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Rare Metals 2017年第11期36卷 872-877页

作者： Hui-Bin Xu Song Tang hai-feng xi Peng-Yu Gao Mo-Yang Li School of Materials Science and Engineering Chongqing University of Technology State Key Laboratory of Advance Welding and Joining Harbin Institute of Technology

In this study, 5052 steel were joined by a new way aluminum alloy and Q235 of arc milling brazing, with the Zn15%A1 filler metal and no use of flux. Effect of rotation speed on mechanical properties and microstructure of joint interface was investigated. The results show that increasing rotation speed is in favor of formation of weld and spread of filler metal on substrate. The fine grain with homogeneous composition in brazed seam can be realized by the stronger stirring in pool induced by milling at more higher rotation speed. And, a composite joint reinforced with needle-like or block-like Fe-A1-Zn intermetallic compounds （IMCs） particle can be obtained by arc milling brazing, which comes from the reaction between steel scrape and Zn-A1 filler alloy. The test on strength of joint interface shows that with the increase in rotation speed, there is a peak value in variation ranges of strength of joint interface. This is to say, when rotation speed is 2720 ***-~, the strength of joint has maximum value （182.01 MPa）. Moreover, a thin and discontinuous IMCs layer at joint interface can be obtained by increasing rotation speed. But at a low or high rotation speed, there also is a crack at joint interface, which weakens the strength of joint interface. Only at 2720 ***-1, a good joint interface without an obvious crack can be realized.

关键词： Dissimilar materials Intermetallic compounds Rotation speed Arc brazing Milling

Defect Engineering with Rational Dopants Modulation for High‑Temperature Energy Harvesting in Lead‑Free Piezoceramics

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Nano-Micro Letters 2025年第3期17卷 87-101页

作者： Kaibiao xi Jianzhe Guo Mupeng Zheng Mankang Zhu Yudong Hou Key Laboratory of Advanced Functional Materials Ministry of EducationCollege of Materials Science and EngineeringBeijing University of TechnologyBeijing 100124People’s Republic of China

High temperature piezoelectric energy harvester(HTPEH)is an important solution to replace chemical battery to achieve independent power supply of HT wireless ***,simultaneously excellent performances,including high figure of merit(FOM),insulation resistivity(ρ)and depolarization temperature(Td)are indispensable but hard to achieve in lead-free piezoceramics,especially operating at 250°C has not been reported ***,well-balanced performances are achieved in BiFeO3–BaTiO3 ceramics via innovative defect engineering with respect to delicate manganese *** to the synergistic effect of enhancing electrostrictive coefficient by polarization configuration optimization,regulating iron ion oxidation state by high valence manganese ion and stabilizing domain orientation by defect dipole,comprehensive excellent electrical performances(Td=340°C,ρ250°C>10^(7)Ωcm and FOM_(250°C)=4905×10^(–15)m^(2)N^(−1))are realized at the solid solubility limit of manganese *** HT-PEHs assembled using the rationally designed piezoceramic can allow for fast charging of commercial electrolytic capacitor at 250°C with high energy conversion efficiency(η=11.43%).These characteristics demonstrate that defect engineering tailored BF-BT can satisfy high-end HT-PEHs requirements,paving a new way in developing selfpowered wireless sensors working in HT environments.

关键词： Lead-free piezoceramic Defect engineering Dopants modulation High-temperature Piezoelectric energy harvester

Structural Modal Parameter Recognition and Related Damage Identification Methods under Environmental Excitations: A Review

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Structural Durability & Health Monitoring 2025年第1期19卷 25-54页

作者： Chao Zhang Shang-xi Lai Hua-Ping Wang School of Civil Engineering and Mechanics Lanzhou UniversityLanzhou730000China Key Laboratory of Special Functional Materials and Structural Design Ministry of EducationLanzhou UniversityLanzhou730000China

