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Earthquake Engineering and Engineering Vibration 2024年第2期23卷 511-524页

作者： lei zhenbo Liu Gang Wang Hui Hui Yi School of Civil Engineering Chongqing UniversityChongqing 400045China Key Laboratory of New Technology for Construction of Cities in Mountain Area Chongqing UniversityMinistry of EducationChongqing 400045China

With the rapid development of large megawatt wind turbines,the operation environment of wind turbine towers(WTTs)has become increasingly *** particular,seismic excitation can create a resonance response and cause excessive vibration of the *** investigate the vibration attenuation performance of the WTT under seismic excitations,a novel passive vibration control device,called a prestressed tuned mass damper(PS-TMD),is presented in this ***,a mathematical model is established based on structural dynamics under seismic ***,the mathematical analytical expression of the dynamic coefficient is deduced,and the parameter design method is obtained by system tuning ***,based on a theoretical analysis and parameter design,the numerical results showed that the PS-TMD was able to effectively mitigate the resonance under the harmonic basal ***,the time-history analysis method is used to verify the effectiveness of the traditional pendulum tuned mass damper(PTMD)and the novel PS-TMD device,and the results indicate that the vibration attenuation performance of the PS-TMD is better than the *** addition,the PS-TMD avoids the nonlinear effect due to the large oscillation angle,and has the potential to dissipate hysteretic energy under seismic excitation.

关键词： wind turbine tower prestressed tuned mass damper vibration control seismic excitation numerical simulation

钢制风力机塔架非线性预应力调谐质量阻尼器振动控制性能研究

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振动与冲击 2023年第22期42卷 84-92,240页

作者：雷振博刘纲王晖重庆大学土木工程学院重庆400044 重庆大学山地城镇建设与新技术教育部重点实验室重庆400045

悬吊式调谐质量阻尼器原理明确、安装简便,已在高层建筑、高耸输电塔等众多结构中得到了广泛应用,近年来在钢制风力机塔筒方面也逐步得到广泛关注。预应力调谐质量阻尼器(prestressed tuned mass damper,PS-TMD)通过附加下拉索并施加预... 详细信息

悬吊式调谐质量阻尼器原理明确、安装简便,已在高层建筑、高耸输电塔等众多结构中得到了广泛应用,近年来在钢制风力机塔筒方面也逐步得到广泛关注。预应力调谐质量阻尼器(prestressed tuned mass damper,PS-TMD)通过附加下拉索并施加预拉力,可采用摆长和预拉力两个参数进行振动控制调谐,在高柔钢制风力机塔架振动控制中能充分发挥作用。但PS-TMD中拉索变形会引起非线性响应,进而影响控制性能。鉴于此,基于动力学原理建立考虑柔索效应的PS-TMD非线性运动方程,推导了拉索发生变形情况下PS-TMD动力系数及分支共振点频率比;通过优化分析给出了PS-TMD最佳调谐参数的选择方法;某3.2 MW风力机塔筒数值算例结果表明,考虑柔索效应后PS-TMD的动力系数幅值小于同参数下线性PS-TMD,共振响应下减振性能和能量耗散能力更为突出。5组风载荷下振动控制结果表明,考虑柔索效应后PS-TMD对塔架结构的风致响应振动控制效果优于相应线性PS-TMD系统。

关键词：钢制风力机塔架预应力调谐质量阻尼器(PS-TMD) 振动控制拉索柔性变形非线性

地震作用下风力机塔架预应力调谐质量阻尼器振动控制性能研究

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土木工程学报 2022年第S01期55卷 92-100页

作者：雷振博刘纲王晖刘淇重庆大学土木工程学院重庆400045 重庆大学山地城镇建设与新技术教育部重点实验室重庆400044

随着大兆瓦风力机的快速发展及推广普及,风电机组服役运行环境日益复杂。特别突出的是地震激励容易诱发风力机塔架的过度振动,其不仅会损耗发电效率,而且将缩短塔架的疲劳寿命。为了有效缓解地震激励下风力机塔架结构的不利振动,文章针... 详细信息

