Galussi AA¹, JA Argüello², MM Cerana², M Maximino³, ME Moya¹

Phyton-International Journal of Experimental Botany, Vol.84, No.1, pp. 163-175, 2015, DOI:10.32604/phyton.2015.84.163

Abstract Seeds of alfalfa (Medicago sativa L.) can exhibit seedcoat imposed dormancy, which produces hard seeds within a seed lot. These seeds do not germinate because they do not imbibe water due to a barrier to water entry in the seed coat. The aim of this work was to analyze the anatomical and chemical characteristics of the testa of alfalfa seeds with respect to water permeability levels. The anatomy of seeds of the cv. Baralfa 85 was studied and structural substances, polyphenols, tannins and cutin present in the testa of seeds of different water permeability levels were determined. The anatomical characteristics… More >

Odin RAMÍREZ-FERNÁNDEZ^1,2,3,*, Ludovika CACOPARDO¹, Benjamín LEON-MANCILLA², Joana COSTA¹

BIOCELL, Vol.43, No.1, pp. 29-36, 2019, DOI:10.32604/biocell.2019.04790

Abstract We present a bioreactor system which combines a semi permeable membrane that simulates the osmotic nutrients interchange in the small intestine circulation and rhythmic peristaltic movement. This custom-designed presents a semipermeable membrane bioreactor, with peristaltic flow and compression variation that allows adjustment of luminal flow rate. In addition, this system is also capable of achieving the drug distribution in the small intestine model from the apical compartment to the basal compartment by the semipermeable channel. This dynamic bioreactor can mimic the human small intestine with increased accuracy to overcome many of the limitations and accuracy with the previously described in… More >

Yi Xue^1,2,*, Faning Dang², Rongjian Li², Fei Liu³

CMES-Computer Modeling in Engineering & Sciences, Vol.115, No.3, pp. 345-358, 2018, DOI: 10.3970/cmes.2018.08052

Abstract Adsorption deformation significantly affects the seepage characteristics of coal. However, effect of sorption time on coal permeability and gas pressure has not been investigated systematically. In this study, the sorption experiment of coal samples is conducted to elaborate the importance of sorption equilibration time. Then a coupled coal deformation and gas flow model is established considering the sorption characteristic and permeability evolution. This coupled model is implemented through finite element method to analyze the effect of sorption time on coal permeability and gas pressure. The simulation results reveal that the gas pressure of the coal will change with the adsorption… More >

Ragab E. Abou-Zeid^1*, Mohamed A. Diab¹, Salah A. A. Mohamed², Ahmed Salama¹, Hind Abdullah Aljohani³, Kamel Rizq Shoueir⁴

Journal of Renewable Materials, Vol.6, No.4, pp. 394-401, 2018, DOI:10.7569/JRM.2017.634156

Abstract The current article addresses a new strategy for the preparation of polylactic acid/cellulose nanocrystal (PLA/CNCs) nanobiocomposite films with improved structural morphology, mechanical and barrier properties for food packaging applications. The addition of hexadecyltrimethylammonium bromide (CTAB) and sodium lauryl sulfate (SLS) as cationic and anionic surfactants respectively, was found to play a crucial role in preventing re-aggregation of the CNCs during drying and improving the dispersion of CNCs in the PLA. The coated paper was characterized using mechanical tests, water vapor permeability (WVP), X-ray diffraction (XRD), scanning electron microscopy (SEM) and air permeability. The results showed that the paper coated with… More >

Itxaso Algar¹, Clara Garcia-Astrain¹, Alba Gonzalez², Loli Martin³, Nagore Gabilondo¹, Aloña Retegi^1*, Arantxa Eceiza^1*

Journal of Renewable Materials, Vol.4, No.1, pp. 57-65, 2016, DOI:10.7569/JRM.2015.634124

Abstract Bacterial cellulose/montmorillonite (BCMMT) hybrid bionanocomposite membranes were prepared by in-situ assembling or one-step biosynthesis process. The presence of MMT in BC membranes was confi rmed by thermogravimetric analysis and quantifi ed by mass spectrometry, resulting in bionanocomposites with MMT contents between 7–13 wt%. The incorporation of MMT during BC biosynthesis modifi ed BC morphology and led to lower porosity, even though higher water holding capacity was achieved. Bionanocomposites showed improved thermal stability and water vapor and oxygen gas barrier properties up to 70 and 80% with respect to neat BC membranes. This improvement was related to the tortuous path of… More >

