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Earthquake Engineering and Engineering Vibration 2021年第3期20卷 605-620页

作者： Xie Qiang Wu zhi-Hui Dong Jie Zhong shuai School of Civil Engineering Chongqing UniversityChongqing 400045China College of Civil Engineering Hebei University of ArchitectureZhangjiakou 075000China

This paper presents a comparative analysis of ground vibration in three directions generated by a heavy-duty railway with various track *** vibration characteristics in the plane area were investigated by using matrix test *** peak attenuation was faster within 25 m from the embankment,and the high-frequency vibration attenuates faster with increased *** the cutting section with multi-stage soil slope,decay rate of acceleration was relatively *** acceleration level of the plane region ranged to 82.2-89.1 dB by the single C80 *** the acceleration level caused by the C80 trains running parallel after meeting showed a distinct *** increment of the cutting section was much larger compared with the embankment section,with the increment ranging from 1.2-2.5 *** terms of the cutting section,Y direction acceleration was dominant closer to the *** 10-30 m of the track,the Y direction acceleration(perpendicular to the rail)decreased rapidly and became comparable to the X direction(parallel to the rail)and Z ***,the cutting case generated a higher level of vibration in all three directions compared to the embankment,but as the distance from track increased,the deviation between acceleration gradually decreased.

关键词： heavy-duty railway different track sections field measurement vibration response characteristics cutting slope

Firing rates of coupled noisy excitable elements

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Frontiers of physics 2014年第1期9卷 120-127页

作者： shuai Liu zhi-Wei He Meng Zhan Wuhan Center for Magnetic Resonance State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics Wuhan Institute of Physics and Mathematics Chinese Academy of Sciences Wuhan 430071 China University of the Chinese Academy of Sciences Beijing 100049 China

The dynamics of coupled excitable FitzHugh Nagumo systems under external noisy driving is studied. Different from most of previous work focusing on the noise-induced regularity in the framework of coherence resonance, here the average frequency （or firing rate） of coupled excitable elements is of much more concern. We find that （i） their frequencies first increase and then decrease with the increase of the coupling, and there is a clear crossover from a rush increase to a smooth increase with the increase of noise strength, and （ii） for nonidentical cases, all elements transit to an identical frequency simultaneously only after a certain coupling strength is achieved. These first-increase-thendecrease non-monotonic frequency behavior and isochronous frequency synchronization are believed to be two basic behaviors in coupled noisy excitable systems.

关键词： coupled excitable elements firing rate noise coherence resonance

Dynamic simulation of double-cased perforation in deepwater high temperature and high-pressure oil and gas wells

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Petroleum Science 2024年第5期21卷 3482-3495页

作者： gang Bi Fei Han Jie-Min Wu Pei-Jie Yuan shuai-shuai Fu Ying Ma Shaanxi Key Laboratory of Well Stability and Fluid&Rock Mechanics in Oil and Gas Reservoirs Xi'an Shiyou UniversityXi'an710065ShaanxiChina College of Petroleum Engineering Xi'an Shiyou UniversityXi'an710065ShaanxiChina

In order to ensure the penetrability of double-cased perforation in offshore oil and gas fields and to maximize the capacity of perforation completion, This study establishes a dynamic model of double-cased perforation using ANSYS/LS-DYNA simulation technology. The combination of critical perforation parameters for double casing is obtained by studying the influencing factors of the jet-forming process,perforation depth, diameter, and stress changes of the inner and outer casing. The single-target perforation experiments under high-temperature and high-pressure(HTHP) conditions and ground full-scale ring target perforation tests are designed to verify the accuracy of numerical simulation results. The reduced factor is adopted as the quantitative measure of perforation depth and diameter for different types of perforation charge under different conditions. The results show that the perforation depth reduction increases with temperature and pressure, and the reduced factor is between 0.67 and 0.87 under HTHP conditions of 130℃/44 MPa and 137℃/60 MPa. Comparing the results of the numerical simulation and the full-scale test correction, the maximum error is less than 8.91%, and this numerical simulation has strong reliability. This research provides a basis for a reasonable range of double-cased perforation parameters and their optimal selection.