随着大兆瓦风力机的快速发展及推广普及,风电机组服役运行环境日益复杂。特别突出的是地震激励容易诱发风力机塔架的过度振动,其不仅会损耗发电效率,而且将缩短塔架的疲劳寿命。为了有效缓解地震激励下风力机塔架结构的不利振动,文章针对新型被动控制装置预应力调谐质量阻尼器(PS-TMD)来研究其在地震作用下的减振控制性能。首先,基于结构动力学理论建立了动力学模型,推导了体系动力系数的数学解析表达式。然后,通过系统优化理论获取了地震激励下的装置的参数设计方法。基于理论分析和参数设计,通过3.4MW风力机的数值算例结果表明,PS-TMD能有效地缓解谐振基底加速度下塔架的共振响应。最后,利用ANSYS动力时程分析法验证了PS-TMD振动控制装置的有效性及合理性,结果表明该装置可以显著降低风力机塔架因基频共振致使的动力响应。此外,PS-TMD不会产生因摆角致使的非线性效应,且其在地震激励下具有预期的滞回耗能及变形能力。

关键词：风力机塔架地震激励 PS-TMD 振动控制数值仿真

基于Rayleigh法的风机塔筒预应力基本频率解析计算方法

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振动与冲击 2022年第10期41卷 23-29,65页

作者：雷振博刘纲杨微李杨重庆大学土木工程学院重庆400045 重庆大学山地城镇建设与新技术教育部重点实验室重庆400045 中国船舶重工集团海装风电股份有限公司重庆401122 重庆大学机械工程学院重庆400044

风机大型化发展趋势使塔筒高度更高、柔性更大,塔筒直径及壁厚随高度变化更加多样,使传统简化基频解析计算方法计算精度大幅下降,较难满足塔筒设计前期基频估算要求。引入等效壁厚、平均等效当量惯性矩考虑塔筒直径和壁厚沿高度的多种... 详细信息

风机大型化发展趋势使塔筒高度更高、柔性更大,塔筒直径及壁厚随高度变化更加多样,使传统简化基频解析计算方法计算精度大幅下降,较难满足塔筒设计前期基频估算要求。引入等效壁厚、平均等效当量惯性矩考虑塔筒直径和壁厚沿高度的多种变化情况,简化塔筒刚度计算;基于Rayleigh能量法基本原理,考虑风轮和机舱质量对塔筒预压应力、质量偏心以及塔筒不同变形形式对基频计算的影响,提出了相应的塔筒基频解析计算方法。塔筒数值算例和实验室缩尺试验表明:顶部机舱、叶轮质量偏心对塔筒基频影响较大,解析计算时应考虑其影响;均布荷载变形下的塔筒基频解析值更接近真实值;所提解析法与精细化有限元模型计算值的偏差小于4%,与缩尺模型实测值的偏差小于5%。

关键词：风机塔筒基本频率 Rayleigh法变形形状质量偏心

Allelic reprogramming of chromatin states in human early embryos

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National Science Review 2024年第03期11卷 58-71页

作者： Shenli Yuan lei Gao Wenrong Tao Jianhong Zhan Gang Lu Jingye Zhang Chuanxin Zhang Lizhi Yi zhenbo Liu Zhenzhen Hou Min Dai Han Zhao Zi-Jiang Chen Jiang Liu Keliang Wu Center for Reproductive Medicine Shandong University CAS Key Laboratory of Genome Sciences and Information Collaborative Innovation Center of Genetics and Development Beijing Institute of Genomicsand China National Center for BioinformationChinese Academy of Sciences University of Chinese Academy of Sciences CUHK-SDU Joint Laboratory on Reproductive Genetics School of Biomedical Sciences the Chinese University of Hong Kong Key Laboratory of Reproductive Endocrinology of the Ministry of Education Shandong University Center for Reproductive Medicine Ren Ji Hospital School of Medicine Shanghai Jiao Tong University CAS Center for Excellence in Animal Evolution and Genetics Chinese Academy of Sciences

The reprogramming of parental epigenomes in human early embryos remains elusive. To what extent the characteristics of parental epigenomes are conserved between humans and mice is currently unknown. Here,we mapped parental haploid epigenomes using human parthenogenetic and androgenetic embryos. Human embryos have a larger portion of genome with parentally specific epigenetic states than mouse *** allelic patterns of epigenetic states for orthologous regions are not conserved between humans and mice. Nevertheless, it is conserved that maternal DNA methylation and paternal H3K27me3 are associated with the repression of two alleles in humans and mice. In addition, for DNA-methylation-dependent imprinting, we report 19 novel imprinted genes and their associated germline differentially methylated regions. Unlike in mice, H3K27me3-dependent imprinting is not observed in human early ***, allele-specific epigenomic reprogramming is different in humans and mice.

