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Journal of Advanced Dielectrics 2020年第4期10卷 13-21页

作者： Nguyen Truong-Tho le dai vuong Department of Physics College of Sciences Hue UniversityHue CityVietnam Faculty of Natural Sciences Thu Dau Mot University Binh Duong Province Vietnam

Sintered lead-free Bi_(0.5)(Na_(0.8)K_(0.2)T_(0.5)(Ti0:96Sn0:04TO_(3)ceramics(BNKTS)have been fabricated via a solid-state *** effect of sintering temperature on the structural,morphological,dielectric,ferroelectric and energy storage properties of BNKTS ceramics was investigated,and it was found that the electrical properties of the synthesized ceramics increased with the increase in the sintering temperature,and the highest values were achieved at 1100℃.The ceramics sintered at the optimized temperature of 1100℃exhibited the best physical,dielectric,ferroelectric and energy storage properties,namely,high density(the relative density,ρ=5:88 ***^(-3),approximate to 96.7%of the theoretical value),high densification factor(DF=0:93),high dielectric constant(ε_(r)=1215),low dielectric loss(tanδ=0:051),highest dielectric constant(ε_(max)=4335),high remanent polarization(Pr=9:5μ***^(-2),high coercive field(E_(c)=14:3 kV/cm),high energy storage density(0.12 J/cm^(3),and high energy storage efficiency(41.7%at 46.3 kV/cm).

关键词： lead-free ceramics BNKT sintering temperature dielectric constant

Structure and Electrical Properties of Fe<sub>2</sub>O<sub>3</sub>-Doped PZT-PZN-PMnN Ceramics

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Journal of Modern Physics 2014年第14期5卷 1258-1263页

作者： le dai vuong Phan Dinh Gio Department of Physics College of Sciences Hue University Hue City Vietnam

The 0.8Pb(Zr0.48Ti0.52)O3 – 0.125Pb(Zn1/3Nb2/3)O3 – 0.075Pb(Mn1/3Nb2/3)O3 + x wt% Fe2O3 ceramics (PZT-PZN-PMnN), where x = 0 ÷?0.35, has been prepared by two-stage calcination method. The effect of Fe2O3 content on the crystal structure and electrical properties of ceramics has been investigated. The results of X-ray diffraction (XRD) show that all samples have pure perovskite phase with tetragonal structure, the c/a ratio increases with increasing Fe2O3 content. At x = 0.25, electrical properties of ceramics are best: the density (r) of 7.86 g/cm3, the electromechanical coupling factor (kp) of 0.64, the dielectric constant (εr) of 1400, the dielectric loss (tand) of 0.003, the mechanical quality factor (Qm) of 1450, the piezoelectric constant (d31) of 155 pC/N, and the remanent polarization (Pr) of 37 μC/cm2, which makes it as a promising material for high power piezoelectric devices.

关键词： Crystal Structure Dielectrics Piezoelectrics Electromechanical Coupling Factor Fe2O3 Doping

Electrical Properties of CuO-Doped PZT-PZN-PMnN Piezoelectric Ceramics Sintered at Low Temperature

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Journal of Materials Science and Chemical Engineering 2014年第11期2卷 20-27页

作者： Phan Dinh Gio le dai vuong Ho Thi Thanh Hoa Department of Physics College of Sciences Hu&ecirc University Hu&ecirc Vietnam Faculty of Chemical and Environmental Engineering Hu&ecirc Industry College Hu&ecirc Vietnam

The 0.8Pb(Zr0.48Ti0.52)O3-0.125Pb(Zn1/3Nb2/3)O3-0.075Pb(Mn1/3Nb2/3)O3 (PZT-PZN-PMnN) + x wt% CuO piezoelectric ceramics, where x = 0.0, 0.05, 0.075, 0.10, 0.125, 0.150, and 0.175, have been fabricated by the conventional solid-state reaction method and the B-site Oxide mixing technique (BO). The effect of CuO on the sinterability, structure, and electrical properties of PZT-PZN-PMnN ceramics was systematically studied. The CuO addition significantly reduced the sintering temperature of the ceramics from 1150°C to 850°C. Experimental results showed that with the doping of CuO, all the ceramics could be well sintered and exhibit a dense, pure perovskite structure. The specimen containing 0.125 wt% CuO sintered at 850°C showed the good electrical properties: the density of 7.91 g/cm3;the electromechanical coupling factor, kp = 0.55 and kt = 0.46;the dielectric constant, ε = 1179;the dielectric loss (tand) of 0.006;the mechanical quality factor (Qm) of 1174;the piezoelectric constant (d31) of 112 pC/N.

