Yottha Srithep^1,*, Onpreeya Veang-in¹, Dutchanee Pholharn², Lih-Sheng Turng³, John Morris⁴

Journal of Renewable Materials, Vol.9, No.7, pp. 1267-1281, 2021, DOI:10.32604/jrm.2021.015604

Abstract A low-molecular-weight polylactide-poly(butylene succinate) (PLA-PBS) copolymer was synthesized and incorporated into polylactide (PLA) as a novel toughening agent by solvent casting. The copolymer had the same chemical structure and function as PLA and it was used as a plasticizer to PLA. The copolymer was blended with PLA at a weight ratio from 2 to 10 wt%. Phase separation between PLA and PLA-PBS was not observed from their scanning electron microscopy (SEM) images and the crystal structure of PLA almost remained unchanged based on the X-ray diffraction (XRD) measurement. The melt flow index (MFI) of the blends was higher as the… More >

Song Ching Fan¹, Hui-Chuan Shih^2,*, Hui-Chu Tseng³, Kuei-Feng Chang⁴, Wei-Chin Li⁵, An Shin Shia⁶

International Journal of Mental Health Promotion, Vol.23, No.1, pp. 57-73, 2021, DOI:10.32604/IJMHP.2021.012177

Abstract This paper talks about how to insist staying in changed mindset based on the assigned cognitive reframing principles, and finally the changed mindset become a forever psychological status by PSI model proposed by this study. P is the cognitive reframing principle of positive psychology, happiness in this case; S is self-efficacy, which plays the important role in maintaining the stress taker to psychologically stay in the changed mindset in the long run. I represent of insisting power, the mental toughness to against the adverse negative emotions. Improving university students’ stress coping skills through the psychological dynamics formed by cognitive reframing… More >

Mohammad Maghsoudi-Ganjeh, Xiaodu Wang^*, Xiaowei Zeng^*

CMES-Computer Modeling in Engineering & Sciences, Vol.125, No.1, pp. 1-32, 2020, DOI:10.32604/cmes.2020.012123

Abstract In this review, a brief presentation is first given to the hierarchical structure and mechanical behavior of bone. Then, the recent advancements in nanoscale characterization of bone ultrastructure and ingredients are discussed based on an extensive quantity of references in the literature.Moreover, computational and analytical bone mechanics at ultrastructure levels are critically reviewed with the growing body of knowledge in the field. The computational and analytical models are summarized in several categories for ease of understanding bone nanomechanics and their applicability/limitations. This review is expected to provide a well-informed foundation for the researchers interested in interrogating the complex biomechanical response… More >

Kun Li, Xiaona Li, Jing Luo, Jingjing Li, Qiang Gao^*, Jianzhang Li^*

Journal of Renewable Materials, Vol.5, Suppl.1, pp. 31-38, 2017, DOI:10.7569/JRM.2017.634131

Abstract The objective of this study was to use soybean meal and 1,4-butanediol diglycidyl ether (BDDE) to develop a highly water-resistant, soy-based bioadhesive for plywood fabrication. The physical properties and performance characteristics of the resulting adhesive, including solid content, viscosity, water resistance, crystallinity, fracture morphology, thermal behavior, and cracks, were evaluated. The proposed adhesive was compared against the traditional soy adhesive with polyamidoamine-epichlorohydrin (PAE). Results showed that adding 8 g of BDDE into the adhesive formulation improved the solid content up to 32.83% and reduced the viscosity to 27340 mPa·s. The wet shear strength of plywood bonded with the adhesive was… More >

Guocai Chai

Structural Durability & Health Monitoring, Vol.3, No.3, pp. 191-196, 2007, DOI:10.3970/sdhm.2007.003.191

Abstract Duplex stainless steels (DSS) are a group of steels consisting of approximately equal volume fraction of austenite and ferrite. In this study, the influences of the factors such as hydrogen, ferrite phase, cold deformation, grain size, and cluster due to the spinodal decomposition and precipitates or secondary phases in a super duplex stainless steel on the ductile to brittle transition (DBT) are investigated. Three types of DBT curves: toughness versus temperature, hardness and amount of precipitates, have been built to describe the DBT behavior in DSS. These curves are important to provide the information about the critical conditions or criteria… More >

