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Acta Metallurgica Sinica(English Letters) 2024年第2期37卷 339-352页

作者： yang Feng Wenhuan Chen Zheng xu Weijun He Bin Jiang Fusheng Pan College of Materials Science and Engineering Chongqing UniversityChongqing400044China International Joint Laboratory for Light Alloys(Ministry of Education) Chongqing UniversityChongqing400044China

AZ31/Mg3y composites with a layer thickness of 100-200μm were fabricated by accumulated rolling bonding(ARB),which was followed by diffusion annealing at 300℃ for 0-32 *** interface layer,containing numerous Al-y precipitates,is formed in the Mg3y layer that is adjacent to the interface as a result of Al diffusing from the AZ31 layers into the Mg3y *** thickness of the interface layer gets increased and more precipitates are formed in the interface layer with the extension of the annealing *** microhardness of the AZ31 and Mg3y layer decreases firstly and then reaches a stable value,while the microhardness of the interface layer increases gradually with the extension of the annealing *** AZ31/Mg3y composites exhibit equivalent strength but increased ductility after diffusion annealing,in comparison to the as-rolled AZ31/Mg3y *** addition,the AZ31/Mg3y composites after annealing always present higher strength and ductility than AZ31/AZ31 composite,which was fabricated by the same process as that for the AZ31/Mg3y ***-deformation induced strengthening also plays an important role in the excellent strength and ductility of the annealed AZ31/Mg3y *** study can provide a direction for improving the plasticity and strength of magnesium alloys synergistically.

关键词： AZ31/Mg3y composite Accumulated rolling bonding Diffusion annealing Precipitates Strengthening

Excess non-COVID-19-related mortality among inflammatory bowel disease decedents during the COVID-19 pandemic

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World Journal of Gastroenterology 2024年第20期30卷 2677-2688页

作者： Sarah Rotondo-Trivette Xin-yuan He Jamil S Samaan Fan Lv Emily Truong Michaela Juels Anthony Nguyen xu Gao Jian Zu yee Hui yeo Fan-Pu Ji Gil y Melmed Department of Medicine Cedars-Sinai Medical CenterLos AngelesCA 90048United States Department of Infectious Disease The Second Affiliated Hospital of Xi’an Jiaotong UniversityXi’an 710004Shaanxi ProvinceChina Karsh Division of Gastroenterology and Hepatology Department of Medicine Cedars-Sinai Medical CenterLos AngelesCA 90048United States School of Mathematics and Statistics Xi’an Jiaotong UniversityXi’an 710049Shaanxi ProvinceChina David Geffen School of Medicine University of CaliforniaLos AngelesLos AngelesCA 90095United States Division of Gastroenterology The Second Affiliated Hospital of Xi’an Jiaotong UniversityXi’an 710004Shaanxi ProvinceChina National and Local Joint Engineering Research Center of Biodiagnosis and Biotherapy The Second Affiliated Hospital of Xi’an Jiaotong UniversityXi’an 710004Shaanxi ProvinceChina Key Laboratory of Surgical Critical Care and Life Support(Xi’an Jiaotong University) Ministry of EducationXi’an 710004Shaanxi ProvinceChina

BACKGROUND The coronavirus disease 2019(COVID-19)pandemic disrupted healthcare in the United *** To investigate COVID-19-related and non-COVID-19-related death and characteristics associated with excess death among inflammatory bowel disease(IBD)*** We performed a register-based study using data from the National Vital Statistics System,which reports death data from over 99%of the United States population,from January 1,2006 through December 31,***-related deaths among adults 25 years and older were stratified by age,sex,race/ethnicity,place of death,and primary cause of *** and actual age-standardized mortality rates(ASMRs)per 100000 persons were *** 49782 IBD-related deaths occurred during the study ***-COVID-19-related deaths increased by 13.14%in 2020 and 18.12%in 2021[2020 ASMR:1.55 actual vs 1.37 predicted,95%confidence interval(CI):1.26-1.49;2021 ASMR:1.63 actual vs 1.38 predicted,95%CI:1.26-1.49].In 2020,non-COVID-19-related mortality increased by 17.65%in ulcerative colitis(UC)patients between the ages of 25 and 65 and 36.36%in non-Hispanic black(NHB)Crohn’s disease(CD)*** the pandemic,deaths at home or on arrival and at medical facilities as well as deaths due to neoplasms also *** IBD patients suffered excess non-COVID-19-related death during the *** death was associated with younger age among UC patients,and with NHB race among CD *** death at home or on arrival and due to neoplasms suggests that delayed presentation and difficulty accessing healthcare may have led to increased IBD mortality.