Jing Zhang^1,2,3, Xiuqing Qian^1,2, Haixia Zhang^1,2, Zhicheng Liu^1,2,*

CMES-Computer Modeling in Engineering & Sciences, Vol.116, No.2, pp. 301-314, 2018, DOI: 10.31614/cmes.2018.04239

Abstract Elevated intraocular pressure appears to have a broader impact on increased resistance to aqueous humor outflow through the conventional aqueous outflow system (AOS). However, there is still no consensus about exact location of the increased outflow resistance of aqueous humor, and the mechanism is not perfect. In addition, it is difficult to accurately obtain hydrodynamic parameters of aqueous humor within the trabecular meshwork outflow pathways based on the current technology. In this paper, a two-way fluid-structure interaction simulation was performed to study the pressure difference and velocity in the superficial trabecular meshwork, juxtacanalicular meshwork (JCM) and Schlemm’s canal in response… More >

Yi Xue^1,2,3

CMES-Computer Modeling in Engineering & Sciences, Vol.113, No.4, pp. 429-441, 2017, DOI:10.3970/cmes.2017.113.429

Abstract The lack of research on the effect of diffusion on methane extraction leads to low methane concentration and low utilization. The Comsol Multiphysics software is used to solve the numerical gas and solid coupled model which considers the diffusion of coal matrix, fracture seepage, permeability evolution and coal deformation. The simulation results reveal the effect of diffusion process on methane migration. The gas diffusion rate is relatively high in the initial stage. With the increase in time, the difference between coal fractures and coal matrix blocks becomes lower and the gas diffusion rate decreases gradually. The gas seepage rate decreases… More >

M.Galli , M.L.Oyen¹

CMES-Computer Modeling in Engineering & Sciences, Vol.48, No.3, pp. 241-270, 2009, DOI:10.3970/cmes.2009.048.241

Abstract A novel approach is presented for the identification of constitutive parameters of linear poroelastic materials from indentation tests. Load-controlled spherical indentation with a ramp-hold creep profile is considered. The identification approach is based on the normalization of the time-displacement indentation response, in analogy to the well-known one-dimensional consolidation problem. The identification algorithm consists of two nested optimization routines, one in the time-displacement domain and the other in a normalized domain. The procedure is validated by identifying poroelastic parameters from the displacement-time outputs of finite element simulations; the new identification scheme proves both quantitatively reliable and fast. The procedure is also… More >

Z. Zhong¹, Y. Dai^1,2, C. C. Mei³, P. Tong^1,4

CMES-Computer Modeling in Engineering & Sciences, Vol.3, No.1, pp. 77-86, 2002, DOI:10.3970/cmes.2002.003.077

Abstract In this paper we reexamine the sheet-flow model proposed by Fung and Sobin (1969) for blood flow in capillaries in the pulmonary alveoli from micromechanical point of view. The pulmonary alveolar capillary is assumed to be two parallel membranes connected by periodic tissue posts. Blood is spread out into the very thin layer or sheet between the two membranes. The pulmonary alveolar sheet thus has a microstructure of hexagonal cells. A two-scale theory of homogenization is used to establish the canonical equations for the unit cell. The microscale solution is obtained by means of finite element method and the macroscopic… More >

A. Khechiba¹, Y. Benakcha¹, A. Ghezal¹, P. Spetiri²

FDMP-Fluid Dynamics & Materials Processing, Vol.14, No.2, pp. 137-154, 2018, DOI: 10.3970/fdmp.2018.04054

Abstract This work investigates the dynamic behavior of a pulsatile flow electrically conducting through porous medium in a cylindrical conduit under the influence of a magnetic field. The imposed magnetic field is assumed to be uniform and constant. An exact solution of the equations governing magneto hydro-dynamics (MHD) flow in a conduit has been obtained in the form of Bessel functions. The analytical study has been used to establish an expression between the Hartmann number, Darcy number and the stress coefficient. The numerical method is based on an implicit finite difference time marching scheme using the Thomas algorithm and Gauss Seidel… More >