Modal parameters can accurately characterize the structural dynamic properties and assess the physical state of the ***,it is particularly signiﬁcant to identify the structural modal parameters according to the monitoring data information in the structural health monitoring(SHM)system,so as to provide a scientiﬁc basis for structural damage identiﬁcation and dynamic model modiﬁ*** view of this,this paper reviews methods for identifying structural modal parameters under environmental excitation and brieﬂy describes how to identify structural damages based on the derived modal *** paper primarily introduces data-driven modal parameter recognition methods(e.g.,time-domain,frequency-domain,and time-frequency-domain methods,etc.),brieﬂy describes damage identiﬁcation methods based on the variations of modal parameters(e.g.,natural frequency,modal shapes,and curvature modal shapes,etc.)and modal validation methods(e.g.,Stability Diagram and Modal Assurance Criterion,etc.).The current status of the application of artiﬁcial intelligence(AI)methods in the direction of modal parameter recognition and damage identiﬁcation is further *** on the pre-vious analysis,the main development trends of structural modal parameter recognition and damage identiﬁcation methods are given to provide scientiﬁc references for the optimized design and functional upgrading of SHM systems.

关键词： Structural health monitoring data information modal parameters damage identiﬁcation AI method

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编组站分阶段发展模型研究

铁道运输与经济 2008年第7期30卷 92-94页

作者：张天伟徐海锋王希良石家庄铁道学院交通工程分院河北石家庄050043

根据我国编组站的发展建设情况,提出对编组站的每一个发展阶段作出合理的建设决策,使各发展阶段所需投资额之和最小。为此建立了编组站分阶段发展的非线性动态规划模型,因考虑模型求解有一定难度,但可以转化为最短径路模型求解。通过算... 详细信息

根据我国编组站的发展建设情况,提出对编组站的每一个发展阶段作出合理的建设决策,使各发展阶段所需投资额之和最小。为此建立了编组站分阶段发展的非线性动态规划模型,因考虑模型求解有一定难度,但可以转化为最短径路模型求解。通过算例应用给出了具体求解方法,并对该模型的适用范围进行了说明。

关键词：编组站发展阶段投资额模型

Smart Cellulose‑Based Janus Fabrics with Switchable Liquid Transportation for Personal Moisture and Thermal Management

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Nano-Micro Letters 2025年第1期17卷 333-347页

作者： Jianfeng xi Yanling Lou Liucheng Meng Chao Deng Youlu Chu Zhaoyang Xu Huining xiao Weibing Wu Jiangsu Co‑Innovation Center of Efficient Processing and Utilization of Forest Resources International Innovation Center for Forest Chemicals and MaterialsJiangsu Provincial Key Lab of Sustainable Pulp and Paper Technology and Biomass MaterialsNanjing Forestry UniversityNanjing 210037People’s Republic of China College of Materials Science and Engineering Nanjing Forestry UniversityNanjing 210037People’s Republic of China Department of Chemical Engineering University of New BrunswickFrederictonNB E3B 5A3Canada Macromolecular Chemistry and Bavarian Polymer Institute University of BayreuthBayreuth 95440Germany

The Janus fabrics designed for personal moisture/thermal regulation have garnered significant attention for their potential to enhance human ***,the development of smart and dynamic fabrics capable of managing personal moisture/thermal comfort in response to changing external environments remains a ***,a smart cellulose-based Janus fabric was designed to dynamically manage personal moisture/*** cotton fabric was grafted with N-isopropylacrylamide to construct a temperature-stimulated transport ***,hydrophobic ethyl cellulose and hydrophilic cellulose nanofiber were sprayed on the bottom and top sides of the fabric to obtain wettability *** fabric exhibits anti-gravity directional liquid transportation from hydrophobic side to hydrophilic side,and can dynamically and continuously control the transportation time in a wide range of 3–66 s as the temperature increases from 10 to 40℃.This smart fabric can quickly dissipate heat at high temperatures,while at low temperatures,it can slow down the heat dissipation rate and prevent the human from becoming too *** addition,the fabric has UV shielding and photodynamic antibacterial properties through depositing graphitic carbon nitride nanosheets on the hydrophilic *** smart fabric offers an innovative approach to maximizing personal comfort in environments with significant temperature variations.

