M. Tazi¹, F. Erchiqui^1,*, F.Godard¹, H. Kaddami²

Journal of Renewable Materials, Vol.2, No.4, pp. 258-263, 2014, DOI:10.7569/JRM.2014.634120

Abstract This article evaluates the mechanical properties and biodegradability of wood-plastic composite materials made from sawdust and thermoplastic polymer (HDPE). For the preparation of the composites, sawdust in different proportions with Maleic Anhydride grafted Polyethylene (MAPE) as the coupling agent was used. The mechanical properties and biodegradability of the biocomposites were successively characterized. The results indicate that adding sawdust particles to a polymer matrix improves the mechanical strength and stiffness of composites. The tensile strength of a composite with 3% coupling agent was improved by 13%, 34% and 54% respectively when 20%, 30% and 40% wood… More >

Amar Boukerrou^*, Dalila Hammiche, Djidjelli Hocine, Hassina Aouat

Journal of Renewable Materials, Vol.2, No.4, pp. 249-257, 2014, DOI:10.7569/JRM.2014.634119

Abstract The lack of compatibility between cellulose fi bers and some polymers, such as thermoplastics, is due on one hand to the hydrophilic nature of the vegetable fi bers and on the other hand to the hydrophobic character of the matrix. This incompatibility induces bad dispersion of the fi bers and the formation of a heterogeneous material with mechanical properties which are not very satisfactory. The scope of this article is to describe the possibility of using Olive Husk Flour (OHF) as reinforcement in the elaboration of a composite material based on polyvinyl chloride (PVC). In More >

Vincenzo Gulizzi^1,2, Piervincenzo Rizzo^2,3, Alberto Milazzo⁴

Structural Durability & Health Monitoring, Vol.10, No.1, pp. 19-54, 2014, DOI:10.3970/sdhm.2014.010.019

Abstract The electromechanical impedance (EMI) method is one of the many nondestructive evaluation approaches proposed for the health monitoring of aerospace, civil, and mechanical structures. The method consists of attaching or embedding one or more wafer-type piezoelectric transducers (PZTs) to the system of interest, the host structure, and measuring certain electrical characteristics of the transducers. As these characteristics are also related to the impedance of the host structure, they can be used to infer the mechanical properties of the monitored structure. In the study presented in this paper, we utilize the EMI to monitor the quality… More >

Shasha Yang, Shengping Shen¹

CMC-Computers, Materials & Continua, Vol.40, No.3, pp. 219-239, 2014, DOI:10.3970/cmc.2014.040.219

Abstract As well known, gradient theories can describe size effects that are important in nano-scale problems. In this paper, we analyze the Eshelby-type anti-plane inclusion problem embedded in infinite dielectric body by considering both strain gradient and electric field gradient effects to account for the size effect and high-order electromechanical coupling effect. The size-dependent Eshelby and Eshelby-like tensor, strain, stress, electric field and electric displacement components are derived explicitly by means of Green's function method. Theoretical results indicate that strain and electric field are decoupled for anti-plane inclusion problem while stress field and electric displacement are More >

Y. Zhang¹, Y. F. Nie², Y. T. Wu¹

CMC-Computers, Materials & Continua, Vol.40, No.3, pp. 203-218, 2014, DOI:10.3970/cmc.2014.040.203

Abstract The present study aims to evaluate the mechanical properties of steel fiber reinforced concrete (SFRC) by the statistical second-order two-scale (SSOTS) method. At first, the representation for microstructure of SFRC is described by a concept of statistical screen. According to the microstructure representation, the SSOTS method is displayed in a concise way. This method is on the basis of asymptotic expansion homogenization and Monte Carlo method, and can calculate the local strain and stress field through the two-order displacement solution. As the classical homogenization method, the expression of homogenized elastic modulus is derived analytically. Then More >

R. Allena^*,†

Molecular & Cellular Biomechanics, Vol.11, No.3, pp. 185-208, 2014, DOI:10.3970/mcb.2014.011.185

