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兔动脉粥样硬化易损斑块模型的建立

基础医学与临床 2005年第4期25卷 370-374页

作者：仲琳张运张梅季哓平陈文强姚桂华丁士芳张鹏飞山东大学齐鲁医院心内科山东济南250012

目的利用血管内超声(IVUS)的影像学特点分析建立的兔模型的易损斑块。方法16只雄性新西兰纯种兔,通过球囊损伤腹主动脉和高脂(1%胆固醇)饲料喂养8周,建立动脉粥样硬化易损斑块的兔模型。应用IVUS分别测量腹主动脉同一血管段中多个病变... 详细信息

目的利用血管内超声(IVUS)的影像学特点分析建立的兔模型的易损斑块。方法16只雄性新西兰纯种兔,通过球囊损伤腹主动脉和高脂(1%胆固醇)饲料喂养8周,建立动脉粥样硬化易损斑块的兔模型。应用IVUS分别测量腹主动脉同一血管段中多个病变部位及其参考部位的各项指标,然后给予中国斑点蝰蛇毒(CRVV)和组胺药物触发,造成实验性斑块破裂和血栓形成。结果破裂与未破裂斑块相比较,破裂斑块具有较大的偏心性(P<0.05),破裂斑块呈现明显的正性重构,而未破裂斑块主要表现为负性重构。结论IVUS应用于已建立的动脉粥样硬化易损斑块的动物模型上,能够准确地识别动脉粥样硬化易损斑块,为以后实验性大样本研究药物稳定易损斑块的治疗奠定了基础。

关键词：动脉粥样硬化易损斑块腹主动脉 IVUS 血管内超声大样本研究特点分析球囊损伤病变部位血栓形成斑块破裂主要表现动物模型兔模型实验性未破裂影像学新西兰胆固醇蝰蛇毒偏心性药物重构

Multiplicity of Homoclinic Solutions for Second Order Hamiltonian Systems with Local Conditions at the Origin

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Acta Mathematica Sinica,English Series 2022年第4期38卷 735-744页

作者： peng LIU fei GUO School of Mathematics Tianjin UniversityTianjin 300354P.R.China Tianjin Key Laboratory of Brain-Inspired Intelligence Technology Tianjin 300354P.R.China

In this paper,the multiplicity of homoclinic solutions for second order non-autonomous Hamiltonian systemsü(t)-L(t)u(t)+▽uW(t,u(t))=0 is obtained via a new Symmetric Mountain Pass Lemma established by Kajikiya,where L∈C(R,RN×N)is symmetric but non-periodic,W∈C1(R×RN,R)is locally even in u and only satisfies some growth conditions near u=0,which improves some previous results.

关键词： Second order non-autonomous Hamiltonian systems Homoclinic solutions multiplicity new symmetric mountain pass lemma

Multiplicity of Periodic Solutions for Second Order Hamiltonian Systems with Asymptotically Quadratic Conditions

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Acta Mathematica Sinica,English Series 2020年第1期36卷 55-65页

作者： peng LIU fei GUO School of Mathematics Tianjin University

A class of second order non-autonomous Hamiltonian systems with asymptotically quadratic conditions is considered in this *** Fountain Theorem,one multiplicity result of periodic solutions is obtained,which improves s... 详细信息

关键词： Second order Hamiltonian systems asymptotically quadratic conditions Fountain Theorem periodic solution multiplicity

ASSOCIATION BEHAVIOR OF PORPHYRIN PENDANTS IN pH-SENSITIVE WATER-SOLUBLE POLYMER

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Chinese Journal of Polymer Science 2012年第1期30卷 63-71页

作者： Ke—wei Ding fei Wang fei-peng Wu Technical Institute of Physics and Chemistry Chinese Academy of Sciences Beijing 100190 China Graduate University of Chinese Academy of Sciences Beijing 100049 China

A novel tripyridylporphyrin monomer,5-[4-[2-（acryloyloxy）ethoxy]phenyl]-10,15,20-tris（4-pyridyl）porphyrin （TrPyP）,was synthesized and polymerized with acrylamide（AM） to prepare the hydrophobically associating water-soluble polymer *** aggregation behavior of porphyrin pendants was investigated by UV-Visible and fluorescence *** polymer displays a strong tendency of hydrophobic association even in dilute *** increasing the concentration,the maximum absorption wavelength of Soret band changes from 416 nm to 407 nm,and the fluorescence corrected for the inner filter effect exhibits moderate concentration *** the results indicate thatπ-πinteraction of porphyrin pendants plays a key role in association of PAM-TrPyP,and H-aggregates of porphyrins are mainly formed in the concentrated *** the other hand,dynamic light scattering（DLS） and transmission electron microscopy（TEM） were used to follow the changes in size and structure of the macromolecular assemblies with the concentration *** polymer aggregation conformation changes from loose ＂vesicle-like＂ morphology to solid globule *** pH value of solution decreases to 4.3,pyridine moieties on porphyrin pendants could be protonated and the H-aggregates formed in macromolecular matrix are destroyed by electrostatic repulsion interactions.

