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液化夹层对浅基础结构隔震响应的影响

土木与环境工程学报（中英文） 2025年第1期47卷 46-53页

作者：胡记磊沈文翔杨兵三峡大学三峡库区地质灾害教育部重点实验室湖北宜昌443002 三峡大学土木与建筑学院湖北宜昌443002

砂土液化夹层既会造成地基失效破坏,又会对上部建筑起到减震作用,而覆盖层可以减小建筑沉降,却会放大地震作用,因此,有必要探讨结构与土相互作用下液化夹层和覆盖层对建筑的隔震耦合影响。基于Biot两相饱和多孔介质动力耦合理论,采用有... 详细信息

砂土液化夹层既会造成地基失效破坏,又会对上部建筑起到减震作用,而覆盖层可以减小建筑沉降,却会放大地震作用,因此,有必要探讨结构与土相互作用下液化夹层和覆盖层对建筑的隔震耦合影响。基于Biot两相饱和多孔介质动力耦合理论,采用有限元和有限差分耦合动力分析方法,分析不同地震强度、砂土密实度d_(r)和液化层厚深比K(考虑液化夹层和覆盖层耦合作用)对上部结构隔震的影响。结果表明:结构加速度反应谱比随震动强度增加先减小后趋于稳定,当震动强度超过某阈值时,液化层隔震效果不再增加;松砂(d_(r)=30%)的隔震效果优于中密砂(d_(r)=50%)和密砂(d_(r)=70%),但会产生不可忽略的沉降危害;密砂虽然能更好地抑制建筑沉降量,但在短周期内会起到加震作用;考虑覆盖层和液化层的耦合作用,发现K值在0.3~0.5区间内时,既能减小建筑沉降,又能起到减隔震作用。

关键词：液化夹层浅基础隔震基础沉降数值模拟

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Effects of corner modifications on wind loads and local pressures on walls of tall buildings

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Building Simulation 2021年第4期14卷 1109-1126页

作者： K.t.tse Gang hu Jie Song Hyo Seon Park Bubryur Kim department of Civil and Environmental Engineering Hong Kong University of Science and TechnologyClear Water BayKowloonHong KongChina School of Civil and Environmental Engineering Harbin Institute of TechnologyShenzhen518055China Engineering Research Center of Urban disasters Prevention and Fire Rescue technology of hubei Province School of Civil EngineeringWuhan UniversityWuhan430072China department of Architectural Engineering Yonsei UniversitySeoul120-749R.O.Korea department of Architectural Engineering Kyungil UniversityGyeongbukR.O.Korea

In this st.d., the aerodynamic characteristics of tall buildings with corner modifications (e.g., local wind force coefficients, mean pressure distributions, normalized power spectrum density, and extreme local pressure) were examined. Wind tunnel experiments were conduct.d.to measure the wind pressures on building models with different heights and recessed corners of different ratios. At a wind direction of a = 0° (i.e., wind blowing on the front of a building), corner modifications effectively reduced wind forces in all cases. Specifically, small corner modification ratios reduced wind forces more effectively than their larger counterparts. However, corner modifications result.d.in extreme local pressure on building surfaces. In addition, for small corner modification ratios, the probability of extreme local pressure occurring at a = 0° was high. this probability was also high for large corner modification ratios at a = 15° (i.e., wind blowing slightly obliquely on the front of a building) because wind blowing obliquely creates substantial vortex shedding on one side surface and extreme negative pressure over one building side surface. Results of computational fluid dynamic modeling were adopt.d.to determine details of the aerodynamic characteristics of tall buildings with corner modifications.

