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Food Science and Human Wellness 2024年第4期13卷 2317-2326页

作者： Hang Gao Jian Zhang Li Liu Lijun Fu Yan zhao Germán Mazza Xin Zhang Beijing Academy of Food Sciences 100068 BeijingChina Institute for Research and Development in Process Engineering Biotechnology and Alternative Energies(PROBIENCONICET-UNCo)8300 NeuquénArgentina

Free amino acid(FAA)is the important component of vinegar that infl uences quality perception and consumer *** is one of the major metabolites produced by microorganisms;however,the microbial metabolic network on FAA biosynthesis remains *** metagenomic analysis,this work aimed to elucidate the roles of microbes in FAA biosynthesis during Monascus rice vinegar *** profiles from functional analyses showed 14 dominant genera with high contributions to the metabolism *** metabolic network for FAA biosynthesis was then constructed,and the microbial distribution in different metabolic pathways was *** results revealed that 5 functional genera were closely involved in FAA *** study illuminated the metabolic roles of microorganisms in FAA biosynthesis and provided crucial insights into the functional attributes of microbiota in vinegar fermentation.

关键词： Monascus rice vinegar Metagenomic analysis Free amino acid synthesis Metabolic pathway Microbial distribution

Giant Flexoelectric Effect in Snapping Surfaces Enhanced by Graded Stiffness

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Acta Mechanica Solida Sinica 2024年第4期37卷 528-540页

作者： Chuo zhao Department of Aeronautics Imperial College LondonSouth Kensington CampusLondonSW72AZUK

Flexoelectricity is present in nonuniformly deformed dielectric materials and has size-dependent properties, making it useful for microelectromechanical systems. Flexoelectricity is small compared to piezoelectricity;therefore, producing a large-scale flexoelectric effect is of great interest. In this paper, we explore a way to enhance the flexoelectric effect by utilizing the snap-through instability and a stiffness gradient present along the length of a curved dielectric plate. To analyze the effect of stiffness profiles on the plate, we employ numerical parameter continuation. Our analysis reveals a nonlinear relationship between the effective electromechanical coupling coefficient and the gradient of Young’s modulus. Moreover, we demonstrate that the quadratic profile is more advantageous than the linear profile. For a dielectric plate with a quadratic profile and a modulus gradient of − 0.9, the effective coefficient can reach as high as 15.74 pC/n, which is over three times the conventional coupling coefficient of piezoelectric material. This paper contributes to our understanding of the amplification of flexoelectric effects by harnessing snapping surfaces and stiffness gradient design.

关键词： Functionally graded material Flexoelectricity numerical continuation Snap-through instability

Recent developments in three-dimensional Zn metal anodes for battery applications

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InfoMat 2024年第1期6卷 1-30页

作者： Jianyu Chen Yizhou Wang Zhengnan Tian Jin zhao Yanwen Ma Husam n.Alshareef State Key Laboratory of Organic Electronics and Information Displays(KLOEID)and Jiangsu Key Laboratory for Biosensors Institute of Advanced Materials(IAM)Nanjing University of Posts&Telecommunications(NUPT)Nanjingthe People's Republic of China Materials Science and Engineering King Abdullah University of Science and Technology(KAUST)ThuwalSaudi Arabia Suzhou Vocational Institute of Industrial Technology Suzhouthe People's Republic of China

Aqueous zinc(Zn)ion batteries(AZIBs)are regarded as one of the promising candidates for next-generation electrochemical energy storage systems due to their low cost,high safety,and environmental ***,the commercialization of AZIBs has been severely restricted by the growth of dendrite at the Zn metal *** the planar-structured Zn anodes into threedimensional(3D)structures has proven to be an effective way to modulate the plating/stripping behavior of Zn anodes,resulting in the suppression of dendrite *** review provides an up-to-date review of 3D structured Zn metal anodes,including working principles,design,current status,and future *** aim to give the readers a comprehensive understanding of 3D-structured Zn anodes and their effective usage to enhance AZIB performance.