关键词： Porphyrin Water-soluble polymer π-πInteractions H-aggregate pH-sensitivity

Influence of Solid Rocket Motor Slag on the Space Debris Environment

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Journal of Harbin Institute of Technology(New Series) 2013年第6期20卷 15-20页

作者： Bao-Jun Pang Ke-Ke peng Wei-Ke Xiao fang-fei Ju Dong-fang Wang Hypervelocity Impact Research Center Harbin Institute of Technology Harbin 150080 China Dept. Astronautical Engineering Harbin Institute of Technology Harbin 150001 China

The resulting slag particles from solid rocket motor( SRM) firings are an important component of space debris environment. Slag sizes as large as 1 cm have been witnessed in ground tests,and comparable sizes have been also estimated via observations of sub-orbital tail-off events. We achieve slag initial data based on MASTER slag model and SRM historical launch data,and propagate slag long-term orbital evolution taking into account the zonal harmonics J2,atmospheric drag,solar radiation pressure and luni-solar attraction to discuss the slag size distribution and orbital characteristics. Finally,future slag debris environment is evaluated based on two different launch rate assumptions. The result shows that current launch frequency will make the slag population sustain growth and the population will not decrease at once even if there are no more launches in the future.

关键词： solid rocket motor slag space debris orbital distribution spatial densityCLC number:V51 Document code:AArticle ID:1005-9113(2013)06-0015-06

Entropy-expansiveness of Geodesic Flows on Closed Manifolds without Conjugate Points

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Acta Mathematica Sinica,English Series 2016年第4期32卷 507-520页

作者： fei LIU fang WANG College of Mathematics and System Science Shandong University of Science and Technology Qingdao 266590 P. R. China School of Mathematical Sciences Capital Normal University Beijing 100048 P. R. China Beijing Center for Mathematics and Information Interdisciplinary Sciences (BCMIIS) Beijing 100048 P. R. China

In this article,we consider the entropy-expansiveness of geodesic flows on closed Riemannian manifolds without conjugate *** prove that,if the manifold has no focal points,or if the manifold is bounded asymptote,then the geodesic flow is ***,for the compact oriented surfaces without conjugate points,we prove that the geodesic flows are *** also give an estimation of distance between two positively asymptotic geodesics of an uniform visibility manifold.

关键词： Entropy-expansiveness geodesic flows manifolds without conjugate points

Existence of Three Solutions for Quasilinear Elliptic Equations: an Orlicz-Sobolev Space Setting

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Acta Mathematicae Applicatae Sinica 2017年第2期33卷 287-296页

作者： fei fang Zhong TAN Department of Mathematics Beijing Technology and Business University School of Mathematical Sciences Xiamen University

In this paper, we establish the existence of three weak solutions for quasilinear elliptic equations in an Orlicz-Sobolev space via an abstract result recently obtained by Ricceri in [13].

关键词： Orlicz-Sobolev spaces quasilinear elliptic equations three critical points theorem

Simulating Eastern-and Central-Pacific Type ENSO Using a Simple Coupled Model

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Advances in Atmospheric Sciences 2018年第6期35卷 671-681页

作者： Xianghui fang fei ZHENG Institute of Atmospheric Sciences Fudan University International Center for Climate and Environment Science (ICCES) Institute of Atmospheric PhysicsChinese Academy of Sciences Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Nanjing University of Information Science and Technology

Severe biases exist in state-of-the-art general circulation models（GCMs） in capturing realistic central-Pacific（CP） El Nino structures. At the same time, many observational analyses have emphasized that thermocline（TH） feedback and zonal advective（ZA） feedback play dominant roles in the development of eastern-Pacific（EP） and CP El Nino-Southern Oscillation（ENSO）, respectively. In this work, a simple linear air-sea coupled model, which can accurately depict the strength distribution of the TH and ZA feedbacks in the equatorial Pacific, is used to investigate these two types of El Nino. The results indicate that the model can reproduce the main characteristics of CP ENSO if the TH feedback is switched off and the ZA feedback is retained as the only positive feedback, confirming the dominant role played by ZA feedback in the development of CP ENSO. Further experiments indicate that, through a simple nonlinear control approach, many ENSO characteristics,including the existence of both CP and EP El Nino and the asymmetries between El Nino and La Nina, can be successfully captured using the simple linear air-sea coupled model. These analyses indicate that an accurate depiction of the climatological sea surface temperature distribution and the related ZA feedback, which are the subject of severe biases in GCMs, is very important in simulating a realistic CP El Nino.

关键词： central-Pacific El Nino eastern-Pacific El Nino simple coupled model simulation asymmetry

A Novel Fractional Plastic Damage Model for Quasi-brittle Materials

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Acta Mechanica Solida Sinica 2021年第5期34卷 706-717页

作者： peng-fei Qu Qi-Zhi Zhu Key Laboratory of Ministry of Education for Geomechanics and Embankment Engineering Hohai UniversityNanjing210098China College of Civil and Transportation Engineering Hohai UniversityNanjing210098China

In this work,a novel constitutive model is developed within the framework of fractional plasticity to delineate the coupling between inelastic deformation and damage of quasi-brittle *** with the common challenge of determining plastic flow direction,we resort herein to the Riemann–Liouville definition of fractional derivatives,instead of introducing an additional plastic *** pre-peak hardening behavior is described using an exponential function,while the post-peak softening response is viewed as the consequence of material *** describing damage evolution,a damage criterion is constructed in terms of plastic volume dilation related to micro-crack *** is conducive to supply a new insight for describing the complex influence of the non-orthogonality of plastic flow on damage *** numerical applications,a semi-implicit return mapping algorithm is *** predictive performance of the model is evaluated by comparing numerical simulations with experimental data under various loading paths.

关键词： Quasi-brittle materials Fractional plasticity Damage Dilatancy Numerical algorithm