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Non-monotonic temperature evolution of nonlocal structure–dynamics correlation in Cuzr glass-forming liquids

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Chinese Physics B 2021年第7期30卷 370-375页

作者： W J Jiang m z Li Department of Physics and Beijing Key Laboratory of Opto-electronic Functional materials&micro-nano Devices Renmin University of ChinaBeijing 100872China

The structure–dynamics correlations in a nonlocal manner were investigated in Cuzr metallic glass-forming liquids via classical molecular dynamics simulations.A spatial coarse-graining approach was employed to incorporate the nonlocal structural information of given structural order parameters in the structure–dynamics *** is found that the correlation between structure order parameters and dynamics increases with increasing coarse-graining length and has a characteristic length ***,the characteristic correlation length exhibits a non-monotonic temperature evolution as temperature approaches glass transition temperature,which is not sensitive to the considered structure order *** results unveil a striking change in the structure–dynamics correlation,which involves no fitting theoretical *** findings provide new insight into the structure–dynamics correlation in glass transition.

关键词： metallic glass-forming liquid structure–dynamics correlation molecular dynamics simulation

Solidification, microstructure, and mechanical properties of the as-cast zRE1 magnesium alloy with different praseodymium contents

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International Journal of minerals,metallurgy and materials 2017年第11期24卷 1306-1320页

作者： z.m.Sheggaf R.Ahmad m.B.A.Asmael A.m.m.Elaswad Department of manufacturing and Industrial Engineering Faculty of Mechanical and Manufacturing Engineering Universiti Tun Hussein Onn Malaysia Parit Raja86400 BatuPahat Johor Malaysia Department of mechanical Engineering Eastern Mediterranean University North Cyprus Gazimagsa TRNC Mersin 10 Turkey

The influence of praseodymium(Pr) content on the solidification characteristics, microstructure, and mechanical properties of zRE1 magnesium(mg) cast alloy was investigated. The obtained solidification parameters showed that Pr strongly affected the solidification time, leading to refinement of the microstructure of the alloys. When the freezing time was reduced to approximately 52 s, the grain size decreased by 12%. mg_(12)zn(Ce,Pr) was formed as a new phase upon the addition of Pr and was detected via X-ray diffraction analysis. The addition of Pr led to a substantial improvement in mechanical properties, which was attributed to the formation of intermetallic compounds; the ultimate tensile strength and yield strength increased by approximately 10% and 13%, respectively. Pr addition also refined the microstructure, and the hardness was recovered. The results herein demonstrate that the mechanical properties of mg alloys are strongly influenced by their microstructure characteristics, including the grain size, volume fraction, and distribution of intermetallic phases.

关键词： metal solidification microstructure mechanical properties magnesium alloys intermetallics

Effect of Water Concentration on the Characterization of Sprayed Cd_(0.5)zn_(0.5)S Films

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Chinese Physics Letters 2011年第6期28卷 237-240页

作者： Sur S Öztürk z Öztaş.m Bedir m Özdemir Y Department of Engineering Physics University of GaziantepGaziantepTurkey Chemical and Process Engineering Department Yalova UniversityYalovaTurkey

Cd_(0.5)zn_(0.5)S film samples are prepared by a spray pyrolysis technique using aqueous solutions of CdC_(l2),znC_(l2),SC(NH2)2 and deionized water,which are atomized using compressed air as the carrier gas onto glass substrates with different water(H2O)concentrations.H2O is used as the *** prepared films are characterized by means of XRD and UV−VIS *** results reveal that the structures and properties of the films are greatly affected by the H2O *** in a certain range of concentrations promotes the formation of the Cd_(0.5)zn_(0.5)S films and improves the properties of the films.