关键词： 3D metal anodes aqueous Zn ion batteries dendrite suppression Zn dendrite Zn metal anodes

Flat Zn deposition at battery anode via an ultrathin robust interlayer

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nano Research 2024年第9期17卷 8104-8111页

作者： Yizhou Wang Jianyu Chen Zibo Chen Qian He Zhengnan Tian Jin zhao Yanwen Ma Husam n.Alshareef Materials Science and Engineering King Abdullah University of Science and Technology(KAUST)Thuwal 23955-6900Saudi Arabia State Key Laboratory of Organic Electronics and Information Displays(KLOEID)and Jiangsu Key Laboratory for Biosensors Institute of Advanced Materials(IAM)Nanjing University of Posts and TelecommunicationsNanjing 210023China Suzhou Vocational Institute of Industrial Technology Suzhou 215104China

Rechargeable aqueous zinc(Zn)ion batteries(AZIBs)using low-cost and safe Zn metal anodes are considered promising candidates for future grid-scale energy storage systems,but the Zn dendrite problem severely hinders the further prospects of *** Zn depositing behaviors toward horizontal alignment is highly effective and thus has received huge ***,such a strategy is usually based on previous substrate engineering,which requires complex preparation or expensive ***,it is essential to develop a novel solution that can realize horizontally aligned Zn flake deposition via easy operation and low ***,we report an ultrathin and robust Kevlar membrane as the interlayer to mechanically suppress Zn dendrite *** to the randomly distributed flaky dendrites in the control group,the deposited Zn sheets would grow into parallel alignment with the existence of such *** the dendrites are effectively suppressed,Zn||Cu asymmetric,Zn||Zn symmetric,and Zn||MnO_(2)full batteries using Kevlar interlayer deliver significantly improved cycling ***,the Zn||MnO_(2)pouch cell using a Kevlar interlayer delivers stable cycling performance and shows stable operation during multi-angle *** believe this work provides a new possibility for regulating Zn deposition from a crystallographic perspective.

关键词： Zn metal anodes Zn dendrites aqueous Zn ion batteries dendrite suppression (002)crystal plane

Symmetry quantification and segmentation in STEM imaging through Zernike moments

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Chinese Physics B 2024年第8期33卷 39-48页

作者： Jiadong Dan Cheng Zhang 赵晓续 n.Duane Loh Department of Biological Sciences National University of SingaporeSingapore Center for Bioimaging Sciences(CBIS) National University of SingaporeSingapore Department of Physics National University of SingaporeSingapore School of Materials Science and Engineering Peking UniversityBeijing 100871China

We present a method using Zernike moments for quantifying rotational and reflectional symmetries in scanning transmission electron microscopy(STEM)images,aimed at improving structural analysis of materials at the atomic *** technique is effective against common imaging noises and is potentially suited for low-dose imaging and identifying quantum *** showcase its utility in the unsupervised segmentation of polytypes in a twisted bilayer TaS_(2),enabling accurate differentiation of structural phases and monitoring transitions caused by electron beam *** approach enhances the analysis of structural variations in crystalline materials,marking a notable advancement in the characterization of structures in materials science.

关键词： scanning transmission electron microscopy(STEM) symmetry segmentation

Hydrophobic long-chain two-dimensional perovskite scintillators for underwater X-ray imaging

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Rare Metals 2024年第1期43卷 175-185页

作者： Jin-Xiao Zheng Zi-An Zhou Tiao Feng Hui Li Cheng-Hua Sun nüWang Yang Tian Yong zhao Shu-Yun Zhou Key Laboratory of Photochemical Conversion and Optoelectronic Materials Technical Institute of Physics and ChemistryChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China Laboratory of Bioinspired Smart Interfacial Science and Technology of the Ministry of Education Beijing Key Laboratory of Bioinspired Energy Materials and DevicesSchool of ChemistryBeijing Advanced Innovation Center for Biomedical EngineeringBeihang UniversityBeijing 100191China Department of Engineering Physics Tsinghua University and Key Laboratory of Particle and Radiation Imaging Ministry of EducationTsinghua UniversityBeijing 100084China e-mail:yangt@***

