Houda Saad^1,2,*, Antonio Pizzi^3,4, Bertrand Charrier², Naceur Ayed¹, Karsten Rode⁵, Fatima Charrier - El Bouhtoury²

Journal of Renewable Materials, Vol.3, No.1, pp. 34-43, 2015, DOI:10.7569/JRM.2014.634130

Abstract The possible use of Tunisian pomegranate tannins in wood adhesive formulation was studied for the fi rst time. Colorimetric tests, Fourier transformed infrared spectroscopy (FTIR), nuclear magnetic resonance (NMR) and matrix-assisted laser desorption/ionization time-of-fl ight (MALDI-TOF) mass spectrometry were used to examine pomegranate tannins. Analysis showed that pomegranate peels are rich in hydrolyzable tannins. The Stiasny number tests showed the low reactivity of pomegranate tannin extract to formaldehyde and thus the diffi culty of using it in wood adhesive formulation. Thermomechanical analysis (TMA) and strength analysis of pomegranate tannin/hexamine-based resin showed weak bonding properties. More >

Pronob Gogoi, Dhaneswar Das, Shyamalima Sharma, Swapan K. Dolui^*

Journal of Renewable Materials, Vol.3, No.2, pp. 151-159, 2015, DOI:10.7569/JRM.2014.634129

Abstract Alkyd resins based on Jatropha curcas oil with different molar ratios of phthalic anhydride (PA) and maleic anhydride (MA) were prepared by alcoholysis followed by polyesterifi cation reaction. The progress of the reaction was traced by the determination of acid value at regular time intervals. From the kinetic study the extent of the reaction was found in the range of 52.4–61.2%. The prepared resins were blended with a commercially available fast-curing epoxy resin in order to improve the properties like curing time, chemical resistance, tensile strength, and thermal stability. The morphology study of the blends More >

D.N. Dorr, S.D. Frazier, K.M. Hess, L.S. Traeger, W.V. Srubar III^*

Journal of Renewable Materials, Vol.3, No.3, pp. 195-204, 2015, DOI:10.7569/JRM.2015.634108

Abstract A study of the potential for gelatin-based derivatives to serve as biorenewable, biodegradable adhesives for wood and engineered wood products is presented in this article. The effect of gelatin-to-water weight percent on the mechanical, specifically ultimate breaking (bond) strength, and thermal properties was investigated using tensile testing and differential scanning calorimetry, respectively. The breaking strengths of the gelatin-based adhesives were characterized and compared to four commercially available wood adhesives. The effect of 1–5% tannin addition on the mechanical, thermal, and moisture absorption behavior of the gelatin-based adhesives was also investigated. Results show that the gelatin-based More >

William Eberts, Matthew T. Siniawski^*, Timothy Burdiak, Nick Polito

Journal of Renewable Materials, Vol.3, No.4, pp. 259-267, 2015, DOI:10.7569/JRM.2014.634137

Abstract Single-ply biocomposite laminates were fabricated with two different woven fabrics and a bio-based resin using a wet layup technique at room temperature. A highly elastic, stockinette weave bamboo fiber fabric and a thicker, inelastic plain weave bamboo fabric were both investigated. The elastic fabric was pre-strained at 25% intervals, ranging from 0–100% of its original length. Samples made with E-Glass and S-Glass, two common glass fiber reinforcements, were also fabricated using the bioresin as benchmarks. The ultimate strength and modulus of elasticity characteristics of the composites were determined using the ASTM D3039/ D3039M-08 standard test… More >

W.H. Chen¹, H.C. Cheng^2,3, C.F. Yu^1,3

CMES-Computer Modeling in Engineering & Sciences, Vol.109-110, No.1, pp. 1-13, 2015, DOI:10.3970/cmes.2015.109.001

Abstract This study aims at exploring the interfacial adhesion strength between solder bump and four typical under bump metallurgies (UBMs), i.e., Cu/Ni, Cu/TiW, Cu/Ni/Cr and /Cu/V/Cr, at atomistic scale. The average bond length and interfacial adhesion stress of the Sn-3.5Ag/Cu/Ni, Sn-3.5Ag/Cu/TiW, Sn-3.5Ag/Cu/Ni/Cr and Sn-3.5Ag/Cu/V/Cr micro-bump interconnects are calculated through the firstprinciples density functional theory (DFT) calculation to estimate the interfacial adhesion strength between the solder bump and UBMs. In addition, by investigating the electric field effect on the average bond length and adhesive stress, the combination of solder bump and UBM with better interfacial adhesion strength… More >

