Dongze Yan¹, Jianxiang Wang², Lihua Shao^1,*

The International Conference on Computational & Experimental Engineering and Sciences, Vol.27, No.1, pp. 1-2, 2023, DOI:10.32604/icces.2023.09357

Abstract Non-uniform strains produce a localized break in the microscopic inverse symmetry of materials, which leads to the electromechanical coupling phenomenon known as flexoelectricity in all dielectric materials. However, the size-dependent flexoelectric effect typically only manifests at small scales. Creating a considerable flexoelectric output at the macroscopic scale remains a bottleneck. Micro- and nano-porous materials own a significant number of randomly distributed microscopic pores and ligamentous structures, which can deform non-uniformly under arbitrary forms of macroscopic loading. Moreover, since the small size effect of flexoelectricity, the entire flexoelectricity of the micro- and nano-porous materials will be much more significant than that… More >

Isamu Riku^1,*, Koji Mimura¹

The International Conference on Computational & Experimental Engineering and Sciences, Vol.26, No.3, pp. 1-1, 2023, DOI:10.32604/icces.2023.09070

Abstract It is well known that the mechanical resistance of soft materials such as rubber and elastomer can be improved by cross-linkages or fillers, which will lead to a construction of entangled structure of polymer chains’ network. However, the correlation between the amount of cross-linkages or fillers with the toughness strength of the resultant material has not been clarified. Therefore, in this study, we at first construct a computational model for the resultant material with molecular dynamics method. Then, a series of simulations are performed for the resultant materials with different amount of cross-linkages or fillers under high speed loading condition.… More >

Ola Ragb¹, Mokhtar Mohamed², Mohamed S. Matbuly¹, Omer Civalek^3,*

CMES-Computer Modeling in Engineering & Sciences, Vol.137, No.3, pp. 2193-2217, 2023, DOI:10.32604/cmes.2023.028992

Abstract Four numerical schemes are introduced for the analysis of photocurrent transients in organic photovoltaic devices. The mathematical model for organic polymer solar cells contains a nonlinear diffusion–reaction partial differential equation system with electrostatic convection attached to a kinetic ordinary differential equation. To solve the problem, Polynomial-based differential quadrature, Sinc, and Discrete singular convolution are combined with block marching techniques. These schemes are employed to reduce the problem to a nonlinear algebraic system. The iterative quadrature technique is used to solve the reduced problem. The obtained results agreed with the previous exact one and the finite element method. Further, the effects… More > Graphic Abstract

Yuhui Huang¹, Zhiyuan Yin^1,2, Ming Liu¹, Meng Li¹, Yingfeng Zuo¹, Yan Qing¹, Yiqiang Wu^1,*

Journal of Renewable Materials, Vol.11, No.9, pp. 3417-3431, 2023, DOI:10.32604/jrm.2023.028511

Abstract The poor bonding performance between aqueous adhesives represented by melamine-urea formaldehyde (MUF) resins and reed straw hinders their applications in the field of non-wood-based panels. Multi-hydroxyl polymers are highly reactive and are often used as crosslinkers. This study fabricated a resin with a strengthened cross-linked structure by combining a multi-hydroxyl polymer and MUF resin prepolymer. The reed particleboard was prepared by using this resin as an adhesive and reed stalk as the matrix. The results show that neighboring molecules combined to form C–O–C bonds that strengthened the cross-linked structure of the resin. In addition, the viscosity of the resin was… More >

Harpreet Kaur Aasi, Vivek Kumar Gaba, Anil Kumar Tiwari, Shubhankar Bhowmick^*

Frontiers in Heat and Mass Transfer, Vol.8, pp. 1-6, 2017, DOI:10.5098/hmt.8.15

Abstract Due to low density and low coefficient of thermal expansion, orthotropic materials, namely, the polymer matrix composites are finding their way in many of the engineering application. The present study investigates the performance of the orthotropic annular fin. The thermal conductivity along radial and axial direction is governed by the thermal conductivity ratio (K), which is an important parameter for orthotropic annular fin. The work then numerically examines in two dimensions, the thermal performance of the annular fin at different thermal conductivity ratio (K) for the rectangular profile using the finite difference method. Different convective heat transfer coefficient are considered… More >