Abstract Confined migration is a crucial phenomenon during embryogenesis, immune response and cancer. Here, a two-dimensional finite element model of a HeLa cell migrating across constricted–curved micro-channels is proposed. The cell is modelled as a continuum with embedded cytoplasm and nucleus, which are described by standard Maxwell viscoelastic models. The decomposition of the deformation gradient is employed to define the cyclic active strains of protrusion and contraction, which are synchronized with the adhesion forces between the cell and the substrate. The micro-channels are represented by two rigid walls and exert an additional viscous force on the… More >

Norizadeh Abbariki Tannaz^*,†, Shokrgozar Mohammad Ali^†,‡, Haghighipour Nooshin^*,§, Aghdami Nasser^¶, Mahdian Rezak^II, Amanzadeh Amir^*, Jazayeri Maryam^*,†

Molecular & Cellular Biomechanics, Vol.11, No.1, pp. 19-37, 2014, DOI:10.3970/mcb.2014.011.019

Abstract Background: Environmental factors affect stem cell differentiation. In addition to chemical factors, mechanical signals have been suggested to enhance myogenic differentiation of stem cells. Therefore, this study was undertaken to illustrate and compare the effect of chemical and mechanical stimuli on Myogenin (MyoG) and Myosin heavy chani 2 (Myh2) expression of mouse bone marrowderived mesenchymal stem cells (BMSCs) and embryonic stem cells (ESCs). Methods: After isolation and expansion of BMSCs and generation of embryoid bodies and spontaneous differentiation of ESCs, cells were examined in 4 groups: (1) control group: untreated cells; (2) chemical group: cells… More >

M. Toujani¹, R. Djebali², L. Hassini¹, S. Azzouz¹, A. Belghith¹

CMES-Computer Modeling in Engineering & Sciences, Vol.98, No.5, pp. 469-485, 2014, DOI:10.3970/cmes.2014.098.469

Abstract In the present work we aim to simulate unsteady two-dimensional evolution of the moisture content, temperature and mechanical stress in a parallelepiped apple sample during convective drying. The model is based on the heat and mass transfer equations and the mechanical equilibrium equation under the assumptions of plane deformation, viscoelasticity and isotropic hydric shrinkage. The Finite Elements COMSOL Multiphysics solver is used to solve the developed model. The hydro-thermal model was validated on experimental data drawn in our laboratory for moisture and temperature internal profiles of the product. Excellent agreement has been obtained between numerical More >

V.B.Shim ¹, K. Mithraratne ¹

CMES-Computer Modeling in Engineering & Sciences, Vol.98, No.3, pp. 279-294, 2014, DOI:10.32604/cmes.2014.098.279

Abstract The activation of NF-kB is an important precursor in developing melanoma. However the role of mechanical stimulation in the NF-kB activation has not been studied. We used a multiscale computational modeling approach to investigate the role of mechanical stimulation and the skin tissue internal structures in the activation of NF-kB. Our model is made up of three levels – 1) the macro level where a FE model of the Zygomaticus major muscle was developed; 2) the meso level where a micro FE model of the skin block using a sample from human cadaver was developed;… More >

Zhengzheng Cao¹, Yuejin Zhou^1,2, Ping Xu¹, Jiawei Li¹

CMES-Computer Modeling in Engineering & Sciences, Vol.101, No.5, pp. 351-364, 2014, DOI:10.3970/cmes.2014.101.351

Abstract In accordance with the influence of underground mining on the deformation and failure of a shallow-buried gas pipeline, the pipe-soil interaction during mining is classified into two stages, namely coordinated deformation stage and partial hanging stage. According to the mechanical characteristics of the buried pipeline in each stage, the models of a) a beam on an elastic foundation, b) an elastic beam under uniform load, and c) a vertical and horizontal bending beam are introduced in a mining subsidence zone to mechanically analyze, respectively a) the pipeline in non-mining subsidence zone, b) the pipeline at… More >