关键词： Directional water transport Cotton fabric Anti-gravity directional liquid transportation Janus wettability

低估的自我——中等收入群体收入波动与主观阶层认同研究

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山西财经大学学报 2025年第1期47卷 1-15页

作者：陈涛峰杨希雷南开大学经济学院山东女子学院经济学院

中等收入群体作为社会的中坚力量，当其主观认同自身阶层时，能更有效地促进社会的经济发展与稳定。基于2010—2020年CFPS数据研究发现，我国中等收入群体存在明显的低位阶层认同现象，并且收入波动是导致这一现象产生的重要因素。机制... 详细信息

中等收入群体作为社会的中坚力量，当其主观认同自身阶层时，能更有效地促进社会的经济发展与稳定。基于2010—2020年CFPS数据研究发现，我国中等收入群体存在明显的低位阶层认同现象，并且收入波动是导致这一现象产生的重要因素。机制检验发现，收入波动通过改变中等收入群体对未来的预期、消费结构和对代际传递的担忧，影响其主观阶层认同感。调节效应分析显示，是否连续处于中等收入群体和家庭资产的数量是重要的调节变量。

关键词：中等收入群体收入波动主观阶层认同认同下移偏差低位认同未来预期消费结构代际传递

The prediction on in-line vortex-induced vibration of slender marine structures

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Acta Mechanica Sinica 2012年第5期28卷 1303-1308页

作者： Wan-hai Xu xi-feng Gao Jie Du State Key Laboratory of Hydraulic Engineering Simulation and Safety School of Civil EngineeringTianjin University

The in-line （IL） vortex-induced vibration （VIV） that occurs frequently in ocean engineering may cause severe fatigue damage in slender marine structures. To the best knowledge of the authors, in existing literatures, there is no efficient analytical model for predicting pure IL VIV. In this paper, a wake oscillator model capable of analyzing the IL VIV of slender marine structures has been developed. Two different kinds of van der Pol equations are used to describe the near wake dynamics related to the fluctuating nature of symmetric vortex shedding in the first excitation region and alternate vortex shedding in the second one. Some comparisons are carried out between the present model results and experimental data. It is found that many phenomena observed in experiments could be reproduced by the present wake oscillator model.

关键词： Vortex-induced vibration Wake oscillatormodel In-line Slender marine structures

Vortex-Induced Vibrations of A Free-Spanning Pipe Based on A Nonlinear Hysteretic Soil Model at the Shoulders

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China Ocean Engineering 2020年第3期34卷 328-340页

作者： GAO xi-feng xiE Wu-de XU Wan-hai State Key Laboratory of Hydraulic Engineering Simulation and Safety Tianjin UniversityTianjin 300072China

The pipe-soil interactions at shoulders can significantly affect the vortex-induced vibrations (VIV) of free-spanning pipes in the subsea. In this paper, the seabed soil reacting force on the pipe is directly calculated with a nonlinear hysteretic soil model. For the VIV in the middle span, a classic van der Pol wake oscillator is adopted. Based on the Euler-Bernoulli beam theory, the vibration equations of the pipe are obtained which are different in the middle span and at the two end shoulders. The static configuration of the pipe is firstly calculated and then the VIV is *** present model is validated with the comparisons of VIV experiment, pipe-soil interaction experiment and the simulation results of VIV of free-spanning pipes in which the seabed soil is modelled with spring-dashpots. With the present model, the influence of seabed soil on the VIV of a free-spanning pipe is analyzed. The parametric studies show that when the seabed soil has a larger suction area, the pipe vibrates with smaller bending stresses and is *** with the increase of the shear strength of the seabed soil, the bending stresses increase and the pipe faces more danger.

关键词： free-spanning pipe vortex-induced vibrations nonlinear hysteretic soil model bending stresses

FUBP3 mediates the amyloid-β-induced neuronal NLRP3 expression

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Neural Regeneration Research 2025年第7期20卷 2068-2083页