关键词： Crystal Structure Dielectric Piezoelectric Constant Mechanical Quality Factor

Influence of sintering behavior on the microstructure and electrical properties of BaTiO_(3) lead-free ceramics from hydrothermal synthesized precursor nanoparticles

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Journal of Advanced Dielectrics 2021年第2期11卷 42-51页

作者： Do Viet On le dai vuong Truong Van Chuong Dao Anh Quang Ho Van Tuyen Vo Thanh Tung Department of Physics College of Sciences Hue UniversityHue CityVietnam Faculty of Chemical and Environmental Engineering Hue Industrial College Hue CityVietnam Institute of Research and Development Duy Tan University Da Nang CityVietnam Faculty of Natural Sciences Duy Tan University Da Nang CityVietnam

BaTiO_(3) nanoparticles were synthesized by hydrothermal method using amorphous phase TiO_(2) precursor as the *** microstructure and phase structure were determined using XRD,SEM and Raman spectroscopy analysis *** results showed that BaTiO_(3) nanoparticles have tetragonal structure,average size of about 100 nm was obtained at Ba/Ti ratio of 1.5,synthesis temperature of 200℃ and reaction time of 12 *** components of the BaTiO_(3) lead-free ceramic system are fabricated by conventional solid-phase reaction from the average size BaTiO_(3) particles about 100 nm obtained by hydrothermal *** effects of sintering behavior on dielectric,ferroelectric and piezoelectric properties of BT high-density ceramic were *** BaTiO_(3) ceramic composition sintered at 1300℃ has a relative density of 97%,the value of the electromechanical coefficient kp=0.40,k33=0.42,the large piezoelectric coefficient d_(33)=300 pC/N,d_(31)=−125 pC/N.

关键词： BaTiO_(3)nanoparticles lead-free ceramics piezoelectric ferroelectric properties

Research status and prospects of the fractal analysis of metal material surfaces and interfaces

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 20-38页

作者： Qinjin dai Xuefeng Liu Xin Ma Shaojie Tian Qinghe Cui Beijing Advanced Innovation Center for Materials Genome Engineering University of Science and Technology BeijingBeijing 100083China Beijing Laboratory of Metallic Materials and Processing for Modern Transportation University of Science and Technology BeijingBeijing 100083China Laboratory for Advanced Materials Processing of Ministry of Education University of Science and Technology BeijingBeijing 100083China School of Mechanical and Electrical Engineering Xinjiang Institute of EngineeringUrumqi 830023China

As a mathematical analysis method,fractal analysis can be used to quantitatively describe irregular shapes with self-similar or self-affine *** analysis has been used to characterize the shapes of metal materials at various scales and *** methods make it difficult to quantitatively describe the relationship between the regular characteristics and properties of metal material surfaces and ***,fractal analysis can be used to quantitatively describe the shape characteristics of metal materials and to establish the quantitative relationships between the shape characteristics and various properties of metal *** the perspective of two-dimensional planes and three-dimensional curved surfaces,this paper reviews the current research status of the fractal analysis of metal precipitate interfaces,metal grain boundary interfaces,metal-deposited film surfaces,metal fracture surfaces,metal machined surfaces,and metal wear *** relationship between the fractal dimensions and properties of metal material surfaces and interfaces is *** from three perspectives of fractal analysis,namely,research scope,image acquisition methods,and calculation methods,this paper identifies the direction of research on fractal analysis of metal material surfaces and interfaces that need to be *** is believed that revealing the deep influence mechanism between the fractal dimensions and properties of metal material surfaces and interfaces will be the key research direction of the fractal analysis of metal materials in the future.