关键词： tall building aerodynamic modification local pressure extreme local wind loads proper orthogonal decomposition computational fluid dynamics

Creep-induced redistribution of alloying elements in CZ1 zirconium alloys

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Journal of Materials Science & technology 2024年第6期173卷 31-44页

作者： W.t.Lin Q.Y.Lv d.Jiao L.B.Zhang J.tan G.Sha J.hu China Nuclear Power technology Research Institute Shenzhen 518026China School of Material Science and Engineering Nanjing University of Science and TechnologyNanjing 210094China

Introducing minor alloying elements is an effective strategy to improve the corrosion and mechanical properties of zirconium alloys for nuclear *** in-reactor service,external environment and stress can affect the distribution of alloying elements,substantially changing the degradation process of zirconium *** date,there is a lack of in-depth understanding of the interaction between creep and microchemistry ***,we conduct.d.systematic transmission electron microscopy(tEM)and atom probe tomography(APt)investigations to address creep-induced redistribution of alloying elements in CZ1(Zr-Sn-Nb-Fe-Cr-Cu)zirconium alloy with different initial ***,Fe,Sn,and Cu are found to co-segregate at grain *** higher the intermediate annealing temperature,the larger the Gibbsian interfacial excesses of solute elements *** further demonstrate that creep can reduce the excess value of Fe at grain boundaries due to the coarsening of Zr-Fe-Cr second phase particles via grain boundary and dislocation pipe *** the same time,the excess value of Sn is increased by diffusing from the matrix to grain ***,Cu as a minor element in the concentration range of 0.05-0.3 wt.%is found to segregate at.d.slocations to form the Cottrell atmosphere and develop Cu-rich nanoclusters for suppressing dislocation *** new understanding of the segregation and clustering of minor alloying elements provides guidance for developing zirconium alloys with enhanced creep resistance.

关键词： Zirconium alloy thermal creep Grain boundary segregation dislocation segregation Cu-rich nanoclusters

云南秋海棠挥发物抗微生物活性的研究(英文)

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云南植物研究 2005年第4期27卷 437-442页

作者：管开云 Fershalova t.d. tsybulya N.V. 田代科中国科学院昆明植物研究所云南昆明650204 俄罗斯科学院西伯利亚中央植物园新西伯利亚630090

对云南产的16种秋海棠属(BegoniaL.)植物进行了挥发物抗微生物活性实验,其中14种秋海棠为首次报道。结果表明,在所研究的16种秋海棠中,有8种秋海棠具有抗葡萄球菌(Staphyllococcusepidermidis)活性。而抗大肠杆菌(Escherichiacoli)活性... 详细信息

对云南产的16种秋海棠属(BegoniaL.)植物进行了挥发物抗微生物活性实验,其中14种秋海棠为首次报道。结果表明,在所研究的16种秋海棠中,有8种秋海棠具有抗葡萄球菌(Staphyllococcusepidermidis)活性。而抗大肠杆菌(Escherichiacoli)活性最强的是厚壁秋海棠(***),假厚叶秋海棠(***)和秋海棠(***.)。只有铁甲秋海棠(***.)和毛叶秋海棠(***.)对白假丝酵母菌(Candidaalbicans)有抗性。作为室内盆栽花卉被广泛应用的秋海棠,不仅可以美化室内环境,而且还可以作为药用和净化室内环境的生态产品进行推广应用。

关键词：秋海棠抗微生物活性

Mesoporous SiO_2 Nanoparticles:A Unique Platform Enabling Sensitive detection of Rare Earth Ions with Smartphone Camera

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Nano-Micro Letters 2018年第4期10卷 3-9页

作者： Xinyan dai Kowsalya d.Rasamani Feng hu Yugang Sun department of Chemistry Temple University

