Ⅵ)adsorption on Si-Fh decreases with increasing Si/Fe *** is because with an increase in Si/Fe molar ratio,the point of zero charge of Si-Fh gradually decreases and electrostatic repulsion between Si-Fh and cr(Ⅵ)***,the complexation of cr(Ⅵ)is enhanced due to the increase in adsorbed hydroxyl(A-OH-)on Si-Fh with increasing Si/Fe molar ratio,which partly counteracts the effect of the electrostatic ***,the increase in the electrostatic repulsion has a greater impact on adsorption than the additional complexation with *** func.ional theory calculation further supports this observation,showing the increases in electron variation of bonding atoms and reac.ion energies of inner spherical complexes with the increase in Si/Fe ratio.

关键词： Hexavalent chromium Ferrihydrite Si/Fe ratio cr(Ⅵ)Adsorption

Progress on the antiferromagnetic topological insulator MnBi2Te4

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National Science Review 2024年第2期11卷 33-49页

作者： Shuai Li Tianyu Liu chang Liu Yayu wang Hai-Zhou Lu X.c.Xie Department of Physics Harbin Institute of Technology Shenzhen institute for Quantum Science and Engineering and Department of Physics Southern University of Science and Technology(SUSTech) Quantum Science center of Guangdong-Hong Kong-Macao Greater Bay Area(Guangdong) Shenzhen Key Laboratory of Quantum Science and Engineering international Quantum Academy Beijing Academy of Quantum information Sciences Beijing Key Laboratory of Optoelectronic Func.ional Materials&Micro-Nano Devices Department of Physics Renmin University of China State Key Laboratory of Low Dimensional Quantum Physics Department of PhysicsTsinghua University Frontier Science center for Quantum information Hefei National Laboratory international center for Quantum Materials School of Physics Peking University institute for Nanoelectronic Devices and Quantum computing Fudan University

Topological materials, which feature robust surface and/or edge states, have now been a research focus in condensed maTher physics. They represent a new class of materials exhibiting nontrivial topological phases,and provide a platform for exploring exotic transport phenomena, such as the quantum anomalous Hall effect and the quantum spin Hall effect. Recently, magnetic topological materials have attracted considerable interests due to the possibility to study the interplay between topological and magnetic *** particular, the quantum anomalous Hall and axion insulator phases can be realized in topological insulators with magnetic order. MnBi2Te4, as the first intrinsic antiferromagnetic topological insulator discovered, allows the examination of existing theoretical predic.ions; it has been extensively studied, and many new discoveries have been made. Here we review the progress made on MnBi2Te4from both experimental and theoretical aspects. The bulk crystal and magnetic structures are surveyed first, followed by a review of theoretical calculations and experimental probes on the band structure and surface states, and a discussion of various exotic phases that can be realized in MnBi2Te4. The properties of MnBi2Te4thin films and the corresponding transport studies are then reviewed, with an emphasis on the edge state transport. Possible future research direc.ions in this field are also discussed.

关键词： MnBi2Te4 magnetic topological insulator antiferromagnetic quantum anomalous Hall effect axion insulator

investigations of nuclear c.irality at iThemba LABS

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Frontiers of physics 2024年第2期19卷 7-38页

作者： R.A.Bark E.A.Lawrie c.Liu S.Y.wang iThemba Laboratory for Accelerator Based Sciences National Research FoundationP.O.Box 722Somerset-West 7129South Africa Department of Physics University of the Western CapePrivate Bag X177535BellvilleSouth Africa Shandong Provincial Key Laboratory of Optical Astronomy and Solar-Terrestrial Environment Institute of Space SciencesShandong UniversityWeihai 264209China

Progress in the studies of c.irality in atomic nuclei at iThemba LABS is *** regions of c.irality,around mass 80 and 190 have been discovered using the AFRODiTE array,specifically in the nuclei^(74)As,^(78,80,82)Br,^(81)Kr,and^(193,194,198)*** phenomena have been observed,including multiple c.iral bands in the same nucleus,the coexistence of octupole correlations and nuclear c.irality,and the coexistence of pseudo spin and nuclear *** best example of c.iral degeneracy to date was found in ^(194)*** level scheme of ^(106)Ag has been revisited and interpreted in terms of two-and four-quasiparticle *** using the particle-rotor model have shown that the fingerprints of c.irality in the two-quasiparticle system only can occur in an idealised model *** systems with a higher number of quasiparticles,the calculations showed that nuclear c.irality can persist.

