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Journal of Magnesium and Alloys 2024年第5期12卷 1841-1853页

作者： M.Lv h.L.Ge Q.Q.Jin X.h.Shao Y.T.Zhou B.Zhang X.L.Ma Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of Sciences72 Wenhua RoadShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China Materials Science and Engineering Research Center Guangxi University of Science and TechnologyLiuzhou 545006China

In-situ electron irradiation and aging are applied to introduce high-density precipitates in an Mg-10Gd-3Y-1Zn-0.5Zr(GWZ1031K,wt.%)alloy to improve the *** results show that the hardness of the Mg alloy after irradiation for 10 h and aging for 9 h at 250℃ is 1.64 GPa,which is approximately 64% higher than that of the samples before being *** is mainly attributed to γ'precipitates on the basal plane after irradiation and the high-density nanoscale β'precipitates on the prismatic plane after aging,which should be closely related to the irradiation-induced homogenous *** latter plays a key role in precipitation *** result paves a way to improve the mechanical properties of metallic materials by tailoring the precipitation through irradiation and aging.

关键词： Mg alloy Electron beam irradiation hardening Precipitates In-situ TEM

100 W-class green hydrogen production from ammonia at a dual-layer electrode containing a Pt-Ir catalyst for an alkaline electrolytic process

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Journal of Energy Chemistry 2024年第6期93卷 352-360,I0009页

作者： Donghyun Yoon Sunki Chung Minjun choi Eunhyeok Yang Jaeyoung Lee School of Earth Sciences and Environmental Engineering Gwangju Institute of Science and Technology(GIST)Gwangju 61005Republic of Korea International Future Research Center of Chemical Energy Storage and Conversion Processes GISTGwangju 61005Republic of Korea Ertl Center for Electrochemistry and Catalysis GISTGwangju 61005Republic of Korea TKG huchems Co.Ltd 963Sangam-roYeosu-siJeollanam-do 59614Republic of Korea

Ammonia allows storage and transport of hydrogen over long distances and is an attractive potential hydrogen *** decomposition has recently been used for the conversion of ammonia to hydrogen and is regarded as a future technology for production of CO_(2)-free pure ***,a heterostructural Pt-Ir dual-layer electrode is developed and shown to achieve successful long-term operation in an ammonia electrolyzer with an anion exchange membrane(AEM).This electrolyzer consisted of eight membra ne electrode assemblies(MEAs)with a total geometric area of 200 cm~2 on the anode side,which resulted in a hydrogen production rate of 25 L h~(-1).We observed the degradation in MEA performance attributed to changes in the anode catalyst layer during hydrogen production via ammonia ***,we demonstrated the relationship between the ammonia oxidation reaction(AOR)and the oxygen evolution reaction(OER).

关键词： Ammonia oxidation Dual-layer catalyst Green hydrogen Electrolytic process Oxygen evolution reaction

A high-Order Localized Artificial Diffusivity Scheme for Discontinuity Capturing on 1D Drift-Flux Models for Gas-Liquid Flows

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Advances in Applied Mathematics and Mechanics 2024年第1期16卷 47-74页

作者： Adyllyson h.Nascimento Eugenio S.Rosa Department of Energy School of Mechanical EngineeringUniversity of CampinasCampinasBrazil

A computational code is developed for the numerical solution of onedimensional transient gas-liquid flows using drift-flux models,in isothermal and also with phase change *** these two-phase models,classical upwind schemes such as Roe-and Godunov-type schemes are generally difficult to derive and expensive to use,since there are no treatable analytic expressions for the Jacobian matrix,eigenvalues and eigenvectors of the system of *** the other hand,the highorder compact finite difference scheme becomes an attractive alternative on these occasions,as it does not make use of any wave propagation information from the system of *** present paper extends the localized artificial diffusivity method for high-order compact finite difference schemes to solve two-phase flows with *** numerical method has simple formulation,straightforward implementation,low computational cost and,most importantly,*** numerical methodology proposed is validated by solving several numerical examples given in the *** simulations are sixth-order accurate and it is shown that the proposed numerical method provides accurate approximations of shock waves and contact *** is an essential property for simulations of realistic mass transport problems relevant to operations in the petroleum industry。

关键词： Compressible two-phase flows drift-flux model localized artificial diffusivity highorder numerical methods

Nonlinear boundary control problem of hyperbolic systems

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Journal of Control and Decision 2024年第1期11卷 73-83页

作者： A.Bouhamed A.El Kabouss h.Bouzahir ISTI Lab Ibn Zohr UniversityENSAAgadirMorocco Faculty of sciences Moulay Ismail UniversityMeknesMorocco

