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baTiO_(3)solid solutions co-doped with Gd^(3+)and Eu^(3+):Synthesis,structural evolution and dielectric properties

Journal of rare Earths 2024年第10期42卷 1920-1926页

作者： R.Martínez-lópez M.pérez-labra J.A.Romero-Serrano F.R.barrientos-Hernández M.Reyes-pérez M.I.Valenzuela-carrillo G.Urbano-Reyes V.E.Reyes-Cruz G.I.Dávila-pulido Academic Area of Earth Sciences and Materials Autonomous University of Hidalgo StateRoad Pachuca-Tulancingo Km 4.5 Mineral de La Reforma.Hidalgo42184Mexico Metallurgy and Materials Department ESIQIE-IPNUPALMZacatencoCiudad de Mexico07738Mexico Autonomous University of Coahuila Boulevard Adolfo López Mateos S/nNueva RositaCoahuila26800Mexico

In this paper,the synthesis,structural evolution,and dielectric properties of baTiO_(3)solid solutions codoped with rare earth elements(Gd^(3+)and Eu^(3+))prepared using the solid-state reaction method are *** pure precursor powders of baCl_3,TiO_(2),Gd_(2)O_(3),and Eu_(2)O_(3)were mixed in stoichiometric proportions,ground in an agate mortar before being uniaxially pressed at 250 Mpa and sintered at 1300℃in air atmosphere for 6 h to obtain ba_(1-3x)Gd_(2x)Ti_(1-3x)Eu_(4x)O_(3)(x=0,0.0015,0.01 and0.1).X-ray diffraction(XRD)and Rietveld's refinement results reveal the crystal phase ferroelectric tetragonal baTiO_(3)for the samples with x=0,0.0015 and 0.01,as well as a consistent increment in the lattice parameters caused by the *** solubility limit of Gd^(3+)and Eu^(3+)in the baTiO_(3)structure is reached for the sample with x>0.01,and the orthorhombic Eu_2TiO_(5)and monoclinic baTi_(2)O_(5)secondary phases were *** raman results show the characteristic peaks of ferroelectric tetragonal baTiO_(3)around 716 cm^(-1)(lO of A1 symmetry),515 cm^(-1)(TO of A1 symmetry),and 305 cm^(-1)(B1).The maximum relative permittivity measured at 1 kHz was recorded to be 6151.8 for the sample with x=0.0015,and a decrease in the Curie temperature to 105℃with respect to the undoped sample was *** punctual microanalysis for the samples with x=0.0015,0.01,and 0.1 reveals grains composed of ba,Ti,O,Gd,and Eu homogeneously distributed in the baTiO_(3)*** ba/Ti ratios for samples with x=0.0015,0.01 and 0.1 are 2.86,2.91,and 0.68,respectively,indicating substitution at the Ti site for samples with x=0.0015 and 0.01 and a substitution at the ba site for the sample with x=0.1.

关键词： baTiO_(3) Doping Gadolinium Europium Synthesis rare earths

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Comprehensive Evaluation Method for Traffic Flow Data Quality based on Grey Correlation Analysis and particle Swarm Optimization

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Journal of Systems Science and Systems Engineering 2024年第1期33卷 106-128页

作者： Wei ba baojun Chen Qi li School of Automation and electrical Engineering Dalian Jiaotong UniversityDalian116028China Faculty of electronic Information and electrical Engineering Dalian University of TechnologyDalian116023China

Nowadays,data are more and more used for intelligent modeling and prediction,and the comprehensive evaluation of data quality is getting more and more attention as a necessary means to measure whether the data are usable or ***,the comprehensive evaluation method of data quality mostly contains the subjective factors of the evaluator,so how to comprehensively and objectively evaluate the data has become a bottleneck that needs to be solved in the research of comprehensive evaluation *** order to evaluate the data more comprehensively,objectively and differentially,a novel comprehensive evaluation method based on particle swarm optimization(pSO)and grey correlation analysis(Gca)is presented in this *** first,an improved Gca evaluation model based on the technique for order preference by similarity to an ideal solution(TOpSIS)is ***,an objective function model of maximum difference of the comprehensive evaluation values is built,and the pSO algorithm is used to optimize the weights of the improved Gca evaluation model based on the objective function ***,the performance of the proposed method is investigated through parameter analysis.A performance comparison of traffic flow data is carried out,and the simulation results show that the maximum average difference between the evaluation results and its mean value(MDR)of the proposed comprehensive evaluation method is 33.24%higher than that of TOpSIS-Gca,and 6.86%higher than that of *** proposed method has better differentiation than other methods,which means that it objectively and comprehensively evaluates the data from both the relevance and differentiation of the data,and the results more effectively reflect the differences in data quality,which will provide more effective data support for intelligent modeling,prediction and other applications.