The underwater X-ray imaging technology development is significant to subaqueous target reconnaissance/detection/identification, subfluvial archaeology,submerged resource exploration, etc. As the core of X-ray imaging detection, the scintillator has been plagued by inherent moisture absorption and decomposition, and strict requirements for seamless packaging and ***, we designed a manganese-doped two-dimensional(2D) perovskite scintillator modified by hydrophobic longchain organic amine through the combination of component and doping engineering. The modified perovskites show high water repellency that can be used as an underwater X-ray scintillator. X-ray images of aquatic organisms or other objects with a high spatial resolution of10 lp·mm^(-1) at a big view field(32 mm × 32 mm) were obtained by scintillation screen. This hydrophobic perovskite scintillator based on molecular design is of great promise in underwater X-ray nondestructive testing technology development.

关键词： Two-dimensional perovskite Hydrophobic Scintillators Underwater X-ray imaging Underwater nondestructive testing technology

Frequency Domain Fatigue Evaluation on SCR Girth-Weld Based on Structural Stress

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China Ocean Engineering 2024年第2期38卷 255-270页

作者： ZHAnG Long zhao Tian-feng College of Safety and Ocean Engineering China University of Petroleum(Beijing)Beijing 102249China

The Steel Catenary Riser(SCR)is a vital component for transporting oil and gas from the seabed to the floating *** harsh environmental conditions and complex platform motion make the SCR’s girth-weld prone to fatigue *** structural stress fatigue theory and Master S-n curve method provide accurate predictions for the fatigue damage on the welded joints,which demonstrate significant potential and compatibility in multi-axial and random fatigue ***,we propose a new frequency fatigue model subjected to welded joints of SCR under multiaxial stress,which fully integrates the mesh-insensitive structural stress and frequency domain random process and transforms the conventional welding fatigue technique of SCR into a spectrum analysis technique utilizing structural ***,a full-scale FE model of SCR with welds is established to obtain the modal structural stress of the girth weld and the frequency response function(FRF)of modal coordinate,and a biaxial fatigue evaluation about the girth weld of the SCR can be achieved by taking the effects of multi-load correlation and pipe-soil interaction into *** research results indicate that the frequency-domain fatigue results are aligned with the time-domain results,meeting the fatigue evaluation requirements of the SCR.

关键词： SCR girth weld random vibration self(cross)power spectrum structural stress method biaxial fatigue damage

Tribological properties of low-temperature time-dependent pretreated graphite for mechanical seal pairs in high-speed turbopump

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Friction 2024年第2期12卷 305-318页

作者： Yangyang zhao Guoyuan ZHAnG Junqian WAnG He WAnG Weigang zhao Qunfeng ZEnG School of Mechano-Electronic Engineering Xidian UniversityXi’an 710071China Xi’an Aerospace Propulsion Institute Xi’an 710071China Key Laboratory of Education Ministry for Modern Design and Rotor-Bearing System Xi’an Jiaotong UniversityXi’an 710049China

The friction coefficient and wear rate of pretreated graphite with liquid nitrogen were obtained by using a ball-on-disk tester,and the wear of GCr15–graphite seal pairs with the low-temperature time-dependent pretreatment was discussed by comparing the wear *** results show that liquid nitrogen pretreatment can affect the hardness and interlayer spacing of *** range of the friction coefficients of pretreated graphite changes from 0.17 to *** the increase of liquid nitrogen pretreatment time,the wear mechanism of graphite would change from dominated three-body wear to adhesion *** experimental results of the mechanical seal with liquid nitrogen pretreatment show that the wear rate of stator is less than 0.00165 mm^(3)·n^(−1)·m^(−1),and the graphite shows a good low-temperature compatibility.

