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腾冲地震台老洋河观测站水管倾斜仪干扰分析

高原地震 2024年第1期36卷 27-31页

作者：张山元熊家伟段胜朝方伟云南省地震局腾冲地震台云南腾冲679100 云南省地震局云南昆明650224

腾冲地震台老洋河观测站DSQ型水管倾斜仪观测曲线南北向和东西向自2023年1月底以来偶尔出现小幅台阶。通过对此异常出现的干扰因素进行排查,认为此类台阶是由水管倾斜仪钵体内胶水脱落部分溶解于水造成。此类异常特点主要表现为:异常前... 详细信息

腾冲地震台老洋河观测站DSQ型水管倾斜仪观测曲线南北向和东西向自2023年1月底以来偶尔出现小幅台阶。通过对此异常出现的干扰因素进行排查,认为此类台阶是由水管倾斜仪钵体内胶水脱落部分溶解于水造成。此类异常特点主要表现为:异常前期水管倾斜仪观测曲线偶尔出现小幅台阶;异常中后期台阶幅度和出现频率都逐渐增加。通过清理水体杂质能减少台阶出现频率,但不能根本解决,清洗钵体后更换水体才能彻底消除台阶。

关键词：水管倾斜仪腾冲地震台干扰分析钵体水质

腾冲台YRY-4分量钻孔应变仪资料可靠性及同震响应特征浅析

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防灾减灾学报 2024年第2期40卷 51-56,68页

作者：张山元曾庆堂段胜朝番绍辉李圣腾冲地震台云南腾冲679100 云南省地震局云南昆明650224

通过对腾冲台钻孔应变近五年(2017年1月-2022年3月)观测日均值进行自检曲线分析,认为其观测资料稳定、数据真实可靠。对数据干扰源进行总结归纳,得出影响钻孔应变数据变化的主要干扰因素分别为放水蓄水干扰、降雨干扰、气压突变干扰与... 详细信息

通过对腾冲台钻孔应变近五年(2017年1月-2022年3月)观测日均值进行自检曲线分析,认为其观测资料稳定、数据真实可靠。对数据干扰源进行总结归纳,得出影响钻孔应变数据变化的主要干扰因素分别为放水蓄水干扰、降雨干扰、气压突变干扰与重型机械施工干扰等。对腾冲台钻孔应变数据资料进行同震响应分析,结果表明:该测项资料同震响应良好,与地震波形记录有较好的对应性。

关键词：钻孔应变同震响应特征分析腾冲台

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宽胸气雾剂通过调控TLR4/MyD88/NLRP3/Caspase-1通路减轻心梗诱导的大鼠心肌细胞损伤

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浙江中医药大学学报 2024年第1期48卷 122-130页