关键词： Inflammatory bowel disease Ulcerative colitis Crohn’s disease COVID-19 Excess death Race Sex Disparities

Study of the Ballistic Impact Behavior of Protective Multi-Layer Composite Armor

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Computer Modeling in Engineering & Sciences 2024年第7期140卷 171-199页

作者： Dongsheng Jia yingjie xu Liangdi Wang Jihong Zhu Weihong Zhang State IJR Center of Aerospace Design and Additive Manufacturing Northwestern Polytechnical UniversityXi’an710072China

The abalone shell,a composite material whose cross-section is composed of inorganic and organic layers,has high strength and *** by the abalone shell,several multi-layer composite plates with different layer sequences and thicknesses are studied as bullet-proof material in this *** investigate the ballistic performance of this multi-layer structure,the complete characterization model and related material parameters of large deformation,failure and fracture ofAl_(2)O_(3)ceramics andCarbon Fiber Reinforced Polymer(CFRP)are ***,3D finite element models of the proposed composite plates with different layer sequences and thicknesses impacted by a 12.7 mm armor-piercing incendiary(API)are built using Abaqus to predict *** simulation results show that the CFRP/Al2O3 ceramic/Ultrahigh Molecular Weight Polyethylene(UHMWPE)/CFRP(1 mm/4 mm/4 mm/1 mm)composite is the optimized stack of *** simulation results under specified layer sequence and thickness have a reasonable correlation with the experimental results and reflect the failure and fracture of the multi-layer composite protective armor.

关键词： Protective armor composite bionic design structure design mechanical property

General synthesis of transition metal nitride arrays by ultrafast flash Joule heating within 500 ms

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Science China Chemistry 2024年第6期67卷 1976-1982页

作者： Peiqi Shen Jiahui Zhao yanan Gao yunxiang Lin yuchen Han Kun xu School of Chemistry and Chemical Engineering Key Laboratory of Functional Inorganic Material Chemistry of Anhui ProvinceAnhui Province Key Laboratory of Chemistry for Inorganic/Organic Hybrid Functionalized MaterialsKey Laboratory of Structure and Functional Regulation of Hybrid Materials of Ministry of EducationAnhui UniversityHefei230601China Institutes of Physical Science and Information Technology Center of Free Electron Laser&High Magnetic FieldLeibniz International Joint Research Center of Materials Sciences of Anhui ProvinceAnhui UniversityHefei230601China

Transition metal nitrides(TMNs)are considered as viable alternatives to noble metal catalysts owing to their versatile electronic structure and favorable catalytic ***,the conventional synthetic processes for TMNs suffer from high energy consumption and low production *** this study,a range of TMNs and their hetero-composite arrays were successfully synthesized via an ultrafast flash Joule heating technology within 0.5 *** a proof concept,the nitrides and hetero-composites were applied for the electrocatalytic hydrazine oxidation reaction(HzOR),in which the Co_(4)N/Mo_(16)N_(7)arrays shows the best performance with a geometric current density of 100 mA cm^(-2)at 23 mV(*** hydrogen electrode(RHE)).This work paves a new way for the ultrafast synthesis of TMNs which could meet the ever-increased energy crisis.

关键词： flash Joule heating rapid synthesis transition metal nitrides hydrazine oxidation reaction electrocatalysts

A calibration and compensation method for an industrial robot with high accuracy harmonic reducers

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Science China(Technological Sciences) 2024年第3期67卷 725-739页

作者： ZHAO yiyang LIU xun CAO JiaBin LIU Jinyu xu yan yAN WeiXin School of Mechanical Engineering Shanghai Jiao Tong UniversityShanghai 200240China College of Computer and Control Engineering Northeast Forestry UniversityHarbin 150040China

Industrial serial robots need high stiffness to keep absolute pose accuracy and meet the requirements in practical applications. However, the weak stiffness feature of robot joints and the payloads affected on robot end-effector, which will also increase the pose error of robot. Especially, the existing calibration methods often consider under no-payload condition without discussing the payload state. In this paper, we report a new industrial serial robot composed by a new harmonic reducer: Model-y, based on high accuracy and high stiffness, and a kinematic parameter calibration algorithm which is based on a harmonic reducer forcedeformation model. To decrease the accuracy effects of payload, an iterative calibration method for kinematic parameters with payload situation was proposed. Simulation and experiments are conducted to verify the effectiveness of the proposed calibration method using the self-developed industrial serial robot. The results show a remarkably improved accuracy in absolute position and orientation with the robot's payload range. The position mean error has 70% decreased to 0.1 mm and the orientation mean error diminished to less than 0.01° after calibration with compensation. Additionally, online linear and circular tests are carried out to evaluate the position error of the robot during large-scale spatial and low-speed continuous movement. The accuracy is consistent with the previous calibration results, indicating the effectiveness and advantages of the proposed strategy in this article.

