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101.
We give a new proof of Kolodner's result that longitudinal waves can propagate in at least three directions in a hyperelastic
anisotropic medium. We give examples of an orthotropic hyperelastic tensor with exactly three such directions, of a monoclinic
elastic (but not hyperelastic) tensor with only one, and of a monoclinic elastic (elliptic, but not uniformly elliptic) tensor
with no direction for longitudinal waves.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
102.
Based on the Floquet theory on ordinary differential equations with periodically variable coefficients and the bifurcation
approach to nonlinear equations, a numerical approach to determining the stability region of control parameters is established
for a dynamic control system composed of a moving body levitated magnetically over flexible guideways. The system is nonlinearly
coupled among the elastic deformation of guideways, disturbance the levitation position of the body and electromagnetic control
forces. The numerical simulation is given for the system in the case in which the control parameters are taken within and
out of the stability region respectively. Results show that this approach is reliable.
This project is supported by NSFC(No. 19725207), the Pre-research Project of the Committee of Science and Technology for Defence
of China and the Science Foundation of Education Ministry of China for Ph. D. Programmes. 相似文献
103.
104.
105.
HUANG Jianguo SHI Zhongci & XU Yifeng Department of Mathematics Shanghai Jiaotong University Shanghai China Division of Computational Science E-lnstitute of Shanghai Universities Shanghai Normal University China Institute of Computational Mathematics Academy of Mathematics System Sciences Chinese Academy of Sciences Beijing China 《中国科学A辑(英文版)》2005,48(7):986-1007
The aim of this paper is to study the static problem about a general elastic multi-structure composed of an arbitrary number of elastic bodies, plates and rods. The mathematical model is derived by the variational principle and the principle of virtual work in a vector way. The unique solvability of the resulting problem is proved by the Lax-Milgram lemma after the presentation of a generalized Korn's inequality on general elastic multi-structures. The equilibrium equations are obtained rigorously by only assuming some reasonable regularity of the solution. An important identity is also given which is essential in the finite element analysis for the problem. 相似文献
106.
Analysis results for the elastic properties of a composite with a small amount of coplanarly arranged platelike filler particles
are presented. The geometrical form of the particles is described by an oblate ellipsoid of revolution. The calculations are
performed by formulas obtained by using the Eshelby approach for media with a low concentration of inclusions. The effect
of anisometry of the ellipsoidal particles and of the ratio between the elastic moduli of the filler and matrix on the effective
elastic constants of the composite is discussed. Calculation results are compared with experimental data for the elastic moduli
of a nanocomposite containing completely exfoliated particles of an unmodified montmorillonite.
__________
Translated from Mekhanika Kompozitnykh Materialov, Vol. 44, No. 4, pp. 493–504, July–August, 2008. 相似文献
107.
LU Juan ZHOU Li-Huan MA Wei-Xing HE Xiao-Rong 《理论物理通讯》2008,49(1):207-211
Based on the quark-gluon structure of nucleon and the existence of Odderon in nucleon via gluon selfinteraction, the elastic scattering of pp at high energies is studied. Our theoretical predictions reproduce experimental data perfectly. The contributions from individual terms of quark-quark, gluon-gluon interactions, quark-gluon interference and the Odderon terms to total cross section are analyzed. In addition to the leading quark-quark contribution, the Odderon contribution is quite important. In particular, the Odderon plays an essential role in fitting to data. Therefore, We may claim that the high energy pp and pp elastic scattering may be good processes to search for the Odderon, the three Reggeized gluon bound states. 相似文献
108.
F. Bavaud 《Journal of statistical physics》1986,45(1-2):171-181
New expressions for the elastic moduli of a classical system are derived. They involve only the two-point correlation function and the derivative of the onepoint correlation function, both only on the boundary of the system. These expressions, valid for any interaction derivable from a potential, are proved from a mechanical point of view by generalizing the virial theorem of Clausius, and from a statistical point of view by a direct method that constitutes an alternative to Green's dilatation method. 相似文献
109.
Joaquin Valencia Juan Baselga Ines F. Pierola 《Journal of Polymer Science.Polymer Physics》2009,47(11):1078-1087
Several hydrogels of N‐vinylimidazole and sodium styrenesulfonate have been prepared by radical cross‐linking copolymerization in aqueous solution, using N,N′‐methylene‐bisacrylamide as crosslinker. Depending on composition, these hydrogels were neutral, amphoteric, cationic or anionic. Compression‐strain measurements were performed on samples as‐synthesized and swollen in deionized water or in acid aqueous solutions, with and without salt. It was thus found that the cross‐linking densities determined by compression measurements on as‐synthesized samples are in good accordance with those calculated by means of the model of polymer networks with pendant vinyl groups. A non‐Gaussian parameter (β) was introduced to explain that the elastic moduli (G) of samples swollen at equilibrium are larger than predicted by the Gaussian model. The β values of the neutral or ionized systems increase with swelling and fall into a single curve, which denotes a common behavior. Swelling has two opposite effects on G; on the one hand G decreases because the polymer volume fraction diminish and the system shifts from the affine limit to the phantom one; on the other, β increases and contributes to increasing G. The balance of those two opposite effects determines the variation of G with swelling. The possible contribution of ionic crosslinks to νe for the polyampholyte and for the polycation wearing divalent counteranions was discussed. A peculiar system is poly(sodium styrenesulfonate), whose cross‐linking density is much lower than expected. © 2009 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 47: 1078–1087, 2009 相似文献
110.