关键词： Data quality comprehensive evaluation particle swarm optimization grey correlation analysis traffic flow data

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A simulation-based software to support the real-time operational parameters selection of tunnel boring machines

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Underground Space 2024年第1期14卷 176-196页

作者： Yaman Zendaki ba Trung cao Abdullah Alsahly Steffen Freitag Gunther Meschke Institute for Structural Mechanics Ruhr University BochumBochum 44801Germany Institute for Structural Analysis Karlsruhe Institute of TechnologyKarlsruhe 76131Germany

With the fact that the main operational parameters of the construction process in mechanized tunneling are currently selected based on monitoring data and engineering experience without exploiting the advantages of computer methods,the focus of this work is to develop a simulation-based real-time assistant system to support the selection of operational *** choice of an appropriate set of these parameters(i.e.,the face support pressure,the grouting pressure,and the advance speed)during the operation of tunnel boring machines(TBM)is determined by evaluating different tunneling-induced soil-structure interactions such as the surface settlement,the associated risks on existing structures and the tunnel lining *** evaluate soil-structure behavior,an advanced process-oriented numerical simulation model based on the finite cell method is *** enable the real-time prediction capability of the simulation model for a practical application during the advancement of TBMs,surrogate models based on the proper Orthogonal Decomposition and radial basis Functions(pOD-RBF)are *** proposed approach is demonstrated through several synthetic numerical examples inspired by the data of real tunnel *** developed methods are integrated into a user-friendly application called SMART to serve as a support platform for tunnel engineers at construction *** to each user adjustment of the input parameters,i.e.,each TBM driving scenario,approximately two million outputs of soil-structure interactions are quickly predicted and visualized in seconds,which can provide the site engineers with a rough estimation of the impacts of the chosen scenario on structural responses of the tunnel and above ground structures.

关键词： Numerical simulation Surrogate model Real-time prediction proper orthogonal decomposition radial basis functions TBM operation Smart construction

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Recent progress in the research on magnesium and magnesium alloy foils:A short review

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International Journal of Minerals,Metallurgy and Materials 2024年第5期31卷 842-854页

作者： Qiuyan Shen Yongxing ba peng Zhang Jiangfeng Song Bin Jiang Fusheng pan National Engineering Research Center for Magnesium Alloys Chongqing UniversityChongqing 400044China College of Materials Science and Engineering Chongqing UniversityChongqing 400044China National Key laboratory of Advanced casting Technologies Chongqing UniversityChongqing 400044China

Magnesium and magnesium alloy foils have great potential for application in battery anodes,electromagnetic shielding,optics and acoustics,and biology because of their excellent specific damping,internal dissipation coefficients,magnetic and electrical conductivities,as well as high theoretical specific ***,magnesium alloys exhibit poor deformation ability due to their hexagonal close-packed crystal *** magnesium and magnesium alloy foils with thicknesses of less than 0.1 mm is difficult because of surface oxidation and grain growth at high temperatures or severe anisotropy after cold rolling that leads to *** methods have been applied to prepare magnesium alloy *** include warm rolling,cold rolling,accumulative roll bonding,electric plastic rolling,and on-line heating *** of magnesium and magnesium alloy foils during preparation,such as edge cracks and breakage,are important factors for ***,the current status of the research on magnesium and magnesium alloy foils is summarized from the aspects of foil preparation,defect control,performance characterization,and application *** advantages and disadvantages of different preparation methods and defect(edge cracks and breakage)mechanisms in the preparation of foils are identified.

