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面内预起拱型梁端地震损伤控制保险丝力学性能试验研究

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工程力学 2024年第6期41卷 55-65页

作者：李行张令心林旭川朱柏洁谢贤鑫中国地震局工程力学研究所地震工程与工程振动重点实验室黑龙江哈尔滨150080 地震灾害防治应急管理部重点实验室黑龙江哈尔滨150080

工程结构抗震韧性的提升是城市韧性建设的基础。研究具有“保险丝”损伤熔断、损伤可识别、易更换理念的新型结构地震损伤控制构件,对结构体系抗震韧性水准的提升具有重要价值。在前期常规平板型损伤控制保险丝研究的基础上,该文提出了... 详细信息

工程结构抗震韧性的提升是城市韧性建设的基础。研究具有“保险丝”损伤熔断、损伤可识别、易更换理念的新型结构地震损伤控制构件,对结构体系抗震韧性水准的提升具有重要价值。在前期常规平板型损伤控制保险丝研究的基础上,该文提出了一种利用面内预起拱机制进行梁柱节点损伤控制的保险丝装置。阐明了建议的结构损伤控制保险丝装置(简称保险丝)的构造与工作机理。设计了6个不同预起拱情况、不同长细比的保险丝试件,并采用拟静力加载方式对保险丝的受力机理与抗震性能进行研究。对试验结果的分析发现:与平板保险丝相比,面内预起拱型保险丝的滞回曲线更饱满,受压强度更稳定;预起拱延缓了强度退化;随着长细比减小或预起拱高度的增大,强度退化变缓;分肢转角超过0.07 rad左右时,保险丝受损导致强度逐渐下降,建议对其进行更换。力学模型计算结果与试验结果基本吻合,可估算预起拱型保险丝特征强度。

关键词：损伤控制保险丝预起拱拟静力试验力学性能损伤识别

α1-抗胰蛋白酶对未成熟脑白质损伤小鼠运动功能的影响

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中国当代儿科杂志 2024年第2期26卷 181-187页

作者：李文冬宋娟张含杨禄祥岳宇阳张新玲王永郑州大学第三附属医院小儿内科/河南省小儿脑损伤重点实验室河南郑州450052

目的探讨α1-抗胰蛋白酶(α1-antitrypsin,AAT)对未成熟脑白质损伤小鼠成年期运动功能的影响。方法将5日龄C57BL/6J幼鼠随机分为假手术组(n=27)、缺氧缺血(hypoxia-ischemia,HI)+生理盐水组(n=27)、HI+AAT组(n=27)。通过HI法建立未成熟... 详细信息

目的探讨α1-抗胰蛋白酶(α1-antitrypsin,AAT)对未成熟脑白质损伤小鼠成年期运动功能的影响。方法将5日龄C57BL/6J幼鼠随机分为假手术组(n=27)、缺氧缺血(hypoxia-ischemia,HI)+生理盐水组(n=27)、HI+AAT组(n=27)。通过HI法建立未成熟脑白质损伤小鼠模型。HI+AAT组分别于HI前24 h、HI后立即及HI后72 h腹腔注射AAT(50 mg/kg);HI+生理盐水组在相同时间腹腔注射相同剂量生理盐水。造模后7 d和55 d进行头颅磁共振T2加权成像扫描。2月龄时利用Catwalk步态分析系统评估成年期小鼠的静态、动态和协调性参数。结果与假手术组小鼠相比,HI损伤小鼠造模后7 d头颅磁共振T2加权像呈现高信号,可见脑白质明显损伤;造模后55 d脑白质损伤仍存在。与假手术组小鼠相比,HI+生理盐水组小鼠爪印面积、最大接触面积、平均压强、最大压强、爪印宽度、平均速度、身体速度、步幅长度、摆动速度、步态模式AA占比、爪印耦合(左后爪→左前爪)占比降低(P<0.05);HI+生理盐水组爪间距离、步态模式AB占比、位相滞后(左前爪→左后爪)占比升高(P<0.05)。与HI+生理盐水组小鼠相比,HI+AAT组小鼠平均速度、身体速度、步幅长度、摆动速度(右前爪)升高(P<0.05)。结论未成熟脑白质损伤小鼠在成年期可表现出明显运动功能障碍,而应用AAT可改善其部分运动功能。

关键词：缺氧缺血脑白质损伤 α1-抗胰蛋白酶 Catwalk步态分析小鼠

基于政策工具的我国健康城市行动政策文本分析

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现代预防医学 2024年第13期51卷 2417-2421页