关键词： metal material surfaces and interfaces fractal analysis fractal dimension homogeneity

A Multi-Objective Particle Swarm Optimization Algorithm Based on Decomposition and Multi-Selection Strategy

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Computers, Materials & Continua 2025年第1期82卷 997-1026页

作者： Li Ma Cai dai Xingsi Xue Cheng Peng School of Computer Science Shaanxi Normal UniversityXi’an710119China Fujian Provincial Key Laboratory of Big Data Mining and Applications Fujian University of TechnologyFuzhou350118China Information Construction and Management Center and Institute of Artificial Intelligence and Educational New Productivity Ningxia Normal UniversityGuyuan756099China

The multi-objective particle swarm optimization algorithm(MOPSO)is widely used to solve multi-objective optimization *** the article,amulti-objective particle swarm optimization algorithmbased on decomposition and multi-selection strategy is proposed to improve the search ***,two update strategies based on decomposition are used to update the evolving population and external archive,***,a multiselection strategy is *** first strategy is for the subspace without a non-dominated *** the neighbor particles,the particle with the smallest penalty-based boundary intersection value is selected as the global optimal solution and the particle far away fromthe search particle and the global optimal solution is selected as the personal optimal solution to enhance global *** second strategy is for the subspace with a non-dominated *** the neighbor particles,two particles are randomly selected,one as the global optimal solution and the other as the personal optimal solution,to enhance local *** third strategy is for Pareto optimal front(PF)discontinuity,which is identified by the cumulative number of iterations of the subspace without non-dominated *** the subsequent iteration,a new probability distribution is used to select from the remaining subspaces to ***,an adaptive inertia weight update strategy based on the dominated degree is designed to further improve the search ***,the proposed algorithmis compared with fivemulti-objective particle swarm optimization algorithms and five multi-objective evolutionary algorithms on 22 test *** results show that the proposed algorithm has better performance.

关键词： Multi-objective optimization multi-objective particle swarm optimization decomposition multi-selection strategy

Oxidation Resistance of Form-stable Hightemperature Phase Change Thermal Energy Storage Materials Doped by Impregnated Graphite

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Journal of Wuhan University of Technology(Materials Science) 2025年第1期40卷 1-12页

作者： LI Baorang dai Jianhuan ZHANG Wei LIU Xiangchen YANG Liu School of Energy Power and Mechanical Engineering North China Electric Power UniversityBeijing 102206China School of Ener-gy and Environment Southeast UniversityNanjing 210096China

We adopted the solution impregnation route with aluminum dihydrogen phosphate solution as liquid medium for effective surface modification on graphite *** mass ratio of graphite to Al(H_(2)PO_(4))_(3) changed from 0.5:1 to 4:1,and the impregnation time changed from 1 to 7 *** typical composite phase change thermal storage materials doped with the as-treated graphite were fabricated using form-stable *** investigate the oxidation and anti-oxidation behavior of the impregnated graphite at high temperatures,the samples were put into a muffle furnace for a cyclic heat *** on SEM,EDS,DSC techniques,analyses on the impregnated technique suggested an optimized processing conditions of a 3 h impregnation time with the ratio of graphite:Al(H_(2)PO_(4))_(3) as 1:3 for graphite impregnation *** investigations on high-temperature phase change heat storage materials doped by the treated graphite suggested excellent oxidation resistance and thermal cycling performance.

关键词： phase change materials graphite impregnation method oxidation,sintering thermal analysis

Peripheral blood RNA biomarkers can predict lesion severity in degenerative cervical myelopathy

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Neural Regeneration Research 2025年第6期20卷 1764-1775页

作者： Zhenzhong Zheng Jialin Chen Jinghong Xu Bin Jiang lei Li Yawei Li Yuliang dai Bing Wang Department of Spine Surgery The Second Xiangya Hospital of Central South UniversityChangshaHunan ProvinceChina

Degenerative cervical myelopathy is a common cause of spinal cord injury,with longer symptom duration and higher myelopathy severity indicating a worse *** numerous studies have investigated serological biomarkers for acute spinal cord injury,few studies have explored such biomarkers for diagnosing degenerative cervical *** study involved 30 patients with degenerative cervical myelopathy(51.3±7.3 years old,12 women and 18 men),seven healthy controls(25.7±1.7 years old,one woman and six men),and nine patients with cervical spondylotic radiculopathy(51.9±8.6 years old,three women and six men).Analysis of blood samples from the three groups showed clear differences in transcriptomic *** analysis identified 128 differentially expressed genes that were enriched in patients with neurological *** least absolute shrinkage and selection operator analysis,we constructed a five-gene model(TBCD,TPM2,PNKD,EIF4G2,and AP5Z1)to diagnose degenerative cervical myelopathy with an accuracy of 93.5%.One-gene models(TCAP and SDHA)identified mild and severe degenerative cervical myelopathy with accuracies of 83.3%and 76.7%,*** of two immune cell types(memory B cells and memory-activated CD4^(+)T cells)predicted levels of lesions in degenerative cervical myelopathy with 80%*** results suggest that peripheral blood RNA biomarkers could be used to predict lesion severity in degenerative cervical myelopathy.

