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西北工业大学学报 2001年第2期19卷 209-211页

作者：陈国定 h haiser W haas G Lechner 西北工业大学机械工程系陕西西安710072 斯图加特大学机械零件研究所德国斯图加特70569

利用大型有限元软件 MARC/ MENTAT32 0研究了动态接触条件下 ,表面粗糙效应对动力密封摩擦副接触性态的影响 ,揭示了动态接触条件下若干表面粗糙形貌参数对密封系统工作性能的影响。

关键词：密封粗糙度动态接触有限元法表面粗糙效应数值模拟

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密封系统性能的表面粗糙效应试验研究

机械工程学报 2000年第6期36卷 30-32页

作者：陈国定 haiser h haas W Lechner G 西北工业大学机械系西安710072 斯图加特大学

分析了密封系统中硬对偶件表面粗糙特性对密封系统工作性能的影响，揭示了在相对运动密封零件表面间摩擦学过程中出现的微观曲路密封效应和微观跑合效应，为通过控制密封系统中硬对偶件表面加工工艺以形成优秀的表面形貌，来提高密封系... 详细信息

分析了密封系统中硬对偶件表面粗糙特性对密封系统工作性能的影响，揭示了在相对运动密封零件表面间摩擦学过程中出现的微观曲路密封效应和微观跑合效应，为通过控制密封系统中硬对偶件表面加工工艺以形成优秀的表面形貌，来提高密封系统的工作性能提供了新的思路和概念。

关键词：表面粗糙效应密封系统硬对偶件

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O形密封圈的有限元力学分析

机械科学与技术 2000年第5期19卷 740-741,744页

作者：陈国定 haiser h haas W Lechner G 西北工业大学西安710072 斯图加特大学

采用大型有限元分析程序 MARC/ Mentat32 0对 O形密封圈在“安装”状态和密封流体介质作用下的力学性能进行了分析 ,研究了造成密封圈撕裂损坏及材料松弛的当量 Cauchy应力峰值大小及位置随密封流体介质作用的变化情况 ,以及轴和密封接... 详细信息

采用大型有限元分析程序 MARC/ Mentat32 0对 O形密封圈在“安装”状态和密封流体介质作用下的力学性能进行了分析 ,研究了造成密封圈撕裂损坏及材料松弛的当量 Cauchy应力峰值大小及位置随密封流体介质作用的变化情况 ,以及轴和密封接触面间的接触压力及剪应力分布状态。为重要场合下 O形密封圈的正确选用提供了一种方法。

关键词： O形密封圈有限元分析力学性能数学模型

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阶梯组合密封件的力学性能研究

机械科学与技术 2000年第6期19卷 920-922页

作者：陈国定 haiser h haas W Lechner G 西北工业大学西安710072 斯图加特大学机械零件研究所斯图加特70569

采用大型有限元分析软件 MARC/ Mentat32 0 ,分析了阶梯组合密封件 (阶梯形密封 +O形密封圈 )截面上的当量 Von Mises应力分布 ,使用三种不同硬度 O形密封圈的阶梯组合密封件在不同工况下的径向力、密封接触区宽度及摩擦功耗。所获得的... 详细信息

采用大型有限元分析软件 MARC/ Mentat32 0 ,分析了阶梯组合密封件 (阶梯形密封 +O形密封圈 )截面上的当量 Von Mises应力分布 ,使用三种不同硬度 O形密封圈的阶梯组合密封件在不同工况下的径向力、密封接触区宽度及摩擦功耗。所获得的计算结果对于阶梯组合密封件的设计及使用都是非常有意义的。

关键词：阶梯密封有限元 O形密封圈组合密封力学性能

动力密封接触表面粗糙效应的有限元分析——静态接触有限元模拟

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西北工业大学学报 2001年第1期19卷 136-139页

作者：陈国定 h.haiser W.haas G.Lechner 西北工业大学机械工程系陕西西安710072 斯图加特大学机械零件研究所斯图加特70569

利用大型有限元软件 MARC/MENTAT32 0研究了静态接触条件下表面粗糙效应对密封摩擦副接触性态的影响 ,揭示了若干表面粗糙形貌参数对涉及磨损寿命和摩擦功耗等密封系统工作性能的这种接触性态的影响规律 ,为提高动力密封系统的工作品质... 详细信息

利用大型有限元软件 MARC/MENTAT32 0研究了静态接触条件下表面粗糙效应对密封摩擦副接触性态的影响 ,揭示了若干表面粗糙形貌参数对涉及磨损寿命和摩擦功耗等密封系统工作性能的这种接触性态的影响规律 ,为提高动力密封系统的工作品质提供了有意义的结果。