作者：张馨凌王嘉宜杨雨婷郭蕊首都医科大学公共卫生学院

目的对健康城市行动相关政策文本进行分析，探讨政策工具现状与不足，为健康城市政策的调整优化提供依据。方法基于Rothwell&Zegveld的政策工具，针对收集到的26份政策文本构建二维框架并编码分类，对政策工具的使用情况进行频数统计... 详细信息

目的对健康城市行动相关政策文本进行分析，探讨政策工具现状与不足，为健康城市政策的调整优化提供依据。方法基于Rothwell&Zegveld的政策工具，针对收集到的26份政策文本构建二维框架并编码分类，对政策工具的使用情况进行频数统计。结果从政策工具维度看，环境型、供给型、需求型政策占比分别为57.18%、38.11%、4.72%。从健康行动维度看，全方位干预健康影响因素使用频率最高，为50.98%。在具体建设领域中，实施健康环境促进行动使用频率较高，为13.80%。结论我国健康城市现有的政策工具使用不均衡，环境型工具使用过多，需求型工具使用不足，且政策工具的内部均衡性较差。建议各地基于当地实际调整政策工具使用比例，充分发挥各类工具在健康城市行动政策中的不同作用，保障健康城市行动政策的有效落实。

关键词：健康城市政策文本政策工具政策分析

RESEARCH ON DISTRIBUTION FUNCTION AND ORIENTATION TENSORS OF FIBER SUSPENSIONS IN WEDGE-SHAPED FLOW FIELD

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Journal of Hydrodynamics 2002年第1期14卷 38-44页

作者： Lin, Jian-Zhong zhang, ling-xin Wang, Ye-Long Dept. of Mech. Zhejiang Univ. Hangzhou 310027 China

The distribution function and orientation tensor of fiber suspensions in wedge shaped flow field were computed . The results indicate that with time increasing, the fiber orient themselves to flow direction gradually. At the locations with same pole radii, the angle between fiber orientation and centerline, which occurs with the most probability, decreases with the pole angle increasing . At the locations with same pole angle, the angle between fiber orientation and centerline increases with the pole radii decreasing. The second order tensors get steady more quickly at the points where the velocity g radients are larger. At the locations with same pole angle, the steady values of orientation tensors are identical. At the locations with same pole radii is, streamline becomes flatter as the pole angle decreases.

关键词： fiber suspensions wedge shaped flow distribution function orientation tensors numerical simulation

A PRESSURE-BASED ALGORITHM FOR CAVITATING FLOW COMPUTATIONS

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Journal of Hydrodynamics 2011年第1期23卷 42-47页

作者： zhang ling-xin ZHAO Wei-guo SHAO Xue-ming Department of Mechanics State Key Laboratory of Fluid Power Transmission and Control Zhejiang UniversityHangzhou 310027 China

A pressure-based algorithm for the prediction of cavitating flows is *** algorithm employs a set of equations including the Navier-Stokes equations and a cavitation model explaining the phase change between liquid and vapor.A pressure-based method is used to construct the algorithm and the coupling between pressure and velocity is *** pressure correction equation is derived from a new continuity equation which employs a source term related to phase change rate instead of the material derivative of density Dρ/*** pressure-based algorithm allows for the computation of steady or unsteady,2-D or 3-D cavitating *** 2-D cases,flows around a flat-nose cylinder and around a NACA0015 hydrofoil,are simulated respectively,and the periodic cavitation behaviors associated with the re-entrant jets are *** algorithm shows good capability of computating time-dependent cavitating flows.

关键词： cavitating flow pressure-based algorithm cavitation model numerical simulation

Design of intelligent detecting system based on wireless transmission

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第3期8卷 490-494页

作者： GUO Li-wei LIU Dong-hui zhang xin-ling SUN Xiao-yun Department of Electrical and lnformation. Huazhong University of Science and Technology Wuhan 430074 China Department of Electrical and Information. Hebei University of Science and Technology Shijiazhuang 050054 China

An intelligent detecting system based on wireless transmission is designed. Its hardware includes the card reading module, the wireless digital transmission module, the LCD module, the random password keyboard module and a 16×16 lattice word database based on e-Flash MM36SB020. Its software is a communication protocol between the central control computer and the entrance management base station. To resolve the conflicting problems occurred during the data transmission, a method of delaying time at random is proposed.

