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粘土滑体运动特性及变形解体数值模拟 被引量:1
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作者 彭国园 周海清 《后勤工程学院学报》 2017年第2期14-22,共9页
为分析粘土滑体下滑中的运动特性及变形解体规律,编写PFC3D颗粒流程序,建立滑体沿滑面、坡面及水平面运动的数值模型,模拟滑体失稳后运动的全过程。将滑体试样划分为前段、中段、后段3个部分,通过对3段滑体中部和侧部上下层位置滑体颗... 为分析粘土滑体下滑中的运动特性及变形解体规律,编写PFC3D颗粒流程序,建立滑体沿滑面、坡面及水平面运动的数值模型,模拟滑体失稳后运动的全过程。将滑体试样划分为前段、中段、后段3个部分,通过对3段滑体中部和侧部上下层位置滑体颗粒的速度、运动中滑体的微裂隙发展情况及滑体运动中各能量的变化情况进行追踪,观测分析滑体的运动状态及变形解体随时间的演化过程,结果表明:滑体的运动速度与滑体的位置有关,主要是因为在运动过程中滑体会受到其他滑体的影响;滑体的变形解体在运动中会一直发生,通常在滑体的运动状态发生剧烈改变时解体程度最大。 展开更多
关键词 粘土滑坡 运动过程 变形解体 PFC3D 数值模拟
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Singularity-free expression of magnetic field of cuboid under undulating terrain 被引量:4
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作者 匡星涛 杨海 +1 位作者 朱晓颖 李伟 《Applied Geophysics》 SCIE CSCD 2016年第2期238-248,416,共12页
Most of the current computing methods used to determine the magnetic field of a uniformly magnetized cuboid assume that the observation point is located in the upper half space without a source. However, such methods ... Most of the current computing methods used to determine the magnetic field of a uniformly magnetized cuboid assume that the observation point is located in the upper half space without a source. However, such methods may generate analytical singularities for conditions of undulating terrain. Based on basic geomagnetic field theories, in this study an improved magnetic field expression is derived using an integration method of variable substitution, and all singularity problems for the entire space without a source are discussed and solved. This integration process is simpler than that of previous methods, and final integral results with a more uniform form. AT at all points in the source-flee space can be calculated without requiring coordinate transformation; thus forward modeling is also simplified. Corresponding model tests indicate that the new magnetic field expression is more correct because there is no analytical singularity and can be used with undulating terrain. 展开更多
关键词 Undulating terrain magnetic field of cuboid variable substitution analytical singularity
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Morphology and survival of cryopreserved-thawed ovarian tissues after heterotopic autotransplantation
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作者 Rumana Jafarey Jing Yang 《The Chinese-German Journal of Clinical Oncology》 CAS 2014年第3期110-114,共5页
Objective: The aim of our study was to observe the survival and morphological changes of thawed ovarian tis- sues after heterotopic transplantation. Methods: Twenty SPF-SD female rats (5-6 weeks old) were equally ... Objective: The aim of our study was to observe the survival and morphological changes of thawed ovarian tis- sues after heterotopic transplantation. Methods: Twenty SPF-SD female rats (5-6 weeks old) were equally randomized into the control group and experimental group. In control group, the freshly isolated ovaries were fixed in formalin. In experimental group, the freshly isolated ovaries were vitrified immediately and cut into thin slices. After stored in liquid nitrogen for 21 days, the tissues of experimental group were rapidly thawed and transplanted into back muscles of rats for 2 or 4 weeks, respectively. After that, all rats in experimental group were sacrificed and the ovarian tissues were collected and fixed in 4% formaldehyde solution. Then the ovarian tissues were stained with HE and observed under the light confocal microscope. Re- suits: With the naked eyes, there was no specific alteration except the size reduction with color changing. Under microscopy, we found normal cortex and medulla in the ovary, and the primordial follicles and follicles in various stages were observed in the cortex. The normal oocytes in ovarian tissues of experimental group were significant decreased than in the control group. Conclusion: The ovarian tissues survive well in experimental group and there is no significant difference in the proportion of follicles between different times (2 and 4 weeks) after grafting. Our results suggest that thawed ovarian tissues could survive after heterotopic transplantation into back muscles of rat models and maintain their morphology and function. 展开更多
关键词 ovarian tissue MORPHOLOGY heterotopic transplantation thawing
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Soliton Solutions, Bcklund Transformations and Lax Pair for a(3 + 1)-Dimensional Variable-Coefficient Kadomtsev–Petviashvili Equation in Fluids
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作者 王云坡 田播 +4 位作者 孙文荣 甄慧玲 江彦 孙亚 解西阳 《Communications in Theoretical Physics》 SCIE CAS CSCD 2014年第5期551-557,共7页
Under investigation in this paper is a (3 q- 1)-dimensional variable-coefficient Kadomtsev-Petviashvili equation, which describes the propagation of surface and internal water waves. By virtue of the binary Bell pol... Under investigation in this paper is a (3 q- 1)-dimensional variable-coefficient Kadomtsev-Petviashvili equation, which describes the propagation of surface and internal water waves. By virtue of the binary Bell polynomials, symbolic computation and auxiliary independent variable, the bilinear forms, soliton solutions, Backlund transformations and Lax pair are obtained. Variable coefficients of the equation can affect the solitonic structure, when they are specially chosen, while curved and linear solitons are illustrated. Elastic collisions between/among two and three solitons are discussed, through which the solitons keep their original shapes invariant except for some phase shifts. 展开更多
关键词 (3 1)-dimensional variable-coefficient Kadomtsev-Petviashvili equation soliton solutions B^cklund transformations symbolic computation
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