Xinlei Gao, Tingting Wang and Zhong Cheng
Ultra-high molecular weight polyethylene (UHMWPE) has an excellent performance and application value; however, as a tribological material, its main drawback is its poor…
Abstract
Purpose
Ultra-high molecular weight polyethylene (UHMWPE) has an excellent performance and application value; however, as a tribological material, its main drawback is its poor performance under dry friction, impacting its ability to work in high-speed dry friction conditions. Modification of UHMWPE can be carried out to overcome these issues. A significant number of inorganic materials have been used to modify UHMWPE and provide it with good tribological performance. However, thus far, there has been no systematic investigation into the methodology of modifying UHMWPE. The authors take a quantitative approach to determine the structure tribo-ability relationship and basic principles of screening of inorganic compounds suited to modify UHMWPE.
Design/methodology/approach
The tribological properties of modified UHMWPE using a series of inorganic additives have been qualitatively studied by the authors’ research group previously. In this study, basic quantitative structure tribo-ability relationships (QSTRs) of inorganic additives for modifying UHMWPE were studied to predict tribological properties. A set of 15 inorganic compounds and their tribological data were used to study the predictive capability of QSTR towards inorganic additives properties.
Findings
The results show that the anti-wear and friction-reducing properties of these inorganic compounds correlate with the calculated parameters of entropy and dipole moment. Increased entropy and smaller dipole moment can effectively improve the anti-wear and friction-reducing ability of inorganic compounds as UHMWPE additives. Additives with larger molecular weight, lower hardness and lower melting and boiling points provide good tribological properties for UHMWPE. For inorganic compounds to act as UHMWPE additives, the chemical bond should be less covalent and have more ionic character.
Research limitations/implications
Only 15 inorganic compounds and their tribological data were used to study the predictive capability of QSTR towards inorganic additives properties. If the samples number is more than 30, the other QSTR methodology can be used to study the modified UHMWPE, and the models finding can be more precise.
Practical implications
A QSTR model for modified UHMWPE has been studied systematically. While the results are not more precise and detailed, the model provides a new way to explore the modified UHMWPE characteristics and to reveal new insight into the friction and wear process.
Social implications
Because the method of studying tribological materials is entirely different from others, the authors want to present the works and discuss it with colleagues.
Originality/value
The paper presents a new method to study the modified UHMWPE. A QSTR is used to study the tribology capability of compounds from calculated structure descriptors. This study uses the Hartree–Fock ab initio method to establish a QSTR prediction model to estimate the ability of 15 inorganic compounds to act as anti-wear and friction-reducing additives for UHMWPE.
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Bangyao Han, Fenglian Sun, Chi Zhang and Xinlei Wang
This paper aims to investigate the effect of the Cu, Ni and Ag addition in Sn5Sb-based alloy on the mechanical properties and its mechanism.
Abstract
Purpose
This paper aims to investigate the effect of the Cu, Ni and Ag addition in Sn5Sb-based alloy on the mechanical properties and its mechanism.
Design/methodology/approach
The micro-indentation, creeping test of the Cu/Sn5Sb–0.5