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哈氏系统破坏的微观结构分析 总被引:1,自引:0,他引:1
本文旨在通过五个长骨试样在五个不同载荷等级(2KN,3KN,4KN,5KN和6KN)的抗压试验,观察哈氏系统(Haversian System)——哈氏骨板和哈氏管——的变化情况.由一组显微照片可以十分清晰地看出:(1)在载荷等级低的情况(2KN),哈氏管几乎与未受力时一样,哈氏骨板亦然;(2)在载荷等级高的情况,哈氏骨板最弱的部分最先变形;(3)随着载荷的增加,哈氏系统破坏的形式十分复杂,断裂总是发生在骨的结合缘处. 同时,测量了变形后的哈氏骨板和哈氏管的有关尺寸.对试验中所观察到的现象,用线性粘弹性力学的理论予以解释.最后提出了骨单位为纤维增强的厚壁筒模型. 相似文献
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由J.F.V.Vincent和J.D.Currey主编的《生物材料的力学性能》(The Mechanical Properties of Biological Materials),是1979年9月4—6日在Leeds大学召开的实验生物学学会第34届讨论会的论文集,其中论文18篇,墙报11篇。文集的特点是题材广泛,内容丰富,论点新颖。它包括了迄今为止已经知道的植物和动物的全部领域,例如,从粘液到毛发,从蜗牛的触角、昆虫的表皮到软骨、骨和海贝类动物。因此,这本论文集是生物力学家和材料科学家感兴趣的。除两位编者合写的序言外,论文的题目是:生物力学:生命学说的最后一个堡垒(J.E.Gordon);断裂(E.H.Andrews);复合材料的力学性能(B.Harris); 相似文献
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中国力学学会常务理事杨桂通教授主持了这次会议。中国力学学会副理事长、西北工业大学校长季文美教授在开幕式上讲了话,中国生物医学工程学会副秘书长胡良俊同志参加了会议。会议共有正式代表43名,列席代表16名。会议邀请报告7篇:可变形体力学的基本方程(杨桂通),线性粘弹性力学(孙家驹),骨的超微结构(耿介),骨力学的基本问题(白详),骨力学的应用(顾志华),生物软组织力学(王公瑞),骨的生长和压电性(钱民全)。 相似文献
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本文用摄动法导出了弦的非线性振动的K-dV方程,讨论了只有耗散和色散的特殊情况,然后详细讨论了K-dV方程的孤波解的性态,并给出了弦的非线性振动孤波的主要特征。 相似文献
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Dynamic ana1ysis of the viscoelastic simple supporteJ beam has beenmade in accordance with the re lationship between stre ss and strain expressedby the simplest Voigt mechanical mode1,from which several analytic ex-pressions have been obtained.It is shown that the reduction of the ratio of natural frequencips peog-resses with the increase of the exciting frequency for high modes(Tab.l).1n the final part of this paper,the forced vibration oL simple supportedbeam subjected to a random and harmonic excitation has also been dealt with,and the repre sentations of the beam defIection have been derived. 相似文献
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The aim of this paper is to observe variations in the mechanical properties of Haversian systems including Haversian lamellae and canals, by means of the compressive test of five bone specimens subjected to different loads corresponding to 2KN, 3KN, 4KN, 5KN and 6KN respectively. From a series of related microscopic pictures it is clearly seen that: (1) in the lower level of loading (2KN). the Haversian canals much the same as the one unsubjected to loads, and conditions of Harversian lamellae are also the same, but, the individual Harversian canal was slightly bent; (2) in the case of the higher levels of loading, it is first deformed in the weaked portion of the Haversian lamellae; (3) with increasing loads, the fracture shapes of the Haversian sgstem are very complex, but the fractures always take place in the cement line between osteon s. At the same time, deformed dimensions of the Harversian lamellae and canals were measured. The observed phenomena were quaiitatively interpreted by the theory of t 相似文献
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将弹性介质 的几何和运动非线性方程简化成具有电磁场中的Born-Infeld方程的形式,并证明了该方程的类孤波解的存在. 相似文献
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In this study, compressive tests of the bones along the axial direction have been carried out on some wet specimens of the right femur and humerus, from which there have been obtained the elastic modulus of femur E=9.98×109N/mM2 and.’that of humerus E=11.37×109N/m2 Also comparisons and discussions have been made with reference to the available data reported abroad and at home.As indicated in this paper, bone tissues obviously possess viscoelastic properties. Their hysteresis loops are shown in Fig. 3 far and (b) and some mechanical phenomena observed during the test are illustrated elsewhere. 相似文献