Xuwen An^1,2, Jianguo Hou³, P.D. Gosling⁴, Dong Dai⁵, Long Xiao⁶, Xiaoyi Zhou⁷

CMES-Computer Modeling in Engineering & Sciences, Vol.107, No.1, pp. 1-25, 2015, DOI:10.3970/cmes.2015.107.001

Abstract Studies on the theory of structural system reliability includes identification of main the failure modes and calculation of inclusive failure probabilities for the structural system. The efficient and accurate identification of failure modes in structural systems is difficult and represents a key focus for research in system reliability. The fundamental theory of the branch and bound algorithm for stage critical strength is reviewed in this paper. Some deficiencies in this method are highlighted. Corresponding approaches to overcome these deficiencies are proposed. Calculated system reliability solutions to the classical model, a truss with 10 elements, indicate More >

Joo Shin Park¹, Jung Kwan Seo^2,3

CMES-Computer Modeling in Engineering & Sciences, Vol.106, No.4, pp. 291-308, 2015, DOI:10.3970/cmes.2015.106.291

Abstract Ships, ship-shaped offshore structures, land-based structures and aerospace structures typically consist of various curved plate components. It is difficult to simulate the buckling and post-buckling of curved thin and/or thick plates that have characteristics of nonlinear structural mechanics, such as nonlinear behaviour when loading is applied. The elastic post-buckling behaviour of a curved plate is very complex, and accompanied by mode changes due to the occurrence of secondary buckling behaviour. Therefore, it is very important to clarify the elastic post-buckling behaviour when subjected to axial loading. The aim of this study was to derive an More >

Q.W. Yang¹, S.G. Du^1,2

CMC-Computers, Materials & Continua, Vol.47, No.3, pp. 217-236, 2015, DOI:10.3970/cmc.2015.047.217

Abstract Size effect is a major issue in concrete structures and occurs in concrete in any loading conditions. In this study, size effect on concrete cubic compressive strength is modeled with a back-propagation neural network. The main advantage in using an artificial neural network (ANN) technique is that the network is built directly from experimental data without any simplifying assumptions via the self-organizing capabilities of the neural network. The proposed ANN model is verified by using 27 experimental data sets collected from the literature. For the large specimens, a modified ANN is developed in the paper More >

N. Ma^1,2, K. Sato³, K. Takada⁴

CMC-Computers, Materials & Continua, Vol.46, No.3, pp. 195-219, 2015, DOI:10.3970/cmc.2015.046.195

Abstract The local mechanical behaviors of advanced high strength steels undergoing a very large strain from uniform plastic deformation to fracture were investigated with the aid of a measured displacement field and a measurement based FEM. As a measurement method, a digital image grid method (DIGM) was developed and the three-direction transient displacement field on uniaxial tensile test pieces was measured. Combining the measured transient displacement field with the finite element method, a measurement based FEM (M-FEM) was developed for the computation of distribution of the local strains, local stresses and ductile damage accumulation in a More >

P. Sittisart^1,*, M.M. Hyland¹, M.A. Hodgson¹, C. Nguyen², A. Fernyhough³

Journal of Renewable Materials, Vol.2, No.4, pp. 264-269, 2014, DOI:10.7569/JRM.2014.634123

Abstract A series of composites based on polypropylene with different loadings of nickel-coated cellulose fi bres (NCCF) were fabricated with the aim to create a composite suitable for EMI shielding and/or electrostatic discharge application. Various properties such as EMI shielding effectiveness, surface resistivity, volume resistivity and fl exural strength were characterised according to ASTM standard. Both surface and volume resistivity suggested that the electrical conductivity of NCCF was not high enough and the composite remains electrically non-conducting up to 40 wt% loading of NCCF. However, nickel particles were still able to shield electromagnetic radiation regardless of More >