Search results

1 – 10 of over 2000
Article
Publication date: 16 July 2024

Jinming Zhen, Congcong Zhen, Min Yuan, Yingliang Liu, Li Wang, Lin Yuan, Yuhan Sun, Xinyue Zhang, Xiaoshu Yang and Haojian Huang

With the rapid development of the pipeline transportation and exploitation of mineral resources, it is urgent requirement for the high-performance polymer matrix composites with…

Abstract

Purpose

With the rapid development of the pipeline transportation and exploitation of mineral resources, it is urgent requirement for the high-performance polymer matrix composites with low friction and wear to meet the needs of solid material transportation. This paper aims to prepare high-performance ultrahigh molecular weight polyethylene (UHMWPE) matrix composites and investigate the effect of service condition on frictional behavior for composite.

Design/methodology/approach

In this study, UHMWPE matrix composites with different content of MoS2 were prepared and the tribological performance of the GCr15/composites friction pair in various sliding speeds (0.025–0.125 m/s) under dry friction conditions were studied by ball-on-disk tribology experiments.

Findings

Results show that the frictional behavior was shown to be sensitive to MoS2 concentration and sliding velocity. As the MoS2 content is 2 Wt.%, composites presented the best overall tribological performance. Besides, the friction coefficient fluctuates around 0.21 from 0.025 to 0.125 m/s sliding speed, while the wear rate increases gradually. Scanning electron microscopy images, energy-dispersive spectroscopy and Raman Spectrum analysis present that the main wear mechanisms were abrasive and fatigue wear.

Originality/value

The knowledge obtained herein will facilitate the design of UHMWPE matrix composites with promising self-lubrication performances which used in slag transport engineering field.

Details

Industrial Lubrication and Tribology, vol. 76 no. 6
Type: Research Article
ISSN: 0036-8792

Keywords

Article
Publication date: 5 August 2024

Christopher Igwe Idumah, Raphael Stone Odera and Emmanuel Obumneme Ezeani

Nanotechnology (NT) advancements in personal protective textiles (PPT) or personal protective equipment (PPE) have alleviated spread and transmission of this highly contagious…

Abstract

Purpose

Nanotechnology (NT) advancements in personal protective textiles (PPT) or personal protective equipment (PPE) have alleviated spread and transmission of this highly contagious viral disease, and enabled enhancement of PPE, thereby fortifying antiviral behavior.

Design/methodology/approach

Review of a series of state of the art research papers on the subject matter.

Findings

This paper expounds on novel nanotechnological advancements in polymeric textile composites, emerging applications and fight against COVID-19 pandemic.

Research limitations/implications

As a panacea to “public droplet prevention,” textiles have proven to be potentially effective as environmental droplet barriers (EDBs).

Practical implications

PPT in form of healthcare materials including surgical face masks (SFMs), gloves, goggles, respirators, gowns, uniforms, scrub-suits and other apparels play critical role in hindering the spreading of COVID-19 and other “oral-respiratory droplet contamination” both within and outside hospitals.

Social implications

When used as double-layers, textiles display effectiveness as SFMs or surgical-fabrics, which reduces droplet transmission to <10 cm, within circumference of ∼0.3%.

Originality/value

NT advancements in textiles through nanoparticles, and sensor integration within textile materials have enhanced versatile sensory capabilities, robotics, flame retardancy, self-cleaning, electrical conductivity, flexibility and comfort, thereby availing it for health, medical, sporting, advanced engineering, pharmaceuticals, aerospace, military, automobile, food and agricultural applications, and more. Therefore, this paper expounds on recently emerging trends in nanotechnological influence in textiles for engineering and fight against COVID-19 pandemic.

Details

International Journal of Clothing Science and Technology, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 0955-6222

Keywords

Article
Publication date: 30 May 2023

Ravikantha Prabhu, Sharun Mendonca, Pavana Kumara Bellairu, Rudolf Charles DSouza and Thirumaleshwara Bhat

This paper aims to report the effect of titanium oxide (TiO2) particles on the physical, mechanical, tribological and water resistance properties of 5% NaOH-treated bamboo…

Abstract

Purpose

This paper aims to report the effect of titanium oxide (TiO2) particles on the physical, mechanical, tribological and water resistance properties of 5% NaOH-treated bamboo fiber–reinforced composites.

Design/methodology/approach

In this research, the epoxy/bamboo/TiO2 hybrid composite filled with 0–8 Wt.% TiO2 particles has been fabricated using simple hand layup techniques, and testing of the developed composite was done in accordance with the American Society for Testing and Materials (ASTM) standard.