关键词： Deepwater HTHP Double-cased perforation Optimization of perforation parameters Dynamic simulation Full-scale perforation simulation

骨桥蛋白和p38MAPK信号通路在多房棘球蚴原头节发育中的作用

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动物医学进展 2025年第1期46卷 9-15页

作者：徐刚毛艺胡帅葛宇飞徐志张玉梦谢士伟张宏伟张示杰石河子大学第一附属医院新疆石河子832000 石河子大学医学院新疆石河子832000

为明确骨桥蛋白(OPN)和多房棘球蚴(Echinococcus multilocularis,Em)p38丝裂原活化蛋白激酶(p38MAPK)信号通路在Em发育过程的作用,剖检感染Em 4~6月的长爪沙鼠,提取Em原头节后,分别用不同浓度的p38MAPK抑制剂(SB202190)处理Em原头节,选... 详细信息

为明确骨桥蛋白(OPN)和多房棘球蚴(Echinococcus multilocularis,Em)p38丝裂原活化蛋白激酶(p38MAPK)信号通路在Em发育过程的作用,剖检感染Em 4~6月的长爪沙鼠,提取Em原头节后,分别用不同浓度的p38MAPK抑制剂(SB202190)处理Em原头节,选取合适的SB202190浓度后在体外将原头节分为DMSO组、anti-p38MAPK组、PBS组、OPN组、OPN+anti-p38MAPK组,采用伊红染色、caspase-3试剂盒检测caspase-3、EDU和Hoechst染色、活性氧(ROS)检测探针检测原头节的活性、凋亡和增殖情况。结果显示,抑制Em的SB202190适宜浓度为20μmol/L,SB202190增加Em的伊红染色率、caspase-3水平,减少EDU阳性、ROS水平,OPN可减少Em伊红染色率、caspase-3水平,增加EDU阳性率、ROS水平,且SB202190可逆转OPN对Em的结果,这些结果表明SB202190可抑制Em的活性和增殖、促进凋亡并与浓度正相关,而OPN可促进Em的活性和增殖、抑制凋亡,且SB202190可逆转OPN对Em的作用。研究结果为OPN和p38MAPK信号通路可能成为治疗多房棘球蚴病的新分子靶点提供证据。

关键词：多房棘球蚴多房棘球蚴病骨桥蛋白 p38丝裂原活化蛋白激酶

Time-variant fragility analysis of the bridge system considering time-varying dependence among typical component seismic demands

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Earthquake Engineering and Engineering Vibration 2019年第2期18卷 363-377页

作者： Song shuai Qian Yongjiu Liu Jing Xie Xiaorui Wu gang Department of Civil Engineering Taiyuan University of Technology Department of Bridge Engineering Southwest Jiaotong University Department of Environmental Science Baylor University Southwest Municipal Engineering Design and Research Institute of China School of Civil Engineering and Architecture East China Jiaotong University

This paper presents a copula technique to develop time-variant seismic fragility curves for corroded bridges at the system level and considers the realistic time-varying dependence among component seismic demands. Based on material deterioration mechanisms and incremental dynamic analysis, the time-evolving seismic demands of components were obtained in the form of marginal probability distributions. The time-varying dependences among bridge components were then captured with the best fitting copula function, which was selected from the commonly used copula classes by the empirical distribution based analysis method. The system time-variant fragility curves at different damage states were developed and the effects of time-varying dependences among components on the bridge system fragility were investigated. The results indicate the time-varying dependence among components significantly affects the time-variant fragility of the bridge system. The copula technique captures the nonlinear dependence among component seismic demands accurately and easily by separating the marginal distributions and the dependence among them.

关键词： system fragility chloride corrosion time-varying dependence copula function probabilistic seismic demand

Global Asymptotics of Orthogonal Polynomials Associated with a Generalized Freud Weight

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Chinese Annals of Mathematics,Series B 2018年第3期39卷 553-596页

作者： zhi-Tao WEN Roderick WONG shuai-Xia XU Department of Mathematics Taiyuan University of TechnologyTaiyuan 030024China Liu Bie Ju Centre for Mathematical Sciences City University of Hong KongHong KongChina Institut Franco-Chinois de l’Energie Nucleaire Sun Yat-sen UniversityGuangzhou 510275China

In this paper, the authors consider the asymptotic behavior of the monic polynomials orthogonal with respect to the weight function w（x） = /x/2αe-（x4＋tx2）, x ∈R, where α is a constant larger than - 1/2 and t is any real number. They consider this problem in three separate cases：（i） c 〉 -2, （ii） c = -2, and （iii） c 〈 -2, where c ：= tN-1/2 is a constant, N = n ＋ a and n is the degree of the polynomial. In the first two cases, the support of the associated equilibrium measure μ is a single interval, whereas in the third case the support of μt consists of two intervals. In each case, globally uniform asymptotic expansions are obtained in several regions. These regions together cover the whole complex plane. The approach is based on a modified version of the steepest descent method for Riemann-Hilbert problems introduced by Deift and Zhou （1993）.