作者： Jing Yao Yuan Li xi Liu Wenping Liang Yu Li Liyong Wu Zhe Wang Weihong Song The National Clinical Research Center for Geriatric Disease Xuanwu HospitalCapital Medical UniversityBeijingChina Department of Neurology The First Affiliated Hospital of Zhengzhou UniversityZhengzhouHenan ProvinceChina Department of Neurosurgery Xuanwu HospitalCapital Medical UniversityBeijingChina Department of Pediatrics The Second Affiliated Hospital and Yuying Children’s HospitalKey Laboratory of Alzheimer’s Disease of Zhejiang ProvinceInstitute of AgingWenzhou Medical UniversityWenzhouZhejiang ProvinceChina Oujiang Laboratory(Zhejiang Laboratory for Regenerative Medicine Visionand Brain Health)WenzhouZhejiang ProvinceChina

Alzheimer's disease is characterized by deposition of amyloid-β,which forms extracellular neuritic plaques,and accumulation of hyperphosphorylated tau,which aggregates to form intraneuronal neurofibrillary tangles,in the *** NLRP3 inflammasome may play a role in the transition from amyloid-βdeposition to tau phosphorylation and *** NLRP3 is primarily found in brain microglia,and tau is predominantly located in neurons,it has been suggested that NLRP3 expressed by microglia indirectly triggers tau phosphorylation by upregulating the expression of pro-inflammatory ***,we found that neurons also express NLRP3 in vitro and in vivo,and that neuronal NLRP3 regulates tau *** biochemical methods,we mapped the minimal NLRP3 promoter and identified FUBP3 as a transcription factor regulating NLRP3 expression in *** primary neurons and the neuroblastoma cell line Neuro2A,FUBP3 is required for endogenous NLRP3 expression and tau phosphorylation only when amyloid-βis *** the brains of aged wild-type mice and a mouse model of Alzheimer's disease,FUBP3 expression was markedly increased in cortical *** analysis suggested that FUBP3 plays a role in neuron-mediated immune *** also found that FUBP3 trimmed the 5′end of DNA fragments that it bound,implying that FUBP3 functions in stress-induced *** findings suggest that neuronal NLRP3 may be more directly involved in the amyloid-β-to–phospho-tau transition than microglial NLRP3,and that amyloid-βfundamentally alters the regulatory mechanism of NLRP3 expression in *** that FUBP3 was only expressed at low levels in young wild-type mice and was strongly upregulated in the brains of aged mice and Alzheimer's disease mice,FUBP3 could be a safe therapeutic target for preventing Alzheimer's disease progression.

关键词： 5′end trimming Alzheimer's disease amyloid-beta amyloid-β-dependent transcription FUBP3 inflammasome inflammation neuron NLRP3 tau transcription factor

Use of Helical Strakes for FIV Suppression of Two Inclined Flexible Cylinders in A Side-by-Side Arrangement

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China Ocean Engineering 2018年第3期32卷 331-340页

作者： XU Wan-hai ZHANG Shu-hai ZHOU Li-dan GAO xi-feng State Key Laboratory of Hydraulic Engineering Simulation and Safety Tianjin UniversityTianjin 300072China Collaborative Innovation Centre for Advanced Ship and Deep-Sea Exploration Shanghai 200240China

The experimental studies on flow-induced vibrations(FIV) reduction of two side-by-side flexible cylinders inclined at 45° by using the helical strakes were carried out in a towing tank. The main aim of the experiment is to check whether the helical strakes with a pitch of 17.5 D and a height of 0.25 D, which is considered as the most effective vibration suppression device for the isolated cylinder undergoing vortex-shedding, still perform very well to reduce FIV of two inclined flexible cylinders in a side-by-side arrangement. The vibration of two identical inclined cylinders with a mass ratio of 1.90 and an aspect ratio of 350 was tested in the experiment. The center-to-center distance between the two cylinders was 3.0 D. The uniform flow was simulated by towing the cylinder models along the *** towing velocity varied from 0.05 to 1.0 m/s with an interval of 0.05 m/s. The maximum Reynolds number can be up to 1.6×104. Three cases were experimentally studied in this paper, including two side-by-side inclined smooth cylinders, only one smooth cylinder fitted with helical strakes in the two side-by-side inclined cylinders system and both two cylinders attached with helical strakes. The variations of displacement amplitude, dominant frequency, FIV suppression efficiency and dominant mode for the two side-by-side inclined cylinders with reduced velocity were shown and discussed.

关键词： helical strakes FIV suppression inclined cylinder side-by-side towing tank experiment