关键词： graphite low-temperature pretreatment mechanical seal friction and wear

Dynamic response of water-rich tunnel subjected to plane P wave considering excavation induced damage zone

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Underground Space 2024年第2期15卷 113-130页

作者： Gongliang Xiang Ming Tao Rui zhao Huatao zhao Muhammad Burhan Memon Chengqing Wu School of Resources and Safety Engineering Central South UniversityChangsha 410083China School of Geoscience and Technology Southwest Petroleum UniversityChengdu 610500China School of Civil and Environmental Engineering University of Technology SydneyNSW 2007Australia

The stability analysis of a deep buried tunnel subjected to dynamic disturbance is an important *** this study,the transient response has been obtained by establishing a water-rich tunnel model considering excavation damage zone(EDZ).Based on Biot’s two-phase dynamic theory and wave function expansion method,the analytical solution of dynamic response around the water-rich tunnel containing EDZ subjected to P wave is ***,Fourier transform and Duhamel’s integral technique is introduced to calculate the transient response,and the equivalent blasting curve is adopted to input excitation *** dimensionless parameters thickness n and shear modulus ratio lare defined to characterize the degree of damage in the surrounding rock,investigating the influencing factors,such as the parameters and the incident source *** results indicate that the dynamic stress concentration factor(DSCF)gradually decreases as the dimensionless parameters ***,it is observed that the DSCF is more sensitive to changes in the thickness parameter ***,the influence of the waveform parameters has been taken into account in the analysis of transient response,and the stress state and transfer process in each time stage of the EDZ are *** study establishes a theoretical foundation for comprehending the mechanical behavior and support design considerations associated with a deep-buried water-rich tunnel containing EDZ.

关键词： Water-rich tunnel Two-phase dynamic theory Wave scattering Transient response Dynamic stress concentration

Optimization of mixing speed and time to disperse the composite conductive agent composed of carbon black and graphene in lithium-ion battery slurry

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Particuology 2024年第9期92卷 1-12页

作者： Zhilong Wang Jialong Tu Xinhao Yu Feixiang Li Zhenzhen zhao Yahui Cui Tong zhao Faculty of Mechanical and Precision Instrument Engineering Xi'an University of TechnologyXi'an710048China

This paper proposed an optimal approach to disperse the composite conductive agent which is composed of carbon black(CB)and graphene(Gr)within lithium-ion battery(LIB)slurry with different mixing speeds and mixing *** internal structures of LIB slurry are characterized by Electrochemical Impedance Spectroscopy,Scanning Electron Microscopy,and Raman ***,a composite conductive solution is prepared by mixing the composite conductive agent with nMP solvent under the conditions of five different mixing speeds n_(1)(n_(1)=1000,1100,1200,1300,1400 rpm)in the case of mixing time t_(1)=10 ***,LIB slurry is prepared by blending the composite conductive solution,LiCoO_(2)and PVDF-nMP solution under the conditions of five different mixing speeds n_(2)(n_(2)=1000±280,1100±280,1200±280,1300±280,1400±280 rpm)in the case of mixing time t_(2)=6 *** analyzing the internal structure of different LIB slurries,it shows that in the case of n_(1)=n_(2)=1200 rpm,a conductive network structure is well formed within LIB ***,in order to determine the optimal time to prepare the composite conductive solution for LIB slurry,nine different t_(1)(t_(1)=0,10,20,30,40,50,60,70,80 min)are *** analyzing the internal structure of different LIB slurries,a well-formed conductive network structure and a uniformly distributed composite conductive agent are deduced in LIB slurry when t_(1)=50 ***,it can be concluded that the composite conductive agent composed of CB and Gr is able to be uniformly dispersed in LIB slurry by establishing a well-formed conductive network structure under the optimal mixing speed n_(1)=n_(2)=1200 rpm and the optimal mixing time t_(1)=50 min,t_(2)=6 *** kind of the internal structure has the potential to be used to further analyze the dispersion characterizations of LIB slurry under different composite conductive agent and CB/Gr ratios with the aim of improving the final performance of LIB.

关键词： Lithium-ion battery slurry Composite conductive agent Carbon black Graphene