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Journal of Materials Science & technology 1996年第2期12卷 135-142页

作者： Ren, XB Wang, Xt Shimizu, K tadaki, t XIAN JIAOtONG UNIV COLL MAT SCI & ENGNXIAN 710049PEOPLES R CHINA OSAKA UNIV INST SCI & IND RESIBARAKIOSAKA 567JAPAN

A theory recently developed by the present authors is applied to the study of the effect of elastic energy due to atomic size factor on the transformation behaviour of binary solid solutions. It is found that elastic interaction energy (EIE), which is a part of the total elastic energy, plays a key role in both ordering elastic interaction ordering (EIO) and spinodal decomposition. the present study gives a reasonable explanation to the historical dilemmas, ''elastic energy paradox'' and ''atomic size factor paradox''. By solving these confusing problems, the coexistence of ordering (EIO) and decomposition, which has been regarded as impossible by conventional theories, can be well understood. the mechanism is as follows: lowering of elastic energy demands EIO, and such an ordering provides a driving force for spinodal decomposition. therefore, in alloys with large atomic size factor, spinodal decomposition is preceded and induced by ordering. Ordering and spinodal decomposition are thus closely related processes to each other.

关键词： Solid solutions

Elastic Energy and Elastic Interaction Ordering of Binary Solid Solutions

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Journal of Materials Science & technology 1996年第1期12卷 57-68页

作者： Ren, XB Wang, Xt Shimizu, K tadaki, t XIAN JIAOtONG UNIV COLL MAT SCI & ENGN XIAN 710049 PEOPLES R CHINA OSAKA UNIV INST SCI & IND RES IBARAKI OSAKA 567 JAPAN

A theory in the framework of continuum elasticity has been developed to calculate the total contribution of ''atomic size effect'' or ''strain energy effect'' to free energy of binary solid solutions. It is found that elastic free energy consists of two parts: elastic self energy (ESE), and elastic interaction energy(EIE). the former is a function of composition alone, the latter is also a function of atomic configuration. Minimization of total elastic free energy with respect to atomic arrangement results in an ordered arrangement of atoms, which is called elastic interaction ordering (EIO), as it originates from elastic interaction among atoms. EIO is a kind of local ordering within a ''characteristic range'', and it is found to be important in determining the state of solid solutions and structures of superlattices. the present theory also gives good explanation to the coexistence of ordering and decomposition which can not be understood in conventional theories.

关键词： Solid solutions

Origin of Ordering Coupled tweed Microstructures in Alloys with Large Atomic Size Factors

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Journal of Materials Science & technology 1996年第3期12卷 166-174页

作者： Ren, XB Wang, Xt Shimizu, K tadaki, t XIAN JIAOtONG UNIV COLL MAT SCI & ENGNXIAN 710049PEOPLES R CHINA OSAKA UNIV INST SCI & IND RESIBARAKIOSAKA 567JAPAN

A theoretical study is developed on the evolution and mechanism of an ordering coupled phase separation, and on the origin of a resultant tweed microstructure. It is found that long-range elastic interaction among atoms with different atomic sizes plays a key role in the phase separation, and that the evolution of the phase separation is very similar to that of conventional spinodal decomposition except that the separation is dependent on an elastic interaction ordering (EIO). this ''EIO coupled spinodal decomposition'' is shown to exhibit a periodical or tweed microstructure being accompanied by an EIO. It is also found that a large atomic size factor yields a large positive contribution of EIO to spinodal decomposition. Generally, it is thermodynamically and kinetically favorable for the EIO to precede the onset of spinodal decomposition, though the former is not separable from the latter as a whole. We suggest that an initially disordered solid solution undergoes an EIO first, and then the partially ordered solid solution starts to decompose via a spinodal mechanism. Solute-enriched regions increase their degree of order along with an increase in solute content, and solute-depleted regions decrease their degree of order together with a decrease of solute content. the final microstructure is characterized by a periodical array of highly ordered solute-enriched regions and nearly disordered solute-depleted regions. the notion of EIO coupled spinodal decomposition is in general agreement with the transformation behaviour of a large number of alloy systems.

关键词： SPINODAL DECOMPOSItION tItANIUM ALLOYS tI ALLOYS tRANSFORMAtIONS NICKEL LI

theoretical study of coexistence of ordering and spinodal decomposition

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Science China(technological Sciences) 1996年第4期39卷 412-423页

作者：任晓兵王笑天 t.tadaki K.Shimizu National Laboratory of Solid State Microstructures Nanjing UniversityNanjing 210093China College of Materials Science and Engineering Xi'an Jiaotong UniversityXi'an 710049. China Institute for Scientific and Industrial Research Osaka UniversityOsaka 567Japan Department of Mechanical Engineering Kanazawa Institute of TechnologyIshikawa 921Japan

According to the conventional theory of solid solutions (the nearest neighbor atomic interaction model),ordering and spinodal decomposition/clustering are mutually exclusive ***,it has been found that the coexistence of ordering and spinodal decomposition (COSD) occurs in a large number of *** fact gave a strong challenge to the conventional theory.A statistical investigation revealed that the COSD was closely related to large atomic-siae *** was thus proposed that the COSD stemmed from the long-range elastic interactions due to atomic-si?E *** order to verify this idea,the formulism of concentration waves was applied to calculating the elastic *** results proved that long-range atomic elastic interactions promoted both ordering and spinodal decomposition.A possible application of the COSD reaction was proposed,*** this reaction to fabricate high-performance "natural nano-alloys".