A. Subba Rao^a,* , V. Ramachandra Prasad^a , P. Rajendra^a , M. Sasikala^a , O. Anwar Beg^b

Frontiers in Heat and Mass Transfer, Vol.9, pp. 1-9, 2017, DOI:10.5098/hmt.9.2

Abstract In this article, we investigate the nonlinear steady state boundary layer flow and heat transfer of an incompressible Jeffery non-Newtonian fluid from a permeable horizontal isothermal cylinder. The transformed conservation equations are solved numerically subject to physically appropriate boundary conditions using a versatile, implicit, finite-difference technique. The numerical code is validated with previous studies. The influence of a number of emerging non-dimensional parameters, namely with Deborah number (De), surface suction parameter (S), Prandtl number (Pr), ratio of relaxation to retardation times (λ) and dimensionless tangential coordinate (ξ) on velocity and temperature evolution in the boundary layer regime are examined in… More >

Xiaoyan Liu^1,2, Zhao Qin^1,2,*, Yuxiang Ma^1,2, Huamin Liu^1,2,*, Xuede Wang^1,2

Journal of Renewable Materials, Vol.11, No.8, pp. 3203-3225, 2023, DOI:10.32604/jrm.2023.027613

Abstract Packaging is a food preservation technology widely used in the world. Naturally-sourced, biodegradable polymers are becoming increasingly popular in the food packaging sector. Packaging films prepared using cellulose as raw material would contribute to resource sustainability, but the difficulty of cellulose solubilization limits their further development. In view of this, a series of novel solvent systems (LiCl/DMAc, ILs, TBAH/DMSO, NMMO, alkali/urea solutions, metal-complex solutions) were used to prepare high-strength and high-performance cellulose-based films; their characteristics and the mechanisms involved were investigated. Composite films prepared by blending cellulose with various polymers (synthetic polymers, natural polymers, proteins and enzymes, metal particles, and… More > Graphic Abstract

Yue Yu^*

FDMP-Fluid Dynamics & Materials Processing, Vol.19, No.10, pp. 2681-2694, 2023, DOI:10.32604/fdmp.2023.028250

Abstract A triethylenetetramine epoxy mixture was synthesized through the reaction of a low-molecular-weight liquid epoxy resin with triethylenetetramine (TETA). Then triethyltetramine (TETA) was injected dropwise into a propylene glycol methyl ether (PM) solution for chain extension reaction. A hydrophilic and flexible polyether segment was introduced into the hardener molecule. The effects of TETA/DGEPG, reaction temperature and reaction time on the epoxy conversion of polyethylene glycol diglycidyl ether (DGEPG) were studied. In addition, several alternate strategies to add epoxy resin to the high-speed dispersion machine and synthesize MEA DGEBA adduct (without catalyst and with bisphenol A diglycidyl ether epoxy resin) were compared.… More >

Amer A. Abdulrahman¹, Bashar J. Kadhim¹, Zainab Y. Shnain¹, Hassan Sh. Majidi², Asawer A. Alwaiti^1,*, Farooq Al-Sheikh¹, Adnan A. AbdulRazak¹, Mohammed Shorbaz¹, Mazin J. Shibeeb³

FDMP-Fluid Dynamics & Materials Processing, Vol.19, No.10, pp. 2579-2595, 2023, DOI:10.32604/fdmp.2023.027454

Abstract The well-known frictional effect related to liquid-liquid two-phase flow in pipelines can be reduced using drag-reducing additives. In this study, such an effect has been investigated experimentally using a mixture of oil and water. Moreover, numerical simulations have been carried out using the COMSOL simulation software. The measurements were taken in a horizontal pipe with the length and diameter equal to 3 and 0.125 m, respectively. Moreover, Polyethylene oxide with 150 ppm was exploited to reduce the drag effect while considering different water-to-oil fractions (0.3, 0.4, 0.5, and 0.7) and a constant total flow velocity of 2.3 m/s. As made… More >

A.D.S.M.R. Pascoal^a , P.M. da Silva^b,c, M.N.C. Coelho Pinheiro^a,d,*

Frontiers in Heat and Mass Transfer, Vol.12, pp. 1-7, 2019, DOI:10.5098/hmt.12.29

Abstract Efforts have been made to obtain new drug formulations in ophthalmologic applications to replace eye drops that are inefficient. Soft contact lenses have been using as an ophthalmic drug delivery device. Several hydrogels were used to prepare solid matrices with the drug impregnated. Assuming drug diffusion within polymeric devices as the dominant mechanism in the mass transfer process, simple models were developed to describe drug release from an ocular delivery device. The timolol maleate (medicine for glaucoma treatment) dissolution profile in the release medium for methacrylate hydrogels based contact lenses were obtained experimentally and compared with predictions considering one-dimensional and… More >