关键词： biomarkers candidate genes degenerative cervical myelopathy gene expression analysis immune cell types neurological disabilities peripheral blood RNA profiles spinal cord injury

Gut microbiota-astrocyte axis: new insights into age-related cognitive decline

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Neural Regeneration Research 2025年第4期20卷 990-1008页

作者： Lan Zhang Jingge Wei Xilei Liu dai Li Xiaoqi Pang Fanglian Chen Hailong Cao Ping lei Haihe Laboratory of Cell Ecosystem Department of GeriatricsTianjin Medical University General HospitalTianjinChina Tianjin Geriatrics Institute Tianjin Medical University General HospitalTianjinChina Department of Gastroenterology and Hepatology Tianjin Medical University General HospitalNational Key Clinical SpecialtyTianjin Institute of Digestive DiseasesTianjin Key Laboratory of Digestive DiseasesTianjinChina Department of Urology Tianjin Medical University General HospitalTianjinChina Tianjin Neurological Institution Tianjin Medical University General HospitalTianjinChina

With the rapidly aging human population,age-related cognitive decline and dementia are becoming increasingly prevalent *** is considered the main risk factor for cognitive decline and acts through alterations in the composition of the gut microbiota,microbial metabolites,and the functions of *** microbiota–gut–brain axis has been the focus of multiple studies and is closely associated with cognitive *** article provides a comprehensive review of the specific changes that occur in the composition of the gut microbiota and microbial metabolites in older individuals and discusses how the aging of astrocytes and reactive astrocytosis are closely related to age-related cognitive decline and neurodegenerative *** article also summarizes the gut microbiota components that affect astrocyte function,mainly through the vagus nerve,immune responses,circadian rhythms,and microbial ***,this article summarizes the mechanism by which the gut microbiota–astrocyte axis plays a role in Alzheimer’s and Parkinson’s *** findings have revealed the critical role of the microbiota–astrocyte axis in age-related cognitive decline,aiding in a deeper understanding of potential gut microbiome-based adjuvant therapy strategies for this condition.

关键词： age aging Alzheimer’s disease astrocytes cognitive decline dementia gut microbiota gut–brain axis microbial metabolites neuroinflammation Parkinson’s disease

SensFL:Privacy-Preserving Vertical Federated learning with Sensitive Regularization

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Computer Modeling in Engineering & Sciences 2025年第1期142卷 385-404页

作者： Chongzhen Zhang Zhichen Liu Xiangrui Xu Fuqiang Hu Jiao dai Baigen Cai Wei Wang School of Automation and Intelligence Beijing Jiaotong UniversityBeijing100044China Shuohuang Railway Development Co. Ltd.National Energy GroupCangzhou062350China Beijing Key Laboratory of Security and Privacy in Intelligent Transportation School of Computer Science and TechnologyBeijing Jiaotong UniversityBeijing100044China

In the realm of Intelligent Railway Transportation Systems,effective multi-party collaboration is crucial due to concerns over privacy and data *** Federated learning(VFL)has emerged as a promising approach to facilitate such collaboration,allowing diverse entities to collectively enhance machine learning models without the need to share sensitive training ***,existing works have highlighted VFL’s susceptibility to privacy inference attacks,where an honest but curious server could potentially reconstruct a client’s raw data from embeddings uploaded by the *** vulnerability poses a significant threat to VFL-based intelligent railway transportation *** this paper,we introduce SensFL,a novel privacy-enhancing method to against privacy inference attacks in ***,SensFL integrates regularization of the sensitivity of embeddings to the original data into the model training process,effectively limiting the information contained in shared *** reducing the sensitivity of embeddings to the original data,SensFL can effectively resist reverse privacy attacks and prevent the reconstruction of the original data from the *** experiments were conducted on four distinct datasets and three different models to demonstrate the efficacy of *** results show that SensFL can effectively mitigate privacy inference attacks while maintaining the accuracy of the primary learning *** results underscore SensFL’s potential to advance privacy protection technologies within VFL-based intelligent railway systems,addressing critical security concerns in collaborative learning environments.

关键词： Vertical federated learning privacy defenses