关键词： ordering and spinodal decomposition elastic interactions atomic-size factor phase transformation nano-materials.

CRYStAL　StRUCtURE　OF　A　LONG－PERIOD　ORDERED　PHASE　IN　Fe－C　MARtENSItE　AND　COMPUtER　SIMULAtION　OF　ItS　ELECtRON　DIFFRACtION　PAttERNS

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Acta Metallurgica Sinica(English Letters) 1996年第1期9卷 23-26页

作者： REN Xiaobing WANG Xiaotian K.SHIMIZU t.tadaki(National Laboratory of Solid State Microstructures,Nanjing University Nanjing 210093,China)(School of Materials Science and Engineering,Xi’an Jiaotong University Xi’an 710049,China)(Kanazawa Institute of techn Nanjing Univ Nanjing China

Different structure models of a long-period ordered phase in Fe-C martenstie formed during aging have been checked by computer simulation of electron diffraction(ED) patterns based on these *** results showed that the simulated ED pattern of γ'-FexC(Ⅱ) model proposed by the present authors is in good agreement with experimentally observed ED *** was also confirmed that the incommensurate superperiod stems from the coexistence of several γ'-Fe_xC(H) phases with different *** Fe(144)C(24)(Fe6C) model proposed by Uwakweh et *** ED patterns remarkably different from the experimental ones.

关键词： Fe-C martensite long-period ordered phase crystal structure computer simulation electron diffraction pattern

Preparation of microparticles and nanoparticles using membrane-assisted dispersion,micromixing,and evaporation processes

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Particuology 2024年第1期84卷 30-44页

作者： Goran t.Vladisavljevic Chemical Engineering Department Loughborough UniversityLoughboroughLeicestershire LE113TUUnited Kingdom

Synthetic microporous membranes are increasingly used for energy-efficient and controlled production of micro-and nanoparticles and micro-and nanoemulsions with tuneable morphology and physico-chemical properties through various micromixing,emulsification,and evaporation *** emul-sification processes,the membrane pores are used for dispersed phase injection and size-controlled generation of droplets and droplet-templated *** micromixing processes,membrane is utilised as a micromixer for mixing two miscible liquids,usually solvent and antisolvent-rich solutions,which leads to the creation of supersaturation and subsequent nanoprecipitation or *** mem-brane evaporation processes,membrane is used to prevent phase dispersion while allowing efficient molecular diffusion of solvent and/or antisolvent vapour through gas-filled *** dispersion processes can be operated continuously by decoupling shear stress on the membrane surface from cross flow using tube insets,flow pulsations,swirling flow,membrane oscillations or membrane *** generation and solidification can be performed continuously in a single pass by connecting membrane module with a downstream *** dispersion processes can be used for pro-duction of nanoparticles such as nanovesicles(liposomes,micelles,ethosomes,and niosomes),nanogels,polymeric,lipid and metallic nanoparticles,and *** main advantages of membrane-assisted particle generation are in low energy consumption,controlled geometry and hydrodynamic conditions at the microscale level,flexible throughput due to modular and scalable design of membrane devices,and a wide choice of available microporous membranes with various wall porosities,wetta-bilities,pore sizes,and pore morphologies to suit different applications.

关键词： Nanoparticles Microparticles Nanoemulsions Microemulsions Microporous membrane Crystallisation Flash nanoprecipitation Emulsification Zero liquid discharge

Late Ordovician Mass Extinction: Earth, fire and ice

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National Science Review 2024年第1期11卷 51-65页

作者： David A.t.Harper Palaeoecosystems Group Department of Earth SciencesDurham University

the Late Ordovician Mass Extinction was the earliest of the ‘big’ five extinction events and the earliest to affect the trajectory of metazoan life. two phases have been identified near the start of the Hirnantian period and in the middle. It was a massive taxonomic extinction, a weak phylogenetic extinction and a relatively benign ecological extinction. A rapid cooling, triggering a major ice age that reduced the temperature of surface waters, prompted a drop in sea level of some 100 m and introduced toxic bottom waters onto the shelves. these symptoms of more fundamental planetary processes have been associated with a range of factors with an underlying driver identified as volcanicity. Volcanic eruptions, and other products, may have extended back in time to at least the Sandbian and early Katian, suggesting the extinctions were more protracted and influential than hitherto documented.