关键词： human embryo epigenetics reprogramming DNA methylation H3K27me3 chromatin accessibility

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风力机塔架结构振动控制研究及方法综述

船舶工程 2020年第S2期42卷 248-253页

作者：李杨兰涌森李强雷振博刘纲中国船舶重工集团海装风电股份有限公司重庆400037 重庆大学土木工程学院重庆400045

随着风电机组向大兆瓦方向发展,风力机塔架的高柔特性愈发显著,在风、波浪及地震等运动荷载下塔架的振动日益明显,易造成机舱内齿轮、传动轴和发电机等零部件啮合失效,以及塔架底部的连接螺栓松动、剪断,严重时可能导致整个风力机组发... 详细信息

随着风电机组向大兆瓦方向发展,风力机塔架的高柔特性愈发显著,在风、波浪及地震等运动荷载下塔架的振动日益明显,易造成机舱内齿轮、传动轴和发电机等零部件啮合失效,以及塔架底部的连接螺栓松动、剪断,严重时可能导致整个风力机组发生损毁等恶性灾害事故。因此,风力发电机塔架结构的振动控制问题已成为前风电产业亟待解决的关键问题之一。文章在简述风力发电机塔架结构形式及振动特性的基础上,回顾国内外塔架减振控制的研究现状,梳理相关振动控制方法及减振装置所取得的研究成果,展望塔架振动控制未来研究趋势。

关键词：风力发电机塔架结构振动控制减振装置研究综述

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高压降控制阀内空化流动特性实验与数值研究

华中科技大学学报（自然科学版） 2024年第1期52卷 39-45页

作者：徐晓刚王朝磊雷毛王振波兰州理工大学石油化工学院甘肃兰州730050 中国石油大学(华东)新能源学院山东青岛266580

针对高压降工况控制阀存在的严重空化、高能耗及振动噪声等问题,采用实验研究与LES数值研究相结合的方法对控制阀内空化流动特性开展研究,捕捉空腔初生、发展及脱落等流动细节特征,研究不同空腔演化阶段的流动能量传递与损失特性,分析... 详细信息

针对高压降工况控制阀存在的严重空化、高能耗及振动噪声等问题,采用实验研究与LES数值研究相结合的方法对控制阀内空化流动特性开展研究,捕捉空腔初生、发展及脱落等流动细节特征,研究不同空腔演化阶段的流动能量传递与损失特性,分析不同工况条件对阀门流通能力的影响规律.结果表明:控制阀节流空化过程中,阀座喉管与渐扩段区域空化程度较高;空化流动条件下,总机械能损失由节流局部能量损失与空化附加能量损失叠加而成;随压差增大,总流阻中空化附加流阻占比由5.3%逐渐增加至26.7%,空化程度越严重,空化附加流阻越高,造成控制阀总流阻上升与流通能力下降.

关键词：控制阀空化非定常流动流通能力振动噪声

Fabrication of C@MoxTi1-xO2-δ nanocrystalline with functionalized interface as efficient and robust PtRu catalyst support for methanol electrooxidation

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Journal of Energy Chemistry 2020年第1期29卷 7-14,I0001页

作者： Jialong Li lei Zhao Xifei Li Sue Hao zhenbo Wang MIT Key Laboratory of Critical Materials Technology for New Energy Conversion and Storage School of Chemistry and Chemical EngineeringHarbin Institute of TechnologyNo.92 West-Da Zhi StreetHarbin 150001HeilongjiangChina Institute of Advanced Electrochemical Energy&School of Materials Science and Engineering Xi'an University of TechnologyXi'an 710048ShaanxiChina

A core shell structured C@MoxTi1-xO2-δnanocrystal with a functionalized interface(C@MTNC-FI)was fabricated via the hydrothermal method with subsequent annealing derived from tetrabutyl *** formation of anatase TiO2 was inhibited by the simultaneous presence of the hydrothermal etching/regrowth process,infiltration of Mo dopants and carbon coating,which endows the C@MTNC-FI with an ultrafine crystalline architecture that has a Mo-functionalized interface and carbon-coated *** Ru nanoparticles(NPs)were supported on C@MTNC-FI by employing a microwave-assisted polyol process(MAPP).The obtained Pt Ru/C@MTNC-FI catalyst has 2.68 times higher mass activity towards methanol electrooxidation than that of the un-functionalized catalyst(Pt Ru/C@TNC)and 1.65 times higher mass activity than that of Pt Ru/C catalyst with over 25%increase in *** improved catalytic performance is due to several aspects including ultrafine crystals of TiO2 with abundant grain boundaries,Mofunctionalized interface with enhanced electron interactions,and core shell architecture with excellent electrical transport *** work suggests the potential application of an interface-functionalized crystalline material as a sustainable and clean energy solution.