关键词：动力密封表面粗糙效应有限元方法静态接触

硬对偶件表面加工工艺对密封系统性能影响的试验研究

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流体机械 2000年第3期28卷 12-13页

作者：陈国定 h.haiser W.haas G.Lechner 西北工业大学斯图加特大学

采用试验手段 ,研究了密封系统中硬对偶件表面加工工艺及方法对密封系统性能的影响 ,揭示了这种影响的程度及规律。

关键词：密封系统硬对偶件表面加工工艺工作性能

Dynamic stress concentration in an infinitely long cylindrical cavity due to a point spherical source embedded within a fluid-saturated poroelastic formation of infinite extent

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Applied Mathematics and Mechanics(English Edition) 2025年第1期46卷 139-156页

作者： h.hOSSEINI O.BALILAShAKI Department of Mechanical Engineering Faculty of EngineeringGolestan University

The effects of a harmonically exciting monopole source on an infinitely long cylindrical cavity embedded entirely within a fluid-saturated poroelastic formation of infinite extent are examined theoretically. It is assumed that the source is located outside the cavity at a specified distance from the borehole axis. The magnitudes of the hoop and radial stresses beside the pore pressures exerted on the interface and inside the porous medium surrounding the borehole are calculated and discussed. Biot's poroelastic modeling along with three types of boundary conditions for the cylindrical interface including the ideal fluid, empty borehole, and rigid inclusion with a hard boundary is employed for the analysis. Utilizing a proper translational addition theorem for expressing the incident spherical wave in terms of cylindrical wave expansions, the proposed boundary conditions at the interface are satisfied. Stresses are formulated by means of wave potential functions in a three-dimensional(3D) manner. The effects of the frequency and the radial distance between the source and borehole on the induced stresses are examined for the first cylindrical modes over frequency spectra. Two permeability conditions for the interface and three types of soils for the porous formation are considered throughout the analysis. To give an overall outline of the study, a numerical example is presented. The results clearly indicate that the distance is a key parameter and has considerable effects on the induced stress values. In addition, the interface permeability condition and soil characteristics play an important role in determining the dynamic response of the borehole. Finally,the obtained results are compared with the relevant analyses existing in the literature for some limit cases, and good agreement is achieved.

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Neuroinflammation as a therapeutic target in huntington's disease

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Neural Regeneration Research 2025年第3期20卷 817-818页

作者： Andrea Kwakowsky Thulani h.Palpagama Center for Brain Research and Department of Anatomy and Medical Imaging Faculty of Medical and Health SciencesUniversity of AucklandAucklandNew Zealand Pharmacology and Therapeutics School of MedicineGalway Neuroscience CentreUniversity of GalwayGalwayIreland

In 1872, George huntington presented his essay “On Chorea” to the Meigs and Mason Academy of Medicine and, in doing so, detailed a disease that would later bear his name. huntington's disease(hD) is a genetic, neurodegenerative disease that manifests as the loss of motor control,cognitive impairment,and mood and psychiatric changes in paents.

关键词： huntington inflammation Medicine

Glial response in the midcingulate cortex in huntington’s disease

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Neural Regeneration Research 2025年第1期20卷 207-208页

作者： Thulani h.Palpagama Andrea Kwakowsky Center for Brain Research and Department of Anatomy and Medical Imaging Faculty of Medical and Health SciencesUniversity of AucklandAucklandNew Zealand Pharmacology and Therapeutics School of MedicineGalway Neuroscience CenterUniversity of GalwayGalwayIreland

huntington’s disease(hD)is a genetic disease characterized by the progressive degeneration of the striatum and *** can present with a variety of symptoms that can broadly be classified into motor symptoms,inclusive of choreatic movements and rigidity,mood and psychiatric symptoms,such as depression and apathy,and cognitive symptoms,such as cognitive *** causal mutation underlying hD results from an expansion of a CAG repeat sequence on the IT15 gene,resulting in the formation and accumulation of a mutant huntingtin protein.

关键词： huntington degeneration cortex

Does mesenchymal stem cell’s secretome affect spinal sensory circuits?Implication for pain therapies

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Neural Regeneration Research 2025年第1期20卷 181-183页

作者： Francesco Ferrini Esri h.Juárez Adalberto Merighi Department of Veterinary Sciences University of TurinGrugliascoTOItaly Department of Psychiatry and Neuroscience UniversitéLavalQuébec CityQCCanada

Mesenchymal stem cells(MSCs)are multipotent adult stem cells of mesodermal origin that can be isolated from various tissues,including bone marrow,tooth pulp,adipose tissue,and umbilical *** have gained significant attention in regenerative medicine due to their ability to modulate the immune system and favor tissue *** enrich the medium in which they are cultivated with a broad range of bioactive molecules,including growth factors,cytokines,chemokines,enzymes,nucleic acids,and extracellular vesicles that collectively compose the MSC *** increasing number of pre-clinical studies suggest that delivering in vivo an MSC-conditioned medium(i.e.,the medium collected from MSC cultures after at least 3 days of exposure)exerts neuroprotective and anti-inflammatory effects in a variety of neurological conditions.

关键词： protective clinical collective