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A novel trinuclear iron complex was synthesized in ethanol solution, [Fe 3 O(ClC 6 H 4 CO 2 ) 6 (H 2 O) 2.5 (C 2 H 5 OH) 0.5 ]ClO 4 ·0.5H 2 O. The title complex crystallizes in the tetragonal system, space group $P_{4_1}$

DMF (dimethylformamide) reacts with Gd(NO3)36H2O and K3Mn(CN)6 to afford a novel cyano-bridged complex [Gd(DMF)4(H2O)2Mn(CN)6] · H2O] n . The crystal structure of the complex (abbreviated as GdMn) has shown that it has a novel one-dimensional chain structure. The complex crystallizes in space group P21/c with a = 13.004(2), b = 12.762(2), c = 19.160(4) A, β = 109.51(3)°, V = 2997.2(9) A, Dx = 1.584 Mgm−3, Z = 4. Variable temperature (1.5–300K) magnetism shows there exists weak antiferromagnetic interaction between Gd and Mn atoms across the cyano bridge.

In the Fourier spectral analyzer, the Fourier spectra or the Fraunhofer diffraction pattern of an image is formed on the back focal plane when a laser beam is directed on the image lying on the front focal plane. If the image is deformed, its Forier spectra are also subjected to change. Therefore the change of the Fourier spectra provides a particular beautiful insight into the deformation of that image. Through proposing the corresponding relationship between the image and its spectra, and analyzing the change of Fourier spectra, the deformation of the image can be obtained. Based on Fourier optical theory and S-R decomposition theorem of finite deformation, in this paper, a state of the art deformation measurement technique is presented by using laser spectral analysis. The theoretical foundation of this new technique related to mathematics and optics, experimental principle and the technique of automatic recognizing and processing of the deformed spectral image is discussed. The paper is as a special commemoration and memorial to the death anniversary of Professor Chen Zhida (1927–1998), who initially proposed the above academic idea in early 80s.

In this paper, based on the finite deformation S-R decomposition theorem, the definition of the body moment is renewed as the sum of its internal and external. The expression of the increment rate of the deformation energy is derived and the physical meaning is clarified. The power variational principle and the complementary power variational principle for finite deformation mechanics are supplemented and perfected.

In this paper, the effective stress for multi-porosity elasticity model is presented by means of stress analysis for double porosity media elements. It is found that the effective stress law is not unique, it depends on the hypothesis of constitutive equations for multi-porosity media. Diversified effective stress laws for multi-porosity are developed.

Localized deformation and instability is the focal point of research in mechanics. The most typical problem is the plastic analysis of cylindrical bar necking and shear band under uniaxial tension. Traditional elasto-plastic mechanics of infinitesimal deformation can not solve this problem successfully. In this paper, on the basis of S(strain)-R(rotation) decomposition theorem, the authors obtain the local strain distribution and progressive state of axial symmetric finite deformation of cylindrical bar under uniaxial tension adopting nonlinear gauge approximate method and computer modelling technique.

The development of modern mechanics in recent years has made many important progresses in the concepts and methods for nonlinear large deformation mechanics ([1], [2], [3]etc.). The present paper is aimed to show how the natural co-moving system method and Stokes-Chen's decomposition theorem can be effectively applied asymptotically to solving problems of finite deformation elasto-plasticity by inverse asymptotic method for engineering design purpose. Rigid punch problem is examplified in the paper.

For a physically possible deformation field of a continuum, the deformation gradient function F can be decomposed into direct sum of a symmetric tensor S and an orthogonal tensor R, which is called S-R decomposition theorem. In this paper, the S-R decomposition unique existence theorem is proved, by employing matrix and tensor method. Also, a brief proof of its objectivity is given.

Based on the nonlinear geometry field theory of continuum mechanics, this paper analyses the stress field due to a screw dislocation in an infinite medium. The results re veal the high-order effect of the stress field. When this effect is small, the result can be reduced to one of the classical linear clasticity. The body couple field of the screw dislocation is also investigated in this paper. The analytical expression of the body couple due to a screw dislocation is obtained with small rotation deformation. As the application of theoretical results, the stress and the body couple at the interface of the crystals are calculated when the screw dislocation is near the interface.

In this paper, a nonlinear theory of nonlocal asymmetric, elastic solids is developed on the basis of basic theories of nonlocal continuum field theory and nonlinear continuum mechanics. It perfects and expands the nonlocal elastic field theory developed by Eringen and others. The linear theory of nonlocal asymmetric elasticity developed in [1] expands to the finite deformation. We show that there is the nonlocal body moment in the nonlocal elastic solids. The nonlocal body moment causes the stress asymmetric and itself is caused by the covalent bond formed by the reaction between atoms. The theory developed in this paper is applied to explain reasonably that curves of dispersion relation of one-dimensional plane longitudinal waves are not similar with those of transverse waves.

The energy-localized CNDO/2 molecular orbitais have been calculated for the clusters containing molybdenum, > {Mo 3 S 4 2 Mo} 8+ and > Mo 3 S 4 ]CuI > 4+ , versus the prototype arene-metal sandwich (C 6 H 6 ) 2 Cr and half-sandwich complexes C 6 H 6 Cr(CO) 3 . The bonding characteristics of these compounds are described from a localization bonding viewpoint. There are two typical M-arene and M-[Mo 3 S 4 ] bondings. One is formed by electron donation from the three-center two-electron π-bonds in the arene or [Mo 3 S 4 ] 4+ ligands into the vacant hybrid orbitais of the “stranger” metal atom. In the other M-arene or M-[Mo 3 S 4 ] bond there is very little donation by the lone electron pair occupying the d AOs of the “stranger” metal atom to the arene or [Mo 3 S 4 ] 4+ ligands. The analogy of the ligand [Mo 3 S 4 ] 4+ in the clusters studied with the ligand benzene is also briefly discussed.

In this paper we deal with the second-order effect of an elastic circular shaft during torsion. The analysis is based on the method of co-moving coordinates and the strain-rotation decomposition theorem[1] in continuum mechanics. By using asymptotic expansion methods, we comfirm that the effect of axial elongation and distortion of plane cross-section exists in an elastic circular shaft during large torsion and give the expressions of the axial force and the torque.

Living system is a non-equilibrium open system having the function of self-organization and self-control. The study of energy principle of living system involves two principal parts: mechanics and thermodynamics. The classical infinitesimal deformation theory and thermodynamics of equilibrium state are not sufficient to explain the complex motion of living system. We aim in this paper to describe the mechanical energy principle of macroscopic motion of living body based on large deformation non-symmetry stress field theory. The principle of irreversible thermodynamics applied to living system will be left in another paper[9].

Based on the variational equation derived in ref. [1], a nonlinear incremental F.E. equation is formulated for unilateral contact elastic and plastic large deformation problems. A new technique-co-moving coordinate finite element method is introduced, and a practical mathematical model for large deformation contact problem is described. To show the effectiveness of the method, problems of contact large deformation of cantilever beam, circular plate, as well as metal ring are computed. Compared with experiments, the results show good agreements.