Findings

The results of this study indicate that the addition of TiO2 particles improved the mechanical properties of the developed epoxy/bamboo composites. Tensile properties were found to be maximum for 6 Wt.%, and impact strength was found to be maximum for 8 Wt.% TiO2 particles-filled composite. The highest flexural properties were found at a lower TiO2 fraction of 2 Wt.%. Adding TiO2 filler helped to reduce the water absorption rate. The studies related to the wear and friction behavior of the composite under dry and abrasive wear conditions reveal that TiO2 filler was beneficial in improving the wear performance of the composite.

Originality/value

This research paper attempts to include both TiO2 filler and bamboo fibers to develop a novel composite material. TiO2 micro and nanoparticles are promising filler materials; it helps to enhance the mechanical and tribological properties of the epoxy composites and in literature, there is not much work reported, where TiO2 is used as a filler material with bamboo fiber–reinforced epoxy composites.

Details

World Journal of Engineering, vol. 21 no. 4
Type: Research Article
ISSN: 1708-5284

Keywords

Article
Publication date: 21 June 2023

Ravikantha Prabhu, Sharun Mendonca, Pavana Kumara Bellairu, Rudolf Charles D’Souza and Thirumaleshwara Bhat

This paper aims to report the effect of titanium oxide (TiO2) particles on the specific wear rate (SWR) of alkaline treated bamboo and flax fiber-reinforced composites (FRCs…

Abstract

Purpose

This paper aims to report the effect of titanium oxide (TiO2) particles on the specific wear rate (SWR) of alkaline treated bamboo and flax fiber-reinforced composites (FRCs) under dry sliding condition by using a robust statistical method.

Design/methodology/approach

In this research, the epoxy/bamboo and epoxy/flax composites filled with 0–8 Wt.% TiO2 particles have been fabricated using simple hand layup techniques, and wear testing of the composite was done in accordance with the ASTM G99-05 standard. The Taguchi design of experiments (DOE) was used to conduct a statistical analysis of experimental wear results. An analysis of variance (ANOVA) was conducted to identify significant control factors affecting SWR under dry sliding conditions. Taguchi prediction model is also developed to verify the correlation between the test parameters and performance output.

Findings

The research study reveals that TiO2 filler particles in the epoxy/bamboo and epoxy/flax composite will improve the tribological properties of the developed composites. Statistical analysis of SWR concludes that normal load is the most influencing factor, followed by sliding distance, Wt.% TiO2 filler and sliding velocity. ANOVA concludes that normal load has the maximum effect of 31.92% and 35.77% and Wt.% of TiO2 filler has the effect of 17.33% and 16.98%, respectively, on the SWR of bamboo and flax FRCs. A fairly good agreement between the Taguchi predictive model and experimental results is obtained.

Originality/value

This research paper attempts to include both TiO2 filler and bamboo/flax fibers to develop a novel hybrid composite material. TiO2 micro and nanoparticles are promising filler materials, it helps to enhance the mechanical and tribological properties of the epoxy composites. Taguchi DOE and ANOVA used for statistical analysis serve as guidelines for academicians and practitioners on how to best optimize the control variable with particular reference to natural FRCs.

Details

World Journal of Engineering, vol. 21 no. 5
Type: Research Article
ISSN: 1708-5284

Keywords

Article
Publication date: 27 August 2024

Pradeep Kumar Mishra and Jagadesh T.

This study aims to evaluate the low energy impact characteristics of 3D printed carbon fiber thermoplastic and thermoset polymer composite using the Izod impact test. The effects…

Abstract

Purpose

This study aims to evaluate the low energy impact characteristics of 3D printed carbon fiber thermoplastic and thermoset polymer composite using the Izod impact test. The effects of infill density are examined on the Izod impact properties of 3D printed thermoset polymer and thermoplastic composite specimens. Furthermore, a thorough investigation is conducted into the effect of heat treatment using a hot-air oven on both types of 3D printed composite specimens. To characterize the impact characteristics of each specimen, the fracture surfaces caused by impact load are inspected, and the fracture mechanism is studied using scanning electron micrographs.

Design/methodology/approach

Izod Impact specimens of thermoset (epoxy resin) and thermoplastic carbon fiber of different infill density (70, 75, 80, 85, 90 and 100%) are fabricated using the different fiber impregnation 3D printing process. To carry out the heat treatment process, printing of composites is done for each infill design from both thermoset and thermoplastic composites and the impact characteristics of specimens are evaluated on a pendulum test-rig using the ASTM D-256 standard. Using a scanning electron microscope, each fracture zone underwent four separate scanning processes, ranging in size from 2 µm to 100 µm.

Findings

The impact resistance of the 3D printed thermoset and thermoplastic composite material is significantly influenced by the type of fiber placement and infill density in the matrix substrate. Because of the weak interfacial strength between the layers of fiber and polyamide 6, the specimen printed with continuous fiber implanted at the part exhibited reduced impact resistance. At 75% infill density, the impact specimen printed with coextruded fiber showed the highest impact resistance with a 367.02% greater magnitude than the continuous fiber specimen with the same infill density.