The paper is devoted to the study of optimal control of a hyperbolic system,where the control enters the system through the *** hyperbolic system is the wave equation on a smooth and open domain,where the boundary condition involves the normal derivative at the boundary of z,the time derivative of z times a constant k,and a nonlinear term ***,z is the state and u is the control,satisfying some boundedness condition depending on *** functional cost consists of the energy and the difference between the solution of the system at final time,and a desired state in *** a closed convex set,we prove the existence of an optimal control that minimises the cost functional using a priori ***,using the differentiability of the cost functional with respect to the control,we establish the characterisation by deriving necessary conditions that an optimal control must satisfy.A numerical approach is successfully illustrated by simulations.

关键词： Non-linear system hyperbolic system boundary control optimal control controllability

Implicit Function Based Open-loop Analysis Method for Detecting the SSR Using Identified System Parameters

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CSEE Journal of Power and Energy Systems 2024年第5期10卷 2016-2026页

作者： Luonan Qiu Tianhao Wen Yang Liu Q.h.Wu School of Electric Power Engineering South China University of TechnologyGuangzhou 510640China

This paper proposes an implicit function based open-loop analysis method to detect the subsynchronous resonance(SSR),including asymmetric subsynchronous modal attraction(ASSMA)and asymmetric subsynchronous modal repulsion(ASSMR),of doubly-fed induction generator based wind farms(DFIG-WFs)penetrated power *** some important parameters of DFIG-WF are difficult to obtain,reinforcement learning and least squares method are applied to identify those important *** predicting the location of closed-loop subsynchronous oscillation(SSO)modes based on the calculation of partial differentials of characteristic equation,both ASSMA and ASSMR can be *** proposed method in this paper can select SSO modes which move to the right half complex planes as control parameters ***,the proposed open-loop analysis method is adaptive to parameter *** studies are carried out on the 4-machine 11-bus power system to verify properties of the proposed method.

关键词： Open-loop modal analysis reinforcement learning based parameter identification subsynchronous resonance

Editorial for the Special Issue on Emerging Technology and Advanced Application of Nondestructive Detection for Power Equipment

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Chinese Journal of Electrical Engineering 2024年第1期10卷 1-2页

作者： Li J. Mei h. Li S. Tianjin University China Tsinghua Shenzhen International Graduate School China Lanzhou Jiaotong University China

The rapid development of clean and renewable energy technologies represented by wind and solar energy,as well as the continuous growth of load demand,have put forward higher requirements for the safe operation of the power *** performance of power equipment based on traditional dielectric materials is often limited by various defects generated during molding,transportation,assembly,and operation,which cannot meet the reliability requirements of power systems in the new *** detection is an essential technical method in industrial development,which can detect and evaluate the defect and damage status of in-service equipment,key components,and materials without damaging the object.

关键词： service Application operation

Viral and nonviral nanocarriers for in vivo CRISPR-based gene editing

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Nano Research 2024年第10期17卷 8904-8925页

作者： Zhongyuan Guo Audrey T.Zhu Ronnie h.Fang Liangfang Zhang Aiiso Yufeng Li Family Department of Chemical and Nano Engineering University of California San DiegoLa JollaCA 92093USA Division of host-Microbe Systems and Therapeutics Department of PediatricsUniversity of California San DiegoLa JollaCA 92093USA

The continued development of clustered regularly interspaced short palindromic repeats(CRISPR)technology has the potential to greatly impact clinical medicine,particularly for disease diagnosis and *** high demand for the in vivo delivery of CRISPR-based therapies,significant challenges *** include rapid degradation by enzymes,inefficient disease site targeting,and the risk of undesired off-target *** platforms,with their tailorable properties,have been engineered to efficiently package CRISPR payloads in various formats,including as plasmid DNA,mRNA,and ribonucleoprotein complexes,for in vivo *** them,recombinant adeno-associated viruses,virus-like particles,and lipid nanoparticles have displayed exceptional *** review will discuss the development of these and other nanocarriers for in vivo CRISPR-based genome editing.