关键词： industrial serial robot Model-y harmonic calibration stiffness model online compensation

Single-structure 3-axis Lorentz force magnetometer based on an AlN-on-Si MEMS resonator

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Microsystems & Nanoengineering 2024年第3期10卷 75-86页

作者： Cheng Tu xu-heng Ou-yang ying-jie Wu Xiao-sheng Zhang School of Integrated Circuit Science and Engineering University of Electronic Science and Technology of ChinaChengdu 611731China

This work presents a single-structure 3-axis Lorentz force magnetometer(LFM)based on an AlN-on-Si MEMS *** operation of the proposed LFM relies on the flexible manipulation of applied excitation currents in different directions and frequencies,enabling the effective actuation of two mechanical vibration modes in a single device for magnetic field measurements in three ***,the excited out-of-plane drum-like mode at 277 kHz is used for measuring the x-and y-axis magnetic fields,while the in-plane square-extensional mode at 5.4 MHz is used for measuring the z-axis magnetic *** different configurations of applied excitation currents ensure good crossinterference immunity among the three *** to conventional capacitive LFMs,the proposed piezoelectric LFM utilizes strong electromechanical coupling from the AlN layer,which allows it to operate at ambient pressure with a high *** understand and analyze the measured results,a novel equivalent circuit model for the proposed LFM is also reported in this work,which serves to separate the effect of Lorentz force from the unwanted capacitive *** demonstrated 3-axis LFM exhibits measured magnetic responsivities of 1.74 ppm/mT,1.83 ppm/mT and 6.75 ppm/mT in the x-,y-and z-axes,respectively,which are comparable to their capacitive counterparts.

关键词： resonator Lorentz structure

Naturally Crosslinked Biocompatible Carbonaceous Liquid Metal Aqueous Ink Printing Wearable Electronics for Multi-Sensing and Energy Harvesting

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Nano-Micro Letters 2024年第8期16卷 148-168页

作者： King yan Chung Bingang xu Di Tan Qingjun yang Zihua Li Hong Fu Nanotechnology Center School of Fashion and TextilesThe Hong Kong Polytechnic UniversityHong Kong 999077People’s Republic of China Department of Mathematics and Information Technology The Education University of Hong KongHong KongPeople’s Republic of China

Achieving flexible electronics with comfort and durability comparable to traditional textiles is one of the ultimate pursuits of smart *** printing is desirable for e-textile development using a simple and inexpensive ***,fabricating high-performance atop textiles with good dispersity,stability,biocompatibility,and wearability for high-resolution,large-scale manufacturing,and practical applications has remained ***,waterbased multi-walled carbon nanotubes(MWCNTs)-decorated liquid metal(LM)inks are proposed with carbonaceous gallium–indium *** the assistance of biopolymers,the sodium alginate-encapsulated LM droplets contain high carboxyl groups which non-covalently crosslink with silk sericin-mediated MWCNTs.E-textile can be prepared subsequently via printing technique and natural waterproof triboelectric coating,enabling good flexibility,hydrophilicity,breathability,wearability,biocompatibility,conductivity,stability,and excellent versatility,without any artificial *** obtained e-textile can be used in various applications with designable patterns and ***-sensing applications of recognizing complex human motions,breathing,phonation,and pressure distribution are demonstrated with repeatable and reliable ***-powered and energy-harvesting capabilities are also presented by driving electronic devices and lighting *** proof of concept,this work provides new opportunities in a scalable and sustainable way to develop novel wearable electronics and smart clothing for future commercial applications.

关键词： Biocompatible Conductive ink Biopolymer E-textile Carbonaceous liquid metal

An investigation on topologies of hybrid manifold,impinging-jet nozzle and micro-pin-fin heat sinks

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Science China(Technological Sciences) 2024年第4期67卷 1061-1076页

作者： SHI QianLei yAO XiaoLe LIU Qian QIN Le JU Xing xu Chao Key Laboratory of Power Station Energy Transfer Conversion and System of MOE North China Electric Power UniversityBeijing 102206China

The hybrid manifold micro-pin-fin(MMPF)heat sink combined nozzle jets is an option for large-scale integrated circuits(LSI).The demond for uniform and ultra-high heat flux removal by MMPF heat sink has not been adequately *** work aims to solve the problem of fluid *** proposed basic tiling topologies,including square,regular hexagon,30°rhombus,and 60°rhombus topologies,provide different organized fluid flows and heat transfer *** present study focuses on comparing these topologies according to independent porous medium parameters,such as nozzle pore size D_(Z),flow pore size D_(X,y),and porosityε.The results show that the square topology achieves the smallest total thermal resistance R_(tot)value of0.0975×10^(-4)K m^2/W,while the hexagon topology achieved the highest value of COP/?T,which was 2033.9 K^(-1).According to the sensitivity analysis results,the optimal total thermal resistance can be obtained by balancing the influences of nozzle pore size,flow pore size,and *** optimal pressure drop can be obtained by maximizing the porosity.