Originality/value

This work presents a novel approach to analyze the low energy impact characteristics and three-dimensional printing of carbon fiber reinforced thermoplastic and carbon fiber reinforced thermoset and thermoplastic composite material.

Details

Rapid Prototyping Journal, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 1355-2546

Keywords

Article
Publication date: 23 August 2024

Yunhao Li, Qian Wei and Luxian Li

We use the extended finite element method (XFEM) to model the whole process of initiation and propagation of cracks in the inner dense pyrolytic carbon (IPyC) layer of…

Abstract

Purpose

We use the extended finite element method (XFEM) to model the whole process of initiation and propagation of cracks in the inner dense pyrolytic carbon (IPyC) layer of tri-structural isotropic (TRISO) particle induced by the microdefect in an irradiation-induced thermomechanical coupling environment and study the effect of microdefect sizes on the propagation path.

Design/methodology/approach

The irradiation-induced thermal–mechanical coupling analysis is first conducted for the representative volume element (RVE) of the TRISO particle by using the conventional finite element method (CFEM) so that the stress distribution is obtained. The stress results are then restored for the enriched elements, and the simulation of crack initiation and propagation is eventually carried out by using the XFEM.

Findings

1. As a crack initiates in the IPyC layer, it will terminate at the free edge of the RVE TRISO particle in the end. 2. The size of the microdefect has a significant impact on the propagation path.

Originality/value

The ceramic dispersion microencapsulated (CDM) fuel is a good accident-resistant fuel whose safe operation is crucial to the safety and reliability of the whole nuclear reactor. It is of great scientific significance and practical value to study the irradiation-induced thermomechanical coupling stress distribution and cracking behavior in the IPyC layer of TRISO particles for the CDM fuel. Crack initiation and propagation analysis is challengeable for this complex multi-layer structure. This can help understand the failure mechanism of TRISO particles and evaluate the operation safety of the reactor.

Details

Engineering Computations, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 0264-4401

Keywords

Article
Publication date: 18 July 2024

Eddy Balemba Kanyurhi, Deogratias Bugandwa Mungu Akonkwa, Bonheur Murhula Lusheke, Patrick Murhula Cubaka, Paul Kadundu Karhamikire and Célestin Bucekuderhwa Bashige

The study has two objectives: (1) expand our knowledge of the relationship between unethical behaviour and both trust and satisfaction and (2) demonstrate that unethical behaviour…

Abstract

Purpose

The study has two objectives: (1) expand our knowledge of the relationship between unethical behaviour and both trust and satisfaction and (2) demonstrate that unethical behaviour research should be examined multi-dimensionally.

Design/methodology/approach

Data were collected by resorting to a mixed methods approach. First, individual interviews were performed with 31 bank consumers from six main commercial banks in Bukavu city in the Democratic Republic of the Congo. Interview notes were submitted for content analysis to identify items and components that underpin the unethical practices construct. Second, a quantitative survey was conducted with 410 consumers from the same six banks. An aggregated-disaggregated structural equations modelling approach was used to test the impact of unethical practices on relationship outcomes through two studies. Study 1 tested a model that links unethical behaviour as a one-dimensional construct to trust and satisfaction. Study 2 tested a model that directly connects the four specific unethical behaviour components to both trust and satisfaction.

Findings

Results from study 1 reveal that perceived unethical behaviour negatively influences consumer trust. Results also confirm that trust positively influences customer satisfaction. Results from study 2 confirm that unresponsive, disrespect and lying behaviours negatively influence both trust and satisfaction. Banks which are involving in those specific unethical behaviours can neither satisfy their consumers, nor maintain a sustainable and profitable relationship with them. Therefore, unethical behaviours harm the relationships outcomes in the banking sector.

Research limitations/implications

The perceived unethical behaviour scale derives from a single data set and its reliability and validity need to be improved. Relationships between constructs are tested in a more direct way and ignore moderating variables. Perceived unethical behaviour is connected to relationship outcome variables while its impact on firms’ metrics have been ignored.

Practical implications

Banks have to understand customers’ perception of unethical behaviours and find a way to overcome them. Banks should recruit, motivate and retain employees who demonstrate an ethical inclination in the service encounter and create structures and mechanisms in order to monitor and manage unethical practices.

Social implications

Banks employees' unethical behaviour and practices not only damage the trust and reputation of banks but also can lead to frustration on the part of customers and damage their relationship with the institution. Our paper is a warning of this danger and might improve the social interactions between organisations (in general) and customers.

Originality/value

Unethical behaviour is measured with a four-component scale in contrast to previous studies that have used bi-dimensional or one-dimensional scales. The study tests a disaggregated model that links four components of perceived unethical behaviour to relationship outcome variables. Perceived unethical behaviours are analysed from the customers’ perspective by resorting to mixed methods strategy.