关键词： spectroscopy pyrolysis

Fire resistance evaluation through synthetic fire tests and generative adversarial networks

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Frontiers of Structural and Civil Engineering 2024年第4期18卷 587-614页

作者： Aybike Özyüksel Çiftçioğlu m.z.Naser Department of Civil Engineering Manisa Celal Bayar University45140Türkiye School of Civil&Environmental Engineering and Earth Sciences(SCEEES) Clemson UniversityClemsonSC 29631USA Artificial Intelligence Research Institute for Science and Engineering(AIRISE) Clemson UniversityClemsonSC 29631USA

This paper introduces a machine learning approach to address the challenge of limited data resulting from costly and time-consuming fire experiments by enlarging small fire test data sets and predicting the fire resistance of reinforced concrete *** approach begins by creating deep learning models,namely generative adversarial networks and variational autoencoders,to learn the spatial distribution of real fire *** then use these models to generate synthetic tabular samples that closely resemble realistic fire resistance values for reinforced concrete *** generated data are employed to train state-of-the-art machine learning techniques,including Extreme Gradient Boost,Light Gradient Boosting machine,Categorical Boosting Algorithm,Support Vector Regression,Random Forest,Decision Tree,multiple Linear Regression,Polynomial Regression,Support Vector machine,Kernel Support Vector machine,Naive Bayes,and K-Nearest Neighbors,which can predict the fire resistance of the columns through regression and *** learning analyses achieved highly accurate predictions of fire resistance values,outperforming traditional models that relied solely on limited experimental *** study highlights the potential for using machine learning and deep learning analyses to revolutionize the field of structural engineering by improving the accuracy and efficiency of fire resistance evaluations while reducing the reliance on costly and time-consuming experiments.

关键词： deep learning fire resistance generative adversarial networks machine learning

RECENT DEVELOPmENTS IN mODELING THE DAmPING BEHAVIOR OF mmCs

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Acta metallurgica Sinica(English Letters) 2000年第2期13卷 715-721页

作者： J.C. Wang, z.m. zhang and G.C. Yang State Key Labortory of Solidification Processing, Northwestern Polytecnical University, Xi’an 710072, China

Taking three kinds of metal-matrix composites (mmCS) (laminated composites, fibers reinforced mmCs, and particle-reinforced mmCs)as examples, the recent develop ments in modeling the damping behaviors of mmCs are extensively reviewed. The damping mechanisms of different kinds of composites are quite different, and therefore, the analytical of numerical methods for different kinds of mmCs are also quite different. This will he shown in this extensive review. Furthermore, the directions of future developments in modeling the damping behavior of mmCs are also presented.

关键词： modeling mmCs damping behavior

Synthesis of self-assembled nanorod vanadium oxide bundles by sonochemical treatment

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Journal of Natural Gas Chemistry 2009年第3期18卷 312-318页

作者： Y.H.Taufiq-Yap Y.C.Wong z.zainal m.z.Hussein Centre of Excellence for Catalysis Science and Technology Faculty of ScienceUniversiti Putra Malaysia Department of Chemistry Faculty of ScienceUniversiti Putra Malaysia

Self-assembled nanorod of vanadium oxide bundles were synthesized by treating bulk V2O5 with high intensity sonochemical technique. The synthesized materials were characterized by X-ray diffraction （XRD）, scanning electron microscope （SEm）, transmission electron microscope （TEm） and temperature-programmed reduction （TPR） in H2. Catalytic behaviour of the materials over anaerobic n-butane oxidation was studied through temperature-programmed reaction （TPRn）. Catalytic evaluation of the sonochemical treated V2O5 products was also studied on microreactor. XRD patterns of all the vanadium samples were perfectly indexed to V2O5. The morphologies of the nanorod vanadium oxides as shown in SEm and TEm depended on the duration of the ultrasound irradiation. Prolonging the ultrasound irradiation duration resulted in materials with uniform, well defined shapes and surface structures and smaller size of nanorod vanadium oxide bundles. H2-TPR profiles showed that larger amount of oxygen species were removed from the nanorod V2O5 compared to the bulk. Furthermore, the nanorod vanadium oxide bundles, which were produced after 90, 120 and 180 min of sonochemical treatment, showed an additional reduction peak at lower temperature （-850 K）, suggesting the presence of some highly active oxygen species. TPRn in n-butane/He over these materials showed that the nanorod V2O5 with highly active oxygen species showed markedly higher activity than the bulk material, which was further proven by catalytic oxidation of n-butane.