关键词： Communication protocol Delaying time Random entrance management base station Random password keyboard Wireless digital transmission

Automated Identification of Ordered Phases for Simulation Studies of Block Copolymers

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Chinese Journal of Polymer Science 2024年第5期42卷 683-692,I0011页

作者： Yu-Chen zhang Wei-ling Huang Yi-xin Liu State Key Laboratory of Molecule Engineering of Polymers Department of Macromolecular ScienceFudan UniversityShanghai200433China

In unit cell simulations,identification of ordered phases in block copolymers(BCPs)is a tedious and time-consuming task,impeding the advancement of more streamlined and potentially automated research *** this study,we propose a scattering-based automated identification strategy(SAIS)for characterization and identification of ordered phases of BCPs based on their computed scattering *** approach leverages the scattering theory of perfect crystals to efficiently compute the scattering patterns of periodic morphologies in a unit *** the first stage of the SAIS,phases are identified by comparing reflection conditions at a sequence of Miller *** confirm or refine the identification results of the first stage,the second stage of the SAIS introduces a tailored residual between the test phase and each of the known candidate ***,our strategy incorporates a variance-like criterion to distinguish background species,enabling its extension to multi-species BCP *** has been demonstrated that our strategy achieves exceptional accuracy and robustness while requiring minimal computational ***,the approach allows for real-time expansion and improvement to the candidate phase library,facilitating the development of automated research workflows for designing specific ordered structures and discovering new ordered phases in BCPs.

关键词： Block copolymer Phase identification Scattering function

NUMERICAL SIMULATION OF CAVITATION FLOW UNDER HIGH PRESSURE AND TEMPERATURE

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Journal of Hydrodynamics 2011年第3期23卷 289-294页

作者： ZHAO Wei-guo zhang ling-xin SHAO Xue-ming Department of Mechanics Zhejiang University Hangzhou 310027 China State Key Laboratory of Fluid Power Transmission and Control Zhejiang University Hangzhou 310027 China

The numerical simulation of cavitation flow on a 2D NACA0015 hydrofoil under high pressure and temperature is performed. The Singhal＇s cavitation model is adopted combined with an improved RNG k-ε turbulence model to study the cavitation flow. The thermal effect in the cavitation flow is taken into account by introducing the energy equation with a source term based on the latent heat transfer. The code is validated by a case of a hydrofoil under two different temperatures in a comparison between the simulation and the experiment. Computational results show that the latent heat of vaporization has a significant impact on the cavitation process in the high temperature state, and the cavity in the high temperature state is thinner and shorter than that in a normal state with the same cavitation number, due to the fact that the heat absorption in the cavitation area reduces the local temperature and the saturated vapor pressure. This numerical study provides some guidance for the design of machineries in the High Pressure and Temperature （HPT） state.

关键词： cavitation NACA0015 thermodynamic CFD high pressure and temperature

Involvement of CD4^＋CD25^＋ regulatory T cells in the pathogenesis of polycythaemia vera

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Chinese Medical Journal 2008年第18期 1781-1786页

作者： ZHAO Wen-bo LI Ying LIU xin zhang ling-yan WANG xin Department of Hematology Shandong Provincial Hospital Affiliated to Shandong University Jinan Shandong 250021 China

Background Regulatory T cells （mreg） have been shown to play an important role in the regulation of hematopoietic activity. However, there is no information about the effect of Treg cells in the pathogenesis of polycythaemia vera （PV）. Methods In this study, we investigated the percentage and function of Treg cells in the peripheral blood of 21 PV patients and 25 healthy donors, mreg cells were identified and characterized as CD4^＋CD25^＋FOXP3^＋ by flow cytometry. The suppressive activity of CD4^＋CD25^＋ Treg cells was assessed by the proliferation and cytokine secretion of the co-cultured CD4^＋CD25^- fractions. Results The results showed that the percentage of Treg cells in the peripheral blood of PV patients significantly increased compared to healthy controls （（10.93±4.02）% vs （5.86±1.99）%, P 〈0.05）. Moreover, the mRNA and protein expression of FOXP3 was higher in CD4^＋CD25^＋ Treg cells. Coordinately, when co-cultured with the activated CD4^＋CD25^- cells, the CD4^＋CD25^＋ Treg cells showed enhanced suppressive function in PV. Yet, the underlying mechanism for the increased frequency and function of CD4^＋CD25^＋ Treg cells is still to be clarified. Conclusion Treg cells expansion might account for the abnormal T cell immunity in PV patients and thus contribute to the pathogenesis of PV.

关键词： polycythaemia vera regulatory T cells pathogenesis