关键词： clustered regularly interspaced short palindromic repeats(CRISPR) in vivo gene editing nanocarriers recombinant adeno-associated viruses(rAAVs) virus-like particle(VLP) lipid nanoparticle(LNP)

Expanding Annular Domain Algorithm to Estimate Domains of Attraction for Power System Stability Analysis

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CSEE Journal of Power and Energy Systems 2024年第5期10卷 1925-1934页

作者： Yuqing Lin Tianhao Wen Yang Liu Q.h.Wu School of Electric Power Engineering South China University of TechnologyGuangzhou 510640China

This paper presents an Expanding Annular Domain(EAD)algorithm combined with Sum of Squares(SOS)programming to estimate and maximize the domain of attraction(DA)of power *** proposed algorithm can systematically construct polynomial Lyapunov functions for power systems with transfer conductance and reliably determine a less conservative approximated DA,which are quite difficult to achieve with traditional *** linear SOS programming,we begin from an initial estimated DA,then enlarge it by iteratively determining a series of so-called annular domains of attraction,each of which is characterized by level sets of two successively obtained Lyapunov ***,the EAD algorithm is theoretically analyzed in detail and its validity and convergence are shown under certain *** the end,our method is tested on two classical power system cases and is demonstrated to be superior to existing methods in terms of computational speed and conservativeness of results.

关键词： Domain of attraction Lyapunov functions power system transient stability sum of squares programming

Evaluation of the coefficient of lateral stress at rest of granular materials under repetitive loading conditions

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第5期16卷 1709-1721页

作者： heerym han hyunwook Choo Junghee park Department of Civil and Environmental Engineering Hanyang UniversitySeoul04763South Korea Department of Civil and Environmental Engineering Incheon National UniversityIncheon22012South Korea

Although the internal stress state of soils can be affected by repetitive loading,there are few studies evaluating the lateral stress(or K_(0))of soils under repetitive *** study investigates the changes in K_(0) and directional shear wave velocity(V_(s))in samples of two granular materials with different particle shapes during repetitive loading.A modified oedometer cell equipped with bender elements and a diaphragm transducer was developed to measure the variations in the lateral stress and the shear wave velocity,under repetitive loading on the loading and unloading *** study produced the following results:(1)Repetitive loading on the loading path resulted in an increase in the K_(0) of test samples as a function of cyclic loading number(i),and(2)Repetitive loading on the unloading path resulted in a decrease in K_(0) according to *** shear wave velocity ratio(i.e.V_(s)(hh)/V_(s)(Vh),where the first and second letters in parentheses corresponds to the directions of wave propagation and particle motion,respectively,and V and h corresponds to the vertical and horizontal directions,respectively)according to i supports the experimental observations of this ***,when the tested material was in lightly over-consolidated state,there was an increase in K_(0) during repetitive loading,indicating that it was the initial K_(0),rather than the loading path,which is responsible for the change in K_(0).The power model can capture the variation in the K_(0) of samples according to ***,the K_(0)=1 line acts as the boundary between the increase and decrease in K_(0) under repetitive loading.

关键词： Coefficient of lateral stress at rest Repetitive loading Granular materials Shear wave velocity Stiffness anisotropy

Superplasticity of fine-grained Mg-10Li alloy prepared by severe plastic deformation and understanding its deformation mechanisms

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Journal of Magnesium and Alloys 2024年第1期12卷 316-331页

作者： h.T.Jeong S.W.Lee W.J.Kim Department of Materials Science and Engineering Hongik UniversityMapo-guSangsu-dong 72-1Seoul 121-791Republic of Korea

The superplastic behavior and associated deformation mechanisms of a fine-grained Mg-10.1 Li-0.8Al-0.6Zn alloy(LAZ1011)with a grain size of 3.2μm,primarily composed of the BCCβphase and a small amount of the hCPαphase,were examined in a temperature range of 473 K to 623 *** microstructural refinement of this alloy was achieved by employing high-ratio differential speed *** best superplasticity was achieved at 523 K and at strain rates of 10^(-4)-5×10^(-4)s^(-1),where tensile elongations of 550±600%were *** the heating and holding stage of the tensile samples prior to tensile loading,a significant increase in grain size was observed at temperatures above 573 ***,it was important to consider this effect when analyzing and understanding the superplastic deformation behavior and *** the investigated strain rate range,the superplastic flow at low strain rates was governed by lattice diffusion-controlled grain boundary sliding,while at high strain rates,lattice diffusion-controlled dislocation climb creep was the rate-controlling deformation *** was concluded that solute drag creep is unlikely to *** the late stages of deformation at 523 K,it was observed that grain boundary sliding led to the agglomeration of theαphase,resulting in significant strain *** mechanism maps were constructed forβ-Mg-Li alloys in the form of 2D and 3D formats as a function of strain rate,stress,temperature,and grain size,using the constitutive equations for various deformation mechanisms derived based on the data of the current tests.

关键词： Magnesium-lithium alloy Superplasticity Severe plastic deformation Grain size Grain growth