关键词： nanorod vanadium oxide sonochemical treatment butane oxidation

ON THE TRANSIENT DEPARTURE PROCESS OF m^x/G/1 QUEUEING SYSTEm WITH SINGLE SERVER VACATION

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Journal of Systems Science & Complexity 2007年第4期20卷 562-571页

作者： Yinghui tang School of mathematics & software Science Sichuan Normal University Chengdu 610066 China

This paper studies the transient departure process of m^x/G/1 queueing system with single server vacation. We present a simple probability decomposition method to derive the expected number of departures occurring in finite time interval from any initial state and the asymptotic expansion of the expected number. Especially, we derive some more practical results for some special cases.

关键词： Asymptotic expansion expected number group arrival server vacation.

Transparent neural interfaces:challenges and solutions of microengineered multimodal implants designed to measure intact neuronal populations using high-resolution electrophysiology and microscopy simultaneously

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microsystems & Nanoengineering 2023年第3期9卷 1-30页

作者： z.Fekete A.zátonyi A.Kaszás m.madarász A.Slézia Research Group for Implantable microsystems Faculty of Information Technology&BionicsPázmány Péter Catholic UniversityBudapestHungary Institute of Cognitive Neuroscience&Psychology Eotvos Lorand Research NetworkBudapestHungary mines Saint-Etienne Centre CMPDépartement BELF-13541 GardanneFrance Institut de Neurosciences de la Timone CNRS UMR 7289&Aix-Marseille Université13005 MarseilleFrance János Szentágothai PhD Program of Semmelweis University BudapestHungary BrainVision Center BudapestHungary

The aim of this review is to present a comprehensive overview of the feasibility of using transparent neural interfaces in multimodal in vivo experiments on the central nervous *** electrophysiological and neuroimaging approaches hold great potential for revealing the anatomical and functional connectivity of neuronal ensembles in the intact *** approaches are less time-consuming and require fewer experimental animals as researchers obtain denser,complex data during the combined *** devices that provide high-resolution,artifactfree neural recordings while facilitating the interrogation or stimulation of underlying anatomical features is currently one of the greatest challenges in the field of *** are numerous articles highlighting the trade-offs between the design and development of transparent neural interfaces;however,a comprehensive overview of the efforts in material science and technology has not been *** present work fills this gap in knowledge by introducing the latest micro-and nanoengineered solutions for fabricating substrate and conductive ***,the limitations and improvements in electrical,optical,and mechanical properties,the stability and longevity of the integrated features,and biocompatibility during in vivo use are discussed.

关键词： modal resolution transparent

Spline Fictitious Boundary Element Alternating method for Edge Crack Problems with mixed Boundary Conditions

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Computer modeling in Engineering & Sciences 2018年第9期116卷 407-431页

作者： z.Xu m.Chen X.m.Fan School of Civil Engineering and Transportation South China University of TechnologyGuangzhouChina State Key Laboratory of Subtropical Building Science South China University of TechnologyGuangzhouChina

The alternating method based on the fundamental solutions of the infinite domain containing a crack,namely muskhelishvili’s solutions,divides the complex structure with a crack into a simple model without crack which can be solved by traditional numerical methods and an infinite domain with a crack which can be solved by muskhelishvili’s ***,this alternating method cannot be directly applied to the edge crack problems since partial crack surface of muskhelishvili’s solutions is located outside the computational *** this paper,an improved alternating method,the spline fictitious boundary element alternating method(SFBEAm),based on infinite domain with the combination of spline fictitious boundary element method(SFBEm)and muskhelishvili’s solutions is proposed to solve the edge crack *** the SFBEm and muskhelishvili’s solutions are obtained in the framework of infinite domain,no special treatment is needed for solving the problem of edge *** mixed boundary conditions edge crack problems with varies of computational parameters are given to certify the high precision,efficiency and applicability of the proposed method compared with other alternating methods and extend finite element method.

关键词： Spline fictitious boundary element alternating method mixed boundary conditions edge crack problem muskhelishvili’s solutions stress intensity factor