关键词： magnesium alloy foil rolling defect performance application

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physics-based seismic analysis of ancient wood structure:fault-to-structure simulation

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Earthquake Engineering and Engineering Vibration 2024年第3期23卷 727-740页

作者： ba Zhenning Fu Jisai Wang Fangbo liang Jianwen Zhang Bin Zhang long State Key laboratory of Hydraulic Engineering Intelligent Construction and Operation (Tianjin University)Tianjin 300350China School of Civil Engineering Tianjin UniversityTianjin 300350China Administrative Office of the Summer palace Beijing 100091China School of Architecture Tianjin UniversityTianjin 300072China

based on the domain reduction method,this study employs an SEM-FEM hybrid workflow which integrates the advantages of the spectral element method(SEM)for flexible and highly efficient simulation of seismic wave propagation in a three-dimensional(3D)regional-scale geophysics model and the finite element method(FEM)for fine simulation of structural response including soil-structure interaction,and performs a physics-based simulation from initial fault rupture on an ancient wood *** verification of the hybrid workflow,a large-scale model of an ancient wood structure in the Beijing area,The Tower of Buddhist Incense,is established and its responses under the 1665 Tongxian earthquake and the 1730 Yiheyuan earthquake are *** results from the simulated ground motion and seismic response of the wood structure under the two earthquakes demonstrate that this hybrid workflow can be employed to efficiently provide insight into the relationships between geophysical parameters and the structural response,and is of great significance toward accurate input for seismic simulation of structures under specific site and fault conditions.

关键词： spectral element method finite element method fault-to-structure simulation physical model domain reduction method

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Multi-aspect analysis of ureteral access sheath usage in retrograde intrarenal surgery: A RIRSearch group study

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Asian Journal of Urology 2024年第1期11卷 80-85页

作者： Oktay Özman Hacı M.Akgül Cem başataç Önder Çınar Eyüp B.Sancak Cenk M.Yazıcı Bülent Önal Haluk Akpınar Gaziosmanpasa Training and Research Hospital Urology ClinicİstanbulTurkey TekirdağNamık Kemal University School of MedicineDepartment of UrologyTekirdağTurkey Group Florence Nightingale Hospitals Department of UrologyİstanbulTurkey Zonguldak Bulent Ecevit University School of MedicineDepartment of UrologyZonguldakTurkey Çanakkale Onsekiz Mart University School of MedicineDepartment of UrologyÇanakkaleTurkey İstanbul University-Cerrahpaşa Cerrahpaşa Medical FacultyDepartment of UrologyİstanbulTurkey

Objective:To evaluate the effect of ureteral access sheath(UAS)use and calibration change on stone-free rate and complications of retrograde intrarenal surgery(RIRS).Methods:Data from 568 patients undergoing RIRS for kidney or upper ureteral stones were retrospectively ***,patients were compared after 1:1 propensity score matching,according to UAS usage during RIRS(UAS used[+]87 and UAS non-used[−]87 patients).Then all UAS+patients(n=481)were subdivided according to UAS calibration:9.5-11.5 Fr,10-12 Fr,11-13 Fr,and 13-15 *** outcomes of the study were the success and complications of ***:Stone-free rate of UAS+patients(86.2%)was significantly higher than UAS−patients(70.1%)after propensity score matching(p=0.01).Stone-free rate increased with higher caliber UAS(9.5-11.5 Fr:66.7%;10-12 Fr:87.0%;11-13 Fr:90.6%;13-15 Fr:100%;ppostoperative complications of UAS+patients(11.5%)were significantly lower than UAS−patients(27.6%)(p=0.01).Complications(8.7%)with 9.5-11.5 Fr UAS was lower than thicker UAS(17.2%)but was not statistically significant(p=0.09).UAS usage was an independent factor predicting stone-free status or peri-and post-operative complications(odds ratio[OR]3.654,95%confidence interval[CI]1.314-10.162;OR 4.443,95%CI 1.350-14.552;OR 4.107,95%CI 1.366-12.344,respectively).Conclusion:Use of UAS in RIRS may increase stone-free rates,which also increase with higher caliber *** usage may reduce complications;however,complications seemingly increase with higher UAS calibration.

