Toufik Sahabi^1,*, Smain Balaska²

FDMP-Fluid Dynamics & Materials Processing, Vol.19, No.4, pp. 977-990, 2023, DOI:10.32604/fdmp.2022.022059

Abstract The heat transfer equation is used to determine the heat flow by conduction through a composite material along the real axis. An analytical dimensionless analysis is implemented in the framework of a separation of variables method (SVM). This approach leads to an Eigenvalues problem that is solved by the Newton’s method. Two types of dynamics are found: An unsteady condition (in the form of jumps or drops in temperatures depending on the considered case), and a permanent equilibrium (tending to the ambient temperature). The validity and effectiveness of the proposed approach for any number of adjacent layers is also discussed.… More > Graphic Abstract

Yun Zhang¹, Lingfeng Zhang², Zhiwei Shan³, Lu Wang^1,*, Weiqing Liu¹

Journal of Renewable Materials, Vol.7, No.11, pp. 1093-1108, 2019, DOI:10.32604/jrm.2019.07335

Abstract It is well known that the use of woods as construction materials can embody carbon content of structural members, which can enhance the urban sustainability. However, due to the combustibility of wood, its current application is restricted. To broaden the application of wood, its thermal responses exposed to fire (high temperature) is investigated in this study. Firstly, the wood kinetic parameters are determined by coats-redfern method using thermal gravimetric (TGA) data. Secondly, the density and thermal conductivity are obtained from parallel and series models. Thirdly, the specific heat capacity formula is presented considering latent and decomposition heat, which can be… More >

Changqing Fu^1,2, Jiahui Wang^1,2, Lie Chen^1,2, Liang Shen^1,2,*

Journal of Renewable Materials, Vol.7, No.8, pp. 795-805, 2019, DOI:10.32604/jrm.2019.07503

Abstract In this paper, a fully bio-based vinyl oligomer with high functionalities was successfully prepared from rapeseed oil by three modification steps: epoxidation of rapeseed oil, solvent-free and catalyst-free ring opening by 10-undecylenic acid followed by esterification with 10-undecenoyl chloride. Then, the renewable polymers were prepared by photo-polymerization of these modified vegetable oils with typical thiol monomers: pentaerythritol tetrakis (3-mercaptopropionate), pentaerythritol tris (3-mercaptopropionate) and 1,2-ethanedithiol. The synthesis of the vinyl oligomer was monitored by nuclear magnetic resonance and Fourier-transform infrared spectroscopy. The average number of the carbon-carbon double bonds of the resulting vinyl oligomer is high to be 7.2. The kinetic… More >