关键词： Interface functionalization TiO2 Nanocrystalline Mo doping Core–shell PtRu catalyst Methanol electrooxidation

Tailoring Nitrogen Terminals on MXene Enables Fast Charging and Stable Cycling Na-Ion Batteries at Low Temperature

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Nano-Micro Letters 2022年第9期14卷 63-78页

作者： Yang Xia Lanfang Que Fuda Yu Liang Deng Zhenjin Liang Yunshan Jiang Meiyan Sun lei Zhao zhenbo Wang MIIT Key Laboratory of Critical Materials Technology for New Energy Conversion and Storage State Key Lab of Urban Water Resources and EnvironmentSchool of Chemistry and Chemical EngineeringHarbin Institute of TechnologyHarbin 150001People’s Republic of China Engineering Research Center of Environment‑Friendly Functional Materials Ministry of EducationInstitute of Materials Physical ChemistryHuaqiao UniversityXiamen 361021People’s Republic of China The Institute for Advanced Studies Wuhan UniversityWuhan 430072People’s Republic of China College of Materials Science and Engineering Shenzhen UniversityShenzhen 518071People’s Republic of China

Sodium-ion batteries stand a chance of enabling fast charging ability and long lifespan while operating at low temperature(low-T).However,sluggish kinetics and aggravated dendrites present two major challenges for anodes to achieve the goal at ***,we propose an interlayer confined strategy for tailoring nitrogen terminals on Ti_(3)C_(2) MXene(Ti_(3)C_(2)-N_(funct)) to address these *** introduction of nitrogen terminals endows Ti_(3)C_(2)-N_(funct) with large interlayer space and charge redistribution,improved conductivity and sufficient adsorption sites for Na^(+),which improves the possibility of Ti_(3)C_(2) for accommodating more Na atoms,further enhancing the Na^(+) storage capability of Ti_(3)C_(2).As revealed,Ti_(3)C_(2)-N_(funct) not only possesses a lower Na-ion diffusion energy barrier and charge trans-fer activation energy,but also exhibits Na^(+)-solvent co-intercalation behavior to circumvent a high de-solvation energy barrier at ***,the solid electrolyte interface dominated by inorganic com-pounds is more beneficial for the Na^(+)transfer at the electrode/electrolyte *** with of the unmodified sample,Ti_(3)C_(2)-Nfunct exhibits a twofold capacity(201 mAh g^(-1)),fast-charging ability(18 min at 80% capacity retention),and great superiority in cycle life(80.9%@5000 cycles)at -25℃.When coupling with Na_(3)V_(2)(PO_(4))_(2)F_(3) cathode,the Ti_(3)C_(2)-N_(funct)//NVPF exhibits high energy density and cycle stability at -25℃.

关键词： Tailoring nitrogen terminals Na^(+)-solvent co-intercalation Interfacial kinetics Fast charging Low-temperature SIBs

Effect of polytetrafluoroethylene(PTFE) in current collecting layer on the performance of zinc-air battery

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Progress in Natural Science:Materials International 2020年第6期30卷 861-867页

作者： Bing Liu Yunkun Dai Lin Li Hongda Zhang lei Zhao Fanrong Kong Xulei Sui zhenbo Wang MIIT Key Laboratory of Critical Materials Technology for New Energy Conversion and Storage State Key Lab of Urban Water Resource and Environment School of Chemistry and Chemical Engineering Harbin Institute of Technology State Grid Heilongjiang Electric Power Co. Ltd. Electric Power Research Institute

Beyond reasonable designing catalysts, the optimization of preparing air cathode has far-reaching implications for the development of Zinc-air batteries. In this study, the effect of Polytetrafluoroethylene(PTFE) in current collecting layer on the performance of Zinc-air battery was investigated. The results showed that as the polytetrafluoroethylene(PTFE) content and heat treatment temperature changed, the hydrophobicity and porosity of current collecting layer also changed, thereby affecting the performance of air cathode. The air cathode assembled with PTFE-3-300 possessed an excellent electrochemical performance, which was prepared by brushing PTFE and acetylene black(wherein the mass ratio of them is 18:5) on current collecting layer and then heating at300 °C. The obtained air cathode displayed relatively small polarization loss and excellent rate performance,showing a polarization potential of-0.405 V vs. Hg/Hg O at 100 m A cm-2and the voltage retention of 94.47%from 5 to 20 m A cm-2. Besides, the air cathode displayed excellent discharge stability maintaining average potential 1.3249 V for 100 h. Based on this work, a detailed understanding of the relationship of PTFE and current collecting layer can be achieved to improve the electrode design, architecture and fabrication.

关键词： PTFE content Temperature Zinc-air batteries Current collecting layer