关键词： heat sink ultra-high heat flux manifold micro-pin-fin impinging-jet topology

Immediate implantation of ultrafine fiber slow-release system based on cell electrospinning to induce osteogenesis of mesenchymal stem cells

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Regenerative Biomaterials 2024年第2期3卷 76-87页

作者： Tao Lu Long yang Zhuoyang Li yin Liu Shun'en xu Chuan ye Department of Orthopaedics The Affliated Hospital of Guizhou Medical UniversityGuiyang 550004China Department of Orthopaedics The First People's Hospital of GuiyangGuiyang 550004China Center for Tissue Engineering and Stem Cell Research Guizhou Medical UniversityGuiyang 550004China Department of Otolaryngology Head and Neck Surgery Xinqiao HospitalArmy Medical University(Third Military Medical University)Chongqing 400037China Department of Dental implant Stomatological Hospital of GuiyangGuiyang 550000China

This study presents the development and evaluation of a poly(3-hydroxybutyrate-co-4-hydroxybutyrate)(P34HB)ultrafine fiber slow-release system for in vivo osteogenic induction of human umbilical cord mesenchymal stem cells(HUCMSCs).Utilizing dual-nozzle and cell electrospinning techniques,the system encapsulates L-ascorbic acid-2-phosphate magnesium(AsP),βB-glycerophosphate sodium and dexamethasone(DEX)within the'fbers,ensuring sustained osteogenic *** scaffold's morphology,characterization,hydrophilicity,mechanical properties and cellular behavior were *** subcutaneous implantation in rabbits was con-ducted to observe its ectopic osteogenic induction *** fabricated P34HB ultrafine fiber slow-release *** ization *** distribution of HUCMSCs and inducing components within the scaffold,with no chemical reactions affecting the active *** vitro tests showcased a prolonged release of DEX and ASP,while biocompatibility assays highlighted the scaffold's suitability for cellular *** Red,type I collagen,and osteopontin(OPN)staining verifed the scaffold's potent osteogenic induction effect on ***,immediate implantation into New Zealand White rabbits led to significant new bone formation within 8 *** findings underscore the system's potential for immediate in vivo implantation without prior in vitro induction,marking a promising advancement in bone tissue engineering.

关键词： bone tissue engineering cell electrospinning in vivo induction immediate implantation biomaterials

Impurity formation mechanism of silicon carbide crystals smelted by Acheson process

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Journal of Iron and Steel Research International 2024年第6期31卷 1367-1375页

作者： Dong Feng Hong-qiang Ru xu-dong Luo Jie-gang you Ling Zhang School of Materials and Metallurgy University of Science and Technology LiaoningAnshan 114051LiaoningChina Key Laboratory for Anisotropy and Texture of Materials(Ministry of Education) Institute of Advanced CeramicsSchool of Materials Science and EngineeringNortheastern UniversityShenyang 110819LiaoningChina Liaoning Institute of Science and Technology Benxi 117004LiaoningChina

In order to further promote the application of SiC refractories in modern steel metallurgy,the occurrence forms and formation mechanism of impurities in SiC crystals smelted by Acheson process were *** techniques of inductively coupled plasma-atomic emission spectrometry,X-ray diffraction,and scanning electron microscopy were combined to examine the types and occurrence forms of impurities in smelted SiC *** results showed that the main impurities in the SiC are free Si,free C,oxides(CaO·Al_(2)O_(3)·2SiO_(2),3Al_(2)O_(3)·2SiO_(2),CaO·SiO_(2) and SiO_(2))and alloy phases(Fe_(x)Si_(y),Fe_(x)Si_(y)Ti_(z) and Fe_(x)Al_(y)Si_(z)).The formation process of impurities during the smelting of SiC can be described as follows:At high temperature,the SiO_(2) and Fe,Ti related oxide impurities present in the raw materials are reduced to Si,Fe,and Ti metal *** the reduction process,the free Si,Fe_(x)Si_(y) and Fe_(x)Si_(y)Ti_(z) are precipitated from the melt during *** Si primarily exists in aggregated form within the SiC crystal,while the alloy phase is predominantly found at the interface between SiC and free Si,with Fe_(x)Si_(y)Ti_(z) embedded within *** the end of the cooling process,other impurity oxides such as Al_(2)O_(3),CaO,and some unreduced SiO_(2) solidify to form calcium-aluminum-silicate glass phases,predominantly located between SiC *** remaining C from the reaction is mainly dispersed as free C within the SiC crystal and at the interface between SiC and free Si.

关键词： Impurity element Formation mechanism Smelted SiC crystal SiC refractory Occurrence form