J. Mohan¹, D. Carolan¹, N. Murphy¹, A. Ivankovic¹, D. Dowling¹

Structural Durability & Health Monitoring, Vol.3, No.2, pp. 81-86, 2007, DOI:10.3970/sdhm.2007.003.081

Abstract The aim of this work is to investigate the influence of a variety of plasma treatments on the surface properties of an epoxy-based composite material and to establish a relationship between these properties and the subsequent mechanical behaviour of adhesively bonded joints. To this end, specimens were subjected to three different types of plasma treatment: two short treatments (2min) of He and He plus O₂, and one long treatment (15min) of He plus O₂. The variation in surface energy of the composite specimens was examined in each case over a period of up to 3 days using contact angle measurements.… More >

W. Brocks¹

Structural Durability & Health Monitoring, Vol.1, No.4, pp. 233-244, 2005, DOI:10.3970/sdhm.2005.001.233

Abstract A review on phenomenological fracture criteria is given, based on the energy balance for cracked bodies, and the respective toughness parameters are related to micromechanical processes. Griffith's idea of introducing a "surface energy" and Barenblatt's concept of a "process zone" ahead of the crack tip build the foundation of modern cohesive models, which have become versatile tools for numerical simulations of crack extension. The cohesive strength and the separation energy used as phenomenological material parameters in these models appear to represent a physically significant characterisation of "fracture toughness". Micromechanical interpretations of these parameters can be derived, depending on the specific… More >

R. Moskovic¹, P. E. J. Flewitt^1,2

Structural Durability & Health Monitoring, Vol.1, No.1, pp. 83-94, 2005, DOI:10.3970/sdhm.2005.001.083

Abstract Consideration of the structural integrity is one of the inputs when evaluating potential solutions to plant problems. Structural integrity assessments of components forming the pressure boundaries of nuclear plant evaluate safety margins against cleavage fracture. These assessments consider the reserve factors between the applied stress and fracture toughness of the material as well as temperature margins between the operating temperature and the temperature at which the steel is ductile as defined by upper shelf behaviour. To carry out these structural integrity assessments, estimates of cleavage fracture toughness are required. The approach presented in this paper allows for differences between cleavage… More >

M.N.D. Cherief¹, M. Elmeguenni¹, M. Benguediab¹

CMC-Computers, Materials & Continua, Vol.51, No.3, pp. 187-201, 2016, DOI:10.3970/cmc.2016.051.187

Abstract Impact behavior of polymers has received considerable attention in recent years, and much work based on fracture mechanic approaches has been carried out. In this paper, fracture behavior in large deformation of a high density polyethylene (HDPE) materials was investigated through experimental impact testing on single edge notched specimen (SENB) and by using theoretical and analytical fracture criteria concepts. Moreover, a review of the main fracture criteria is given in order to characterize the toughness of this polymer in the both cases (static and dynamic). The fractured specimens obtained from the Charpy impact test were characterized with respect to their… More >

M. Inomoto^1,*, S. Aihara², T. Kasuya², T. Kawabata², Y. Okazaki¹

The International Conference on Computational & Experimental Engineering and Sciences, Vol.22, No.2, pp. 139-139, 2019, DOI:10.32604/icces.2019.05781

Abstract Prediction of toughness of weld heat-affected zone (HAZ) of steels is a difficult task because it is controlled by many parameters including grain-size, brittle microphase, hardness, etc. No reliable model has been established, yet. In the present study, a numerical model for predicting Charpy impact toughness of weld HAZ of steels has been developed. The model comprises two parts: phase transformation and toughness prediction. In the former part, phase fraction, size distribution of martensite-austenite brittle microphase, hardness, size of grain boundary ferrite and bainitic ferrite plate, etc. are calculated and these parameters are used in the latter part, in which… More >