关键词： Ordovician LOME paleoecology palaeobiogeography biotas

Beta-lactam antibiotic resistance among Escherichia coli isolates from patients with urinary tract infections in Vietnam:A systematic review and meta-analysis

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Asian Pacific Journal of tropical Medicine 2024年第6期17卷 243-255,I0001-I0003页

作者： Dat t Nguyen Princess Margaret Cancer Centre University Health NetworkTorontoOntarioCanada

Objective:to investigate the evolving patterns of antimicrobial resistance against beta-lactam antibiotics in Escherichia coli isolates from urinary tract infection patients in Vietnam,covering the period from 2005 to ***:29 Descriptive studies published between 2010 and 2022 in English and Vietnamese were included in the *** on resistance rates to beta-lactam antibiotics,including cephalosporins and carbapenems,were extracted and *** pooled resistance rates were calculated using random-effects *** trends in resistance were assessed using linear regression ***:Among the beta-lactam antibiotics studied,Escherichia coli exhibited varying levels of resistance,with cephalosporins showing higher resistance rates compared to *** pooled resistance rates were 66%for cefotaxime,65%for ceftriaxone,54%for ceftazidime,and 56%for *** contrast,carbapenems demonstrated lower resistance rates,with weighted pooled resistance rates ranging from 3%to 4%for meropenem,ertapenem,and *** rates were also observed for amoxicillin/clavulanate(35%),ticarcillin/clavulanate(26%),and piperacillin/tazobactam(12%).Significant annual increases in resistance were noted for imipenem(0.56%,Pthis study highlights the critical issue of antimicrobial resistance in urinary tract infections in Vietnam and emphasizes the importance of prudent antibiotic use and the regular monitoring of resistance *** insights are useful for guiding healthcare professionals in optimizing treatment strategies and for policymakers in formulating evidence-based clinical guidelines to combat antibiotic resistance effectively.

关键词： Antimicrobial resistance Urinary tract infection Vietnam

A novel strategy for ionomer coating of Ag nanoparticles used for the electrochemical reduction of CO2 to CO in a membrane electrode assembly

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National Science Review 2024年第2期11卷 94-95页

作者： Alexis t.Bell Department of Chemical and Biomolecular Engineering University of California

the electrochemical reduction of the CO2reaction （CO2RR） offers an attractive means for converting the carbon content of CO2, released from a stationary source or the atmosphere, into fuels and chemicals [1]. Utiliz...

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A deep neural network based surrogate model for damage identification in full-scale structures with incomplete noisy measurements

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Frontiers of Structural and Civil Engineering 2024年第3期18卷 393-410页

作者： tram BUI-NGOC Duy-Khuong LY tam t tRUONG Chanachai tHONGCHOM t.NGUYEN-tHOI Laboratory for Computational Mechanics Institute for Computational Science and Artificial IntelligenceVan Lang UniversityHo Chi Minh City 70000Vietnam Faculty of Mechanical-Electrical and Computer Engineering School of TechnologyVan Lang UniversityHo Chi Minh City 70000Vietnam Faculty of Civil Engineering School of TechnologyVan Lang UniversityHo Chi Minh City 70000Vietnam Department of Computer Science Aarhus UniversityAarhus 8000Denmark thammasat University research unit in structural and foundation engineering Department of Civil EngineeringThammasat UniversityPathumthani 12120Thailand Laboratory for Applied and Industrial Mathematics Institute for Computational Science and Artificial IntelligenceVan Lang UniversityHo Chi Minh City 70000Vietnam thammasat School of Engineering Thammasat UniversityPathumthani 12120Thailand

the paper introduces a novel approach for detecting structural damage in full-scale structures using surrogate models generated from incomplete modal data and deep neural networks(DNNs).A significant challenge in this field is the limited availability of measurement data for full-scale structures,which is addressed in this paper by generating data sets using a reduced finite element(FE)model constructed by SAP2000 software and the MAtLAB programming *** surrogate models are trained using response data obtained from the monitored structure through a limited number of measurement *** proposed approach involves training a single surrogate model that can quickly predict the location and severity of damage for all potential *** achieve the most generalized surrogate model,the study explores different types of layers and hyperparameters of the training algorithm and employs state-of-the-art techniques to avoid overfitting and to accelerate the training *** approach’s effectiveness,efficiency,and applicability are demonstrated by two numerical *** study also verifies the robustness of the proposed approach on data sets with sparse and noisy measured ***,the proposed approach is a promising alternative to traditional approaches that rely on FE model updating and optimization algorithms,which can be computationally *** approach also shows potential for broader applications in structural damage detection.

关键词： vibration-based damage detection deep neural network full-scale structures finite element model updating noisy incomplete modal data