关键词： c.irality high-spin states particle-rotor model

Slope stability of reclaimed coal mines through a new water filling index

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第3期16卷 828-839页

作者： Antonios Mikroutsikos Alexandros i.Theocharis Nikolaos c.Koukouzas ioannis E.Zevgolis chemical Process&Energy Resources institute Centre for Research&Technology HellasAthensGreece School of Mining and Metallurgical Engineering National Technical University of AthensAthensGreece

A common reclamation prac.ice for closed coal surface mines is filling them with water to form pit *** creation and sustainability of these lakes are significantly affected by the stability of the corresponding *** present study provides a general framework for analyzing the water filling’s effect on slope stability based on a new water filling index,which can indirectly consider the factors affec.ing the process and efficiently quantify the filling speed’s *** assumptions of the proposed approach are thoroughly discussed,and the range of the water filling index is ***,the safety factor is calculated using the finite element method with the shear strength reduc.ion technique during the filling process for various conditions(soil properties,slope geometry,hydraulic conditions,and water filling speed).Results are presented as normalized stability charts for prac.ical *** the water filling,the stability gradually decreases until the reservoir reaches a c.itical level of 10%e40%of the total height;it then increases to even more stable conditions than the initial ***,the present analysis allows for the preliminary stability evaluation of a coal mine during the formation of a pit lake and the appropriate quantification of the water filling’s effect.

关键词： Post-coal era Open-pit flooding Stability charts c.itical level

carbon coated LaFe_(0.92)Pd_(0.08)O_(3) composites for catalytic transfer hydrogenation:Balance in the ability of substrates adsorption and conversion

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Nano Research 2024年第5期17卷 3724-3732页

作者： Bowen wang Nan Zhang Ping Xiao Jian Zhang Sónia A.c.carabineiro Junjiang Zhu Hubei Key Laboratory of Biomass Fibers and Eco-dyeing&Finishing College of Chemistry and Chemical EngineeringWuhan Textile UniversityWuhan 430200China college of chemistry and Materials Engineering Wenzhou UniversityWenzhou 325035China LAQV-REQUiMTE Department of ChemistryNOVA School of Science and TechnologyUniversidade NOVA de LisboaLargo da Torre2829-516 CaparicaPortugal

catalytic transfer hydrogenation(cTH)is a green and efficient pathway for selec.ive hydrogenation of unsaturated aldehydes and ***,managing the abilities of solid catalysts to adsorb substrates and to convert them into desired products is a challenging ***,we report the synthesis of carbon coated LaFe_(0.92)Pd_(0.08)O_(3) composites(LFPO-8@c)for cTH of benzaldehyde(BzH)into benzyl alcohol(BzOH),using isopropanol(iPA)as hydrogen *** coating with carbon improves the ability to adsorb/transfer reactants from solution to ac.ive sites,and the doping of Pd2+at Fe3+site strengthens the ability of LaFeO_(3) to convert BzH into BzOH.A balanced point between them(i.e.,abilities to adsorb BzH and to convert BzH into BzOH)is obtained at LFPO-8@c,which exhibits a BzOH formation rate of 3.88 mmol·gcat^(-1)·h^(-1) at 180℃ for 3 h,which is 1.50 and 2.72 times faster than those of LFPO-8 and LaFeO_(3)@c.A reac.ion mechanism is proposed,in which the acidic sites(e.g.,Fe^(4+),oxygen vacancy)are used for the ac.ivation of c=O bond of BzH and O-H bond of iPA,and the basic sites(e.g.,lattice oxygen)for the ac.ivation ofα-H(O-H)bond of iPA.

关键词： LaFe_(0.92)Pd_(0.08)O_(3) porous carbon catalytic transfer hydrogenation isopropanol reac.ion mechanism