关键词： Orthogonal polynomials Globally uniform asymptotics Riemann-Hilbertproblems The second Painlev6 transcendent Theta function

Hydrodynamic performances and wakes induced by a generic submarine operating near the free surface in continuously stratified fluid

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Journal of Hydrodynamics 2023年第3期35卷 396-406页

作者： Liu-shuai Cao gang Gao En-kai Guo De-cheng Wan School of Naval Architecture Ocean and Civil EngineeringShanghai Jiao Tong UniversityShanghai 200240China

The wake of a submarine is a crucial element that greatly affects its stealth and hydrodynamic *** investigate the propagation and evolution characteristics of submarine wakes in a stratified fluid,particularly under free surface conditions,a numerical method to simulate the linearly stratified environment was developed.A thermocline model based on Boussinesq assumption was introduced to match the continuously stratified *** volume of fluid(VOF)method was utilized to capture free surface waves,while a fully structured grid and the SST k-ωturbulence model were combined to solve the complex flow of *** independence study in homogenous flow near the free surface was initially ***,the hydrodynamic performance,wake evolution characteristics,free surface signatures as well as decay of velocity under different stratification levels were *** demonstrated that the numerical method employed was efficient in simulating stratified ***,it showed that density stratification had a significant impact on the hydrodynamics and wake characteristics of a submarine,especially under strong density stratification circumstances.

关键词： Wakes submarine free surface stratified fluid hydrodynamics

Neuropeptide Y and melanocortin receptors in fish:regulators of energy homeostasis

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Marine Life Science & Technology 2022年第1期4卷 42-51页

作者： zhi-shuai Hou Hai-Shen Wen Key Laboratory of Mariculture(Ocean University of China) Ministry of Education(KLMME)Fisheries CollegeOcean University of ChinaQingdao266003China

Energy homeostasis,which refers to the physiological processes that the energy intake is exquisitely coordinated with energy expenditure,is critical for ***,multiple and complex mechanisms have been involved in the regulation of energy *** central melanocortin system plays an important role in modulating energy *** system includes the orexigenic neurons,expressing neuropeptide Y/Agouti-related protein(NPY/AgRP),and the anorexigenic neurons expressing proopiomelanocortin(POMC).The downstream receptors of NPY,AgRP and post-translational products of POMC are G protein-coupled receptors(GPCRs).This review summarizes the compelling evidence demonstrating that NPY and melanocortin receptors are involved in energy ***,the comparative studies on physiology and pharmacology of NPY and melanocortin receptors in humans,rodents and teleosts are ***,we provide a strategy demonstrating the potential application of the new ligands and/or specific variants of melanocortin system in aquaculture.

关键词： Energy homeostasis Neuropeptide Y receptors Melanocortin receptors GPCRs Fish(Teleost)

Synthesis of dimethyl adipate from cyclopentanone and dimethyl carbonate over solid base catalysts

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Science China Chemistry 2012年第3期55卷 380-385页

作者： WU DuDu CHEN zhi JIA ZhenBin shuai Li School of Pharmacy Guangdong Medical CollegeDongguan 523808China School of Pharmacy South Central University for NationalitiesWuhan 430074China

A facile route for the synthesis of dimethyl adipate （DAP） from cyclopentanone and dimethyl carbonate （DMC） in the pres- ence of solid base catalysts has been developed. It was found that the intermediate carbomethoxycyclopentanone （CMCP） was produced from cyclopentanone with DMC in the first step, and then CMCP was further converted to DAP by reacting with a methoxide group. The role of the basic catalysts can be mainly ascribed to the activation of cyclopentanone via the abstraction of a proton in the a-position by base sites, and solid bases with moderate strength, such as MgO, favor the formation of DAP.

关键词： dimethyl adipate cyclopentanone dimethyl carbonate solid base catalysts

Effects of rare earth elements on microstructure and tensile properties of Al-Si-Cu alloy at 250℃

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China Foundry 2021年第5期18卷 474-480页

作者： shuai-bo Zhang Yong Su Wen-gang Gong School of Materials Science and Engineering Hefei University of TechnologyHefei 230009China

The effects of rare earth elements(La,Sm)on the high-temperature(250℃)microstructure and mechanical properties of Al-Si-Cu alloys were *** experimental results show that with the addition of La and Sm,theα-Al was significantly refined,and the eutectic Si changed from acicular to rod-like and *** and SEM analysis shows that the rare earth phases in the alloy were mainly AlSiRe and *** morphology observations show the fracture mode of the alloy changes from brittle and ductile fracture to ductile *** the increase of La or Sm contents,the mechanical properties of the alloys at 250℃ increase at first,and then *** the contents of La and Sm are 0.4wt.%and 0.2wt.%,the tensile strength of the alloy reaches maximum of 143.91 MPa and 201.48 MPa,respectively.

关键词： Al-Si-Cu rare earth element microstructure mechanical properties high-temperature stretching