作者：王乙连何晨晨张珊苑韦琛谊褚剑锋福建中医药大学中西医研究院福州350122 福建省中西医结合老年性疾病重点实验室福建中医药大学陈可冀学术思想传承工作室

[目的]探索宽胸气雾剂(Kuanxiong aerosol,KXA)对异丙肾上腺素(isoproterenol,ISO)诱导的心肌梗死(myocardial infarction,MI)大鼠心肌炎症和细胞焦亡的影响,并分析其对焦亡关键通路Toll样受体4(Toll-like receptor 4,TLR4)/髓样分化因子(myeloid differentiation primary response gene 88,MyD88)/NOD样受体热蛋白结构域相关蛋白3(NOD-like receptor pyrin domain containing 3,NLRP3)/胱天蛋白酶-1(cysteinyl aspartate specific proteinase-1,caspase-1)的作用。[方法]按体质量将30只雄性Wistar大鼠随机分为5组:对照组(0.9%氯化钠溶液)、模型组(ISO 120 mg·kg^(-1))、单硝酸异山梨酯组(ISO 120 mg·kg^(-1)+单硝酸异山梨酯5 mg/kg·d)、KXA低剂量组(ISO 120 mg·kg^(-1)+KXA 0.1 mL/kg·d)和KXA高剂量组(ISO 120 mg·kg^(-1)+KXA 0.3 mL/kg·d),每组6只,连续灌胃14 d,并在第13、14天腹腔注射ISO。末次干预结束后,麻醉采血、分离心脏,以酶联免疫吸附试验(enzyme-linked immunosorbent assay,ELISA)检测各组血清肌酸激酶同工酶(creatine kinase-MB,CK-MB)和心肌肌钙蛋白T(cardiac troponin T,cTnT)水平,以及血清白细胞介素-6(interleukin-6,IL-6)、白细胞介素-18(interleukin-18,IL-18)、白细胞介素-1β(interleukin-1β,IL-1β)和肿瘤坏死因子-α(tumor necrosis factor-α,TNF-α)水平;苏木精-伊红(hematoxylin-eosin,HE)染色检测心肌病理变化;转录组测序分析各组心肌基因表达差异;免疫印迹检测焦亡通路相关蛋白的表达情况。[结果]与对照组比较,模型组cTnT和CK-MB检测显著升高,差异具有统计学意义(P<0.01),表明MI大鼠模型构建成功。HE染色显示,KXA和单硝酸异山梨酯干预后心肌纤维排列断裂、紊乱情况明显减轻。转录组测序显示,对照组和模型组之间存在2646个差异基因;模型组和KXA组之间存在714个差异基因,进一步分析发现130个基因表达上调,7个基因表达下调,其中炎症相关性通路TLR4通路被显著富集。与模型组比较,KXA高剂量组、KXA低剂量组和单硝酸异山梨酯组血清IL-6、IL-18、IL-1β和TNF-α表达显著减少,差异具有统计学意义(P<0.01,P<0.05)。免疫印迹显示,模型组TLR4、MyD88、磷酸化核因子-κB p65(phospho-nuclear factor-κB,p-NF-κB)p65、NLRP3、切割的胱天蛋白酶-1(cleaved caspase-1)和消皮素D蛋白N端结构域(Gasdermin D-N,GSDMD-N)表达显著高于对照组;而KXA高剂量组、KXA低剂量组和单硝酸异山梨酯组的表达显著低于模型组(P<0.05,P<0.01)。[结论]KXA可以改善心肌缺血,减轻心脏损伤,抑制心肌细胞焦亡和炎症反应,其机制可能与调节TLR4/MyD88/NLRP3/caspase-1信号通路有关。

关键词：宽胸气雾剂心肌梗死焦亡炎症 TLR4 NLRP3

NONLINEAR WAVES AND PERIODIC SOLUTION IN FINITE DEFORMATION ELASTIC ROD

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Acta Mechanica Solida Sinica 2006年第1期19卷 1-8页

作者： Liu Zhifang zhang shanyuan Institute of Applied Mechanics Taiyuan University of Technology Taiyuan 030024 China

A nonlinear wave equation of elastic rod taking account of finite deformation, transverse inertia and shearing strain is derived by means of the Hamilton principle in this paper. Nonlinear wave equation and truncated nonlinear wave equation are solved by the Jacobi elliptic sine function expansion and the third kind of Jacobi elliptic function expansion method. The exact periodic solutions of these nonlinear equations are obtained, including the shock wave solution and the solitary wave solution. The necessary condition of exact periodic solutions, shock solution and solitary solution existence is discussed.

关键词： nonlinear wave finite deformation Poisson effect Jacobi elliptic function

Dynamic Buckling of Column Impacted by a Rigid Body

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上海交通大学学报 2004年第Z2期38卷 120-123页

作者： Zhijun Han Hongwei Ma shanyuan zhang Institute of Applied Mechanics Taiyuan University of TechnologyTaiyuan 030024 China Institute of Applied Mechanics Taiyuan University of TechnologyTaiyuan 030024 China Institute of Applied Mechanics Taiyuan University of TechnologyTaiyuan 030024 China

The dynamic buckling of an elastic column subjected to axial impact by a rigid body is discussed in accordance with the energy law in this paper. The equation of lateral disturbance used to analysis the problem is developed by taking into account the effect of stress wave. The power series solution of this problem has been obtained by using the power series approach. The buckling criterion of this problem is proposed by analyzing the characteristics of the solution. The relationships between critical velocity and impacting mass as well as critical velocity and critical length are given by using theoretical analysis and numerical computation.