Details

International Journal of Bank Marketing, vol. 42 no. 6
Type: Research Article
ISSN: 0265-2323

Keywords

Article
Publication date: 2 August 2024

Peng Cai, Pingjie Zhang, Xiong Xiao, Wenneng Yang, Xiaohan Wu, Lingli Ni and Fei Zheng

The purpose of this paper is to investigate the effect of mullite on the mechanical properties and friction of carbon fiber (CF)-reinforced friction material.

Abstract

Purpose

The purpose of this paper is to investigate the effect of mullite on the mechanical properties and friction of carbon fiber (CF)-reinforced friction material.

Design/methodology/approach

CF-reinforced friction materials with varying content of mullite were fabricated by hot press molding, and then the tribological properties were tested on the MRH-3-type tribometer under ambient conditions with the ring-on-block configuration.

Findings

The experimental results indicated that the addition of mullite increased the density and compressive strength of friction material. However, the flexural strength of friction material decreased by 16% with the addition of 15 Wt.% mullite. The friction coefficient was proportional to the mullite content. Friction material with 12.5 Wt.% mullite showed the highest friction stability under different loads, whereas friction material with 10 Wt.% mullite exhibited the highest friction stability under different sliding speeds.

Originality/value

By boosting the resistance to deformation under load and increasing the specific heat capacity, mullite contributed significantly to the friction stability of the friction material.

Details

Industrial Lubrication and Tribology, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 0036-8792

Keywords

Article
Publication date: 26 June 2024

H Radi, Khaled F. El-Nemr, Salwa M. Elmesallamy and Enas Amdeha

This study aims to prepare activated carbon (AC) and activated biochar (BC) from sugarcane bagasse (SCB) can be used as carbon black (CB) replacement for styrene butadiene rubber…

Abstract

Purpose

This study aims to prepare activated carbon (AC) and activated biochar (BC) from sugarcane bagasse (SCB) can be used as carbon black (CB) replacement for styrene butadiene rubber (SBR) composites cured by electron beam (EB) radiation.

Design/methodology/approach

This study is carried out to investigate the effect of partial replacement of CB (as traditional filler) by AC or BC prepared from low-cost agricultural wastes (SCB) to improve the properties of SBR rubber cured by EB radiation (doses from 25 to 150 kGy).

Findings

The results indicated that the addition of AC or BC leads to improve the physical and mechanical properties of SBR with increasing irradiation dose [especially at concentration of 10 parts per hundred part of rubber (phr) from BC]. Also in this study, this paper examines how exposure of SBR rubber composites to ultraviolet (UV) radiation changes the mechanical properties for these composites, to do that, the specimens were examined before and after they were exposed to UV radiation for 300 h. The results showed that, the irradiated SBR composites, UV exposure, exhibit better retention in mechanical properties as compared with unirradiated ones, and the samples loaded with CB hybrid with ACs had an increased value of tensile strength (TS) retention as compared with blank sample.

Originality/value

The importance of this study is that, the production of AC from SCB offers a huge opportunity to overcome the problem of the disposal of SCB.

Details

Pigment & Resin Technology, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 0369-9420

Keywords

Article
Publication date: 26 August 2024

Made Indra Wijaya

This study aims to investigate the conceptual relationship between full-range leadership theory (FRLT) and patient safety culture in primary care settings, aiming to understand…

Abstract

Purpose

This study aims to investigate the conceptual relationship between full-range leadership theory (FRLT) and patient safety culture in primary care settings, aiming to understand how leadership styles influence the development and sustainability of a culture prioritizing patient safety.

Design/methodology/approach

Using a conceptual analysis approach, the study builds a theoretical framework that integrates FRLT – which includes transformational, transactional and laissez-faire leadership styles – with the elements of patient safety culture. This framework serves as the basis for a comprehensive literature review, allowing for the formulation of hypotheses regarding the impact of each leadership style on patient safety culture.

Findings

The analysis demonstrates that transformational leadership bolsters patient safety culture by fostering open communication, encouraging error reporting and facilitating continuous improvement. Transactional leadership yields mixed effects, effectively supporting compliance and operational outcomes but showing limitations in promoting a proactive safety culture. Conversely, laissez-faire leadership is associated with negative outcomes for patient safety culture, mainly due to its passive and detached approach.

Originality/value

The originality of this study is rooted in its focused examination of FRLT’s impact on patient safety culture within primary care settings, the development of a unique conceptual framework and its contribution of actionable insights for health-care leadership. These elements collectively advance the understanding of how leadership can enhance patient safety culture, providing a solid foundation for future research and practical application in primary care environments.

Details

Leadership in Health Services, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 1751-1879

Keywords

1 – 10 of over 2000