关键词： Stone Retrograde intrarenal surgery Ureteral access sheath Urolithiasis Kidney

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The value of toxicological analysis in acute poisoning patients with uncertain exposure histories:a retrospective and descriptive study from an institute of poisoning

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World Journal of Emergency Medicine 2024年第2期15卷 98-104页

作者： Qifang Shi Gen ba Zhenyu Xia Zhengsheng Mao Hao Sun Jinsong Zhang Institute of poisoning Nanjing Medical UniversityNanjing 211100China Department of Emergency Medicine the First Affiliated Hospital of Nanjing Medical UniversityNanjing 210029China Department of Forensic Medicine Nanjing Medical UniversityNanjing 211166China The Key laboratory of Modern Toxicology of Ministry of Education Nanjing Medical UniversityNanjing 211166China

baCKGROUND:In clinical practice,some patients might not be able or unwilling to provide a thorough history of medication and poison *** aim of this study was to use toxicological analysis to examine the clinical characteristics of patients with acute poisoning whose exposure history was uncertain from a toxicological analysis ***:This was a retrospective and descriptive study from an institute of *** registration information and test reports spanning the period from April 1,2020 to March 31,2022,were *** with uncertain exposure histories and who underwent toxicological analysis were *** manifestations and categories of toxics were ***:Among the 195 patients with positive toxicological analysis results,the main causes of uncertain exposure history was disturbance of consciousness(62.6%),unawareness(23.6%)and unwillingness or lack of cooperation(13.8%).The predominant clinical manifestations were disturbed consciousness(62.6%),followed by vomiting and nausea(14.4%)and liver function abnormalities(8.7%).A comparison of clinical manifestations between patients with positive and negative(n=99)toxicological analyses results revealed significantly different proportions of disturbances in consciousness(63%vs.21%),dizziness(1.5%vs.5.1%),multi-organ failure(1.5%vs.7.1%),and local pain(0 vs 4%).The main categories of substances involved were psychiatric medications(23.1%),sedatives(20.5%),insecticides(13.8%),and herbicides(12.8%).CONClUSION:The clinical manifestations of acute poisoning in patients with an uncertain exposure history are diverse and nonspecific,and toxicological analysis plays a pivotal role in the diagnosis and differential diagnosis of such patients.

关键词： Acute poisoning Toxic exposure Toxicological analysis Clinical manifestation

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Force Compensation Control for electro-Hydraulic Servo System with pump-Valve Compound Drive via QFT-DTOC

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Chinese Journal of Mechanical Engineering 2024年第2期37卷 228-246页

作者： Kaixian ba Yuan Wang Xiaolong He Chunyu Wang Bin Yu Yaliang liu Xiangdong Kong Hebei provincial Key laboratory of Heavy Machinery Fluid power Transmission and Control Qinhuangdao 066004China School of Mechanical Engineering Yanshan UniversityQinhuangdao 066004China National Engineering Research Center for local Joint of Advanced Manufacturing Technology and Equipment Yanshan UniversityQinhuangdao 066004China

Each joint of a hydraulic-driven legged robot adopts a highly integrated hydraulic drive unit(HDU),which features a high power-weight ***,most HDUs are throttling-valve-controlled cylinder systems,which exhibit high energy *** contrast,pump control systems offer a high ***,their response ability is *** fully utilize the advantages of pump and valve control systems,in this study,a new type of pump-valve compound drive system(pCDS)is designed,which can not only effectively reduce the energy loss,but can also ensure the response speed and response accuracy of the HDUs in robot joints to satisfy the performance requirements of ***,considering the force control requirements of energy conservation,high precision,and fast response of the robot joint HDU,a nonlinear mathematical model of the pCDS force control system is first *** addition,pressure-flow nonlinearity,friction nonlinearity,load complexity and variability,and other factors affecting the system are considered,and a novel force control method based on quantitative feedback theory(QFT)and a disturbance torque observer(DTO)is designed,which is denoted as QFT-DTOC *** method improves the control accuracy and robustness of the force control system,reduces the effect of the disturbance torque on the control performance of the servo motor,and improves the overall force control performance of the ***,experimental verification is performed using the pCDS performance test *** experimental results and quantitative data show that the QFT-DTOC proposed herein can significantly improve the force control performance of the *** relevant force control method can be used as a bottom-control method for the hydraulic servo system to provide a foundation for implementing the top-level trajectory planning of the robot.