关键词： dynamic buckling column stress wave critical criteria power series solution

NONLINEAR FLEXURAL WAVES IN LARGE-DEFLECTION BEAMS

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Acta Mechanica Solida Sinica 2009年第4期22卷 287-294页

作者： shanyuan zhang Zhifang Liu Guoyun Lu Institute of Applied Mechanics Taiyuan University of Technology Taiyuan 030024 China

The equation of motion for a large-deflection beam in the Lagrangian description are derived using the coupling of flexural deformation and midplane stretching as a key source of nonlinearity and taking into account the transverse, axial and rotary inertia effects. Assuming a traveling wave solution, the nonlinear partial differential equations are then transformed into ordinary differential equations. Qualitative analysis indicates that the system can have either a homoclinic orbit or a heteroclinic orbit, depending on whether the rotary inertia effect is taken into account. Furthermore, exact periodic solutions of the nonlinear wave equations are obtained by means of the Jacobi elliptic function expansion. When the modulus of the Jacobi elliptic function m→1 in the degenerate case, either a solitary wave solution or a shock wave solution can be obtained.

关键词： large-deflection beam nonlinear flexural wave Jacobi elliptic function expansion

THE GLOBAL DEFORMATION AND LOCAL DAMAGE ANALYSIS OF FILLED METALLIC CYLINDRICAL SHELLS IMPACTED BY MISSILES

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Acta Mechanica Solida Sinica 1999年第3期12卷 255-262页

作者： Li Zhu zhang shanyuan Yang Guitong Taiyuan Univ Technol Inst Appl Mech Taiyuan 030024 Peoples R China

A group of theoretical models has been developed for analyzingtransient dynamic re- sponse to filled metallic cylindrical shellsimpacted by flat-nosed missiles at normal obliquity on the ba- sis ofthe analogy modeling method of beam-on-foundation. It can be used forsolving the global defor- mation and the local failure of cylindricalshells in the impact process. the ballistic limit speed and im- pactresponse history have been calculated by this group of theoreticalmodels, and the inner pressure effect on the ballistic limit speedand some parameters are discussed at length.

关键词： missiles filled metallic cylindrical shells perforation

DENTING AND FAILURE OF LIQUID-FILLED TUBES UNDER LATERAL IMPACT

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Acta Mechanica Solida Sinica 2012年第6期25卷 609-615页

作者： Guoyun Lu Jianping Lei Zhijun Han Zhifang Liu shanyuan zhang Institute of Applied Mechanics Taiyuan University of Technology

In this paper, numerical simulation of impact cases of liquid-filled tube impacted by missiles is conducted with a commercial finite element code LS-DYNA, and the results obtained are compared with the experimental data to verify the validity of the numerical simulation model adopted. With the verified numerical method, the processes of dynamic response of a blunt indenter impacting an empty or liquid-filled three-span continuous tubular beam are studied when the parameter such ms the indenter＇s mass, liquid＇s density or impact velocity is varied and the other conditions are kept the same. The simulation results indicate that the criticM perforation energy and the deformation of the wall of the pipe are significantly influenced by the presence of the liquid and the pressure. The liquid filling the tube provides a ＇foundation＇ pressure to resist and localize the deformation, which may affect the perforation process and lead to a reduction of the ballistic limit. The simulation results also indicate that the increase of the fluid density filled in the tube will decrease the ballistic limit, but the fluid density must be in some scope. The relationship between the ballistic limit velocity of the tube and the mass of the impact missile is nonlinear in the Cartesian coordinate while it becomes linear through logarithmic transformation.

关键词： impact perforation fluid-structure interaction tube

THE DYNAMIC BUCKLING OF ELASTIC-PLASTIC COLUMN SUBJECTED TO AXIAL IMPACT BY A RIGID BODY

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Acta Mechanica Solida Sinica 2005年第3期18卷 256-264页

作者： Han Zhijun Wang Jingchao Cheng Guoqiang Ma Hongwei zhang shanyuan Institute of Applied Mechanics Taiyuan University of Technology Taiyuan 030024 China

The dynamic buckling of an elastic-plastic column subjected to axial impact by a rigid body has been discussed in this paper. The whole traveling process of elastic-plastic waves under impact action is analyzed with the characteristics method. The regularity of stress changes in both column ends and the first separating time of a rigid body and column are obtained. By using the energy principle and taking into account the propagation and reflection of stress waves the lateral disturbance equation is derived and the power series solution is given. In addition, the critical buckling condition can be obtained from the stability analysis of the solution. By numerical computation and analysis, the relationship among critical velocity and impact mass, hardening modulus, and buckling time is given.

关键词： dynamic buckling stress wave critical criteria power series solution