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21.
本文研究了具有线弹簧弱界面的异质球形夹杂的本征应变问题,所采用的线弹簧界面模型既能界面的切线方向滑动,又能考虑界面的法线方向张开,根据叠加原理、原问题的弹性场可分成三部分;二部分由真实均匀本征应变所引起,另一部分由等效的非均匀本征应变所引起,后一部分则由虚拟的Somigliana位错场所产生。本文求得了等效非均匀本征应变和虚拟位错场的Burger矢量的解析表达式,进而确定的问题的弹性场。 相似文献
22.
本文将空间轴对称问题的Папковиц-Neuber通解用复变量广义解析函数表示,推导出用复变函数法求解空间轴对称问题的基本公式,并以此为工具求得了含球形空腔或刚性夹杂的中厚圆板在轴对称弯曲变形时的完全解. 相似文献
23.
The stress state of an elastic orthotropic medium with an arbitrarily oriented triaxial ellipsoidal inclusion is analyzed.
A solution is obtained using the triple Fourier transform and the Fourier-transformed Green’s function for an infinite anisotropic
medium. The high efficiency of the approach is demonstrated by solving the problem for a transversely isotropic material with
a spheroidal cavity for which the exact solution is known. A numerical analysis is conducted to study the stress distribution
over the surface of the inclusion with different orientations in the orthotropic space. It is revealed that in some cases
the orientation of the inclusion has a strong effect on the stress concentration
__________
Translated from Prikladnaya Mekhanika, Vol. 43, No. 4, pp. 55–61, April 2007. 相似文献
24.
In this paper we consider mathematical models describing dynamic viscoelastic contact problems with the Kelvin–Voigt constitutive law and subdifferential boundary conditions. We treat evolution hemivariational inequalities which are weak formulations of contact problems. We establish the existence of solutions to hemivariational inequalities with different types of non-monotone multivalued boundary relations. These results are consequences of an existence theorem for second order evolution inclusions. In a particular case we deliver sufficient conditions under which the solution to a hemivariational inequality is unique. Finally, applications to several unilateral and bilateral problems in contact mechanics are provided.*Research supported in part by the State Committee for Scientific Research of the Republic of Poland (KBN) under Grants no. 2 P03A 003 25 and 4 T07A 027 26. 相似文献
25.
Interaction between an edge dislocation and a circular inclusion with an inhomogeneously imperfect interface 总被引:2,自引:0,他引:2
This research presents an analytical study of the interaction problem of an edge dislocation with a circular inclusion with a circumferentially inhomogeneously imperfect interface. The interface, which is modeled as a spring (interphase) layer with vanishing thickness, is characterized by that in which there is a displacement jump across the interface in the same direction as the corresponding tractions, and the same degree of imperfection is realized in both the normal and tangential directions. Furthermore, the interface parameter is nonuniform along the interface. In order to arrive at an elementary form solution, we introduce a conformal mapping function. Then the stress field as well as the Peach–Koehler force acting on the edge dislocation can be obtained from the derived complex potentials. Calculations demonstrate that the nonuniform interface parameter has a significant influence on the stress field. 相似文献
26.
27.
I. Yu. Tsvelodub 《Journal of Applied Mechanics and Technical Physics》2006,47(6):899-904
An infinite elastic isotropic plate with an elliptical, physically nonlinear inclusion loaded at infinity by uniformly distributed
moments is considered. Surface loads are absent. The problem of the stress-strain state of the plate is solved in a closed
form. It is shown that, for reasonably general stress-strain relations for the inclusion, the bending-moment field (and the
corresponding curvatures) in the inclusion is homogeneous.
__________
Translated from Prikladnaya Mekhanika i Tekhnicheskaya Fizika, Vol. 47, No. 6, pp. 152–157, November–December, 2006. 相似文献
28.
Three kinds of photoresponsive copolymers with azobenzene side chains were synthesized by radical polymerization of N‐4‐phenylazophenylacrylamide (PAPA) with N‐isopropylacrylamide (NIPAM), N,N‐diethylacrylamide (DEAM) or N,N‐dimethylacrylamide (DMAM) respectively. Their structures were characterized by FT‐IR, 1H‐NMR and UV/Vis spectroscopy. Their reversible photoresponses were studied with or without α‐cyclodextrin (α‐CD), which showed that both the copolymers and their inclusion complexes with α‐CD underwent rapid photoisomerization. The lower critical solution temperature (LCST) of the copolymers and their inclusion complexes with α‐CD were investigated by cloud point measurement, which showed that the LCST of three kinds of copolymers increased largely after adding α‐CD. After UV irradiation on the solutions of copolymers and their inclusion complexes, the LCST of the copolymers increased slightly with the absence of α‐CD, while decreased largely with the presence of α‐CD. Furthermore, the LCST reverted to its originality after visible light irradiation. This change of LCST could be reversibly controlled by UV and visible light irradiation alternately. In particular, in the copolymer of PAPA and DMAM, the reversible water solubility of the inclusion complexes could be triggered by alternating UV and visible light irradiation. 相似文献
29.
In this study, two poly(azomethine ether)s were synthesized and they can form inclusion compounds (ICs) with β‐cyclodextrin (β‐CD). Fourier transform infrared (FTIR) spectroscopy, 1H nuclear magnetic resonance spectroscopy (1H‐NMR), thermogravimetric analysis (TGA), X‐ray diffraction (XRD) have been utilized to observe the formation of polymer‐CD‐ICs. The differentiation in their FTIR spectra may indicate the formation of the inclusion compounds between poly(azomethine ether)s and β‐CD. Compared the 1H‐NMR of polymer‐CD‐ICs with β‐CD, proton signals belonging to both β‐CD and poly(azomethine ether)s can be found in the spectrum. The chemical shift of the protons H‐3, H‐5 has changed after the formation of inclusion compounds, which is perhaps due to the interaction of these protons with polymers. TGA scans showed the much higher decomposition temperatures observed for two polymer‐CD‐ICs may imply that polymer chains included inside the β‐CD's cavity can greatly improve β‐CD's stabilities. The X‐ray diffraction patterns were confirmed to be the new crystal structures. 相似文献
30.
本文采用超声法制备了柚皮素(NAR)与β-环糊精(βCD)的包合物.粉末-X射线衍射(XRD)和红外吸收光谱(IR)测定均表明形成的包合物具有不同于主客体的新的结构性质.1H NMR与ROESY核磁共振(NMR)实验表明NAR以苯环端从βCD的宽口端进入,并形成稳定的超分子包合物.量子化学计算分析NAR/βCD包合物的形成过程表明,驱动力源于焓驱动与氢键弱相互作用力;能隙和结合能分析得到的最优包合模式与NMR研究结果一致;ONIOM分层计算验证了上述结果.分子对接模拟出的最优包合模式也与量子化学计算、NMR的分析结果吻合.本文获取了清晰的NAR/βCD包合物构型及其形成机理,为该超分子药物的定量构效关系研究提供了理论参考. 相似文献