Fast and sensitive detection of dilute rare earth species still represents a challenge for an on-site survey of new resources and evaluation of the economic value. In this work, a robust and low-cost protocol has been developed to analyze the concentration of rare earth ions using a smartphone camera. the success of this protocol relies on mesoporous silica nanoparticles(MSNs) with large-area negatively charged surfaces, on which the rare earth cations(e.g., Eu^(3+)) are efficiently adsorbed through electrostatic attraction to enable a ‘‘concentrating effect''. the initial adsorption rate is as fast as 4025 mg(g min)^(-1), and the adsorption capacity of Eu^(3+)ions in the MSNs is as high as 4730 mg g^(-1)(equivalent to ～41.2 M) at 70 °C. the concentrat.d.Eu^(3+)ions in the MSNs can form a complex with a light sensitizer of 1,10-phenanthroline to significantly enhance the characteristic red emission of Eu^(3+)ions due to an ‘‘antenna effect'' that relies on the efficient energy transfer from the light sensitizer to the Eu^(3+)*** positive synergy of ‘‘concentrating effect'' and ‘‘antenna effect'' in the MSNs enables the analysis of rare earth ions in a wide dynamic range and with a detection limit.d.wn to ～80 nM even using a smartphone camera. Our results highlight the promise of the protocol in fieldwork for exploring valuable rare earth resources.

关键词： Mesoporous silica nanoparticles Rare earth ions Quantitative detection Antenna effect

Experimental investigation on the wake interference among wind turbines sit.d.in atmospheric boundary layer winds

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Acta Mechanica Sinica 2017年第4期33卷 742-753页

作者： W.tian A.Ozbay X.d.Wang H.hu School of Aeronautics and Astronautics Shanghai Jiao Tong University department of Aerospace Engineering Iowa State University School of Energy Power and Mechanical Engineering North China Electric Power University

We examined experimentally the effects of incoming surface wind on the turbine wake and the wake interference among upstream and downstream wind turbines sit.d.in atmospheric boundary layer（ABL） winds. the experiment was conduct.d.in a large-scale ABL wind tunnel with scaled wind turbine models mount.d.in different incoming surface winds simulating the ABL winds over typical offshore/onshore wind farms. Power outputs and dynamic loadings acting on the turbine models and the wake flow characteristics behind the turbine models were quantified. the results revealed that the incoming surface winds significantly affect the turbine wake characteristics and wake interference between the upstream and downstream turbines. the velocity deficits in the turbine wakes recover faster in the incoming surface winds with relatively high turbulence levels. Variations of the power outputs and dynamic wind loadings acting on the downstream turbines sit.d.in the wakes of upstream turbines are correlat.d.well with the turbine wakes characteristics. At the same downstream locations, the downstream turbines have higher power outputs and experience greater static and fatigue loadings in the inflow with relatively high turbulence level, suggesting a smaller effect of wake interference for the turbines sit.d.in onshore wind farms.

关键词： turbulence winds upstream downstream turbine simulating turbulent averaged faster fatigue

St.d. ON tHE FINItE ELEMENt NUMERICAL SIMULAtION OF SHEEt MEtAL FORMING

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Acta Metallurgica Sinica(English Letters) 2004年第3期17卷 299-302页

作者： J.L.Song d.J.hu Z.L.Chang t.Y.Li Z.B.Jiang School of Mechanical Engineering Shanghai Jiaotong University Shanghai 200030 China department of Materials Engineering Taiyuan Heavy Machinery Institute Taiyuan 030024 China

Based on the Finite Element theory of Rigid Plastic,relevant problems during plas-tic simulation on sheet metal forming were technologically st.d.ed and simplified;a simplified model of the blank holder during the drawing process was established and the effects of relat.d.parameters on the forming processes were also *** the same time,a finite--element numerical simulation program SPId was *** distribution of strain and relationship of stress--stroke simulat.d.were compared with experiment.d.the results are well coincided with each *** is verified that the analytical program is reliable.