关键词： legged robot pump-valve compound drive system(pCDS) Force compensation control Quantitative feedback theory(QFT) Disturbance torque observer(DTO)

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Aggregation of CeAlO_(3) inclusions in heavy ingot of a steel containing 0.007% aluminum

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Journal of Iron and Steel Research International 2024年第8期31卷 1960-1972页

作者： Qiu-yue Zhou Jun-tao ba lun Zhang Wei Chen Ying Ren li-feng Zhang School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China School of Mechanical Engineering Yanshan UniversityQinhuangdao 066004HebeiChina School of Mechanical and Materials Engineering North China University of TechnologyBeijing 100144China

The distribution of inclusions at the bottom of a Ce-treated heavy steel ingot was detected and *** three-dimensional morphology and spatial distribution of CeAlOs clusters were characterized using the electrolytic extraction and Micro-CT detection.A model of inclusion collision to predict the aggregation of CeAlO_(3) inclusions in the ingot was established and validated by measured *** were mainly CeAlO_(3) and a small amount of Ce_(2)O_(2)S in the tundish after cerium *** collision and aggregation of inclusions led to the formation of large clusters in the ingot during the solidification *** slag entrainment inclusions,large CeAO_(3) clusters and small CeAlO_(3) particles were observed from the center to the edge of the ingot *** inclusions were mainly concentrated at the *** number density of inclusions larger than 200μm was 0.21 mm^(-3).The maximum diameter of CeA1O_(3) clusters was 1340μ*** the edge to the radial center and from the bottom to the top,the average diameter of inclusions gradually increased due to the longer solidification time of the ingot.

关键词： Inclusion Heavy ingot Cerium treatment Collision

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Efficacy and safety of electroacupuncture for insomnia:A systematic review and meta-analysis

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Journal of Integrative Medicine 2024年第4期22卷 459-472页

作者： Han-yu Xu lin-na Wu Yuan Zhang Te ba Xiao-feng Zhao Acupuncture and Moxibustion Department First Teaching Hospital of Tianjin University of Traditional Chinese MedicineTianjin 300193China National Clinical Research Center for Chinese Medicine Acupuncture and Moxibustion Tianjin 300193China

background:electroacupuncture is often used to treat ***:To evaluate the efficacy and safety of electroacupuncture for *** strategy:Databases including pubMed,Cochrane library,Embase,Web of Science,Chinese Biomedical literature Database,China National Knowledge Infrastructure,Wanfang Data and VIp Fulltext e-Journals Database were searched up to january 15,*** criteria:randomized clinical trials were included if they compared the clinical efficacy and safety of electroacupuncture with sham acupuncture,no treatment or usual care (UC) and general *** extraction and analysis:The full texts of the studies were reviewed to remove ineligible *** extracted data included authors,publication year,diagnostic criteria,sample size,population characteristics,interventions and *** above steps were performed independently by two reviewers and the data were cross ***15.0 software was used to analyze the extracted outcome *** continuous data (pittsburgh Sleep Quality Index[pSQI]score and Insomnia Severity Index score),weighted mean difference (WMD) was calculated and 95% confidence interval (CI) was reported when the same scale was *** dichotomous variables (clinical response rate and adverse events),a meta-analysis was performed using risk ratio (RR) as the effect ***:Thirty-one trials with 2226 subjects were *** meta-analysis suggested that electroacupuncture was more effective in improving insomnia compared with the control group (sham acupuncture,no treatment,UC and general acupuncture)(RR=1.21;95 CI:[1.16,1.27]),significantly reducing the pSQI score in insomnia patients after treatment and at follow-up (WMD=-3.23;95%CI:[-4.29,-2.17];pcant difference in the incidence of adverse events between the EA and control groups (sham acupuncture and no treatment or ***=1.48;95%CI:[0.91,2.40];p=0.117).In addition,the regression results revealed t

关键词： electroacupuncture Insomnia Systematic review Meta-analysis

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