关键词： sheet metal forming finite-element numerical simulation

Microstructural Stability of a Single Crystal Superalloy dd8 during thermal Exposure

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Journal of Materials Science & technology 2008年第1期24卷 127-130页

作者： K.Y.Cheng d.H.Kim Y.S.Yoo C.Y.Jo t.Jin Z.Q.hu Superalloydivision Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China High temperature Materials Group KIMS Changwon Korea Materials test and Characterization Group KIMS Changwon Korea

Microstructural stability of a nickel base single crystal alloy dd8 has been *** heat treat.d.specimen showed good microstructural stability at 950℃.While under the as-cast condition,a kind of rod-like phase precipitat.d.in the interdendritic region of as-cast specimen during thermal *** phase,which has bcc structure,was enriched with ***-calc also predict.d.precipitation of a bcc phase at around 950℃.the Cr-rich bcc phase was considered asα-Cr and formed due to the segregation of Cr under the as-cast condition.

关键词： dd-8 Single crystal alloy Microstructural stability Alpha chromium

低负荷血流限制和高强度抗阻运动对男性运动青年大腿微循环功能的影响

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中国组织工程研究 2025年第2期29卷 393-401页

作者：彭永胡江平朱欢湖北民族大学体育学院湖北省恩施市445000 广西民族师范学院体育学院广西壮族自治区崇左市532200

背景:微循环作为人体物质能量代谢交换的唯一场所,与人体运动能力密切相关。抗阻运动是提高微循环功能的有效方式,但也有研究指出血流限制训练也能提高微循环功能,且具有负荷小和安全性高等优点。目的:比较6周低负荷血流限制运动、高强... 详细信息

背景:微循环作为人体物质能量代谢交换的唯一场所,与人体运动能力密切相关。抗阻运动是提高微循环功能的有效方式,但也有研究指出血流限制训练也能提高微循环功能,且具有负荷小和安全性高等优点。目的:比较6周低负荷血流限制运动、高强度抗阻运动对运动型男性青年大腿微循环功能的影响,并从血管内皮功能角度探讨运动改善微循环功能的可能机制。方法:将湖北民族大学60名体育专业男性大学生按照随机数表法分为对照组、高强度抗阻运动组和低负荷血流限制运动组,每组20人。低负荷血流限制运动组进行6周(每周3次、每次90 min、运动强度为30%1RM)的低负荷血流限制运动;高强度抗阻运动组进行6周(每周3次、每次90 min、运动强度为70%1RM强度)的抗阻训练;对照组该时间段不进行任何形式的运动训练。分别在干预开始的前1 d以及6周干预结束后次日的晨起空腹状态下对3组受试者微血管血流灌注量、经皮氧分压、肌氧饱和度、一氧化氮、内皮型一氧化氮合酶、内皮素1、血管内皮细胞生长因子及大腿围、肌力等指标进行测试。结果与结论:①运动干预后,低负荷血流限制运动组和高强度抗阻运动组的微血管血流灌注量加热值、血细胞移动速度加热值与对照组及运动干预前相比有显著差异(P<0.05);低负荷血流限制运动组微血管血流灌注量加热值、血细胞移动速度加热值与高强度抗阻运动组相比有显著差异(P<0.05);经皮氧分压和肌氧饱和度与干预前相比有显著性差异(P<0.05)。②运动干预后,低负荷血流限制运动组和高强度抗阻运动组一氧化氮、内皮型一氧化氮合酶、内皮素1、血管内皮细胞生长因子与对照组及运动干预前相比有显著差异(P<0.05)。③运动干预后,低负荷血流限制运动组和高强度抗阻运动组大腿围和大腿肌肉力量与运动干预前相比有显著差异(P<0.05)。④上述结果证实,6周低负荷血流限制运动和高强度抗阻运动可能通过调节内皮型一氧化氮合酶、内皮素1、血管内皮细胞生长因子等血管因子的分泌,提高体育专业大学生大腿微循环功能,并增加大腿肌肉的收缩力量,且低负荷血流限制运动对微血管血流灌注量、血细胞移动速度的干预效果更佳,因此低负荷血流限制运动较高强度抗阻运动在提高微循环功能方面更具优势。

关键词：低负荷血流限制高强度抗阻微循环功能肌肉力量微血管血流灌注量经皮氧分压肌氧饱和度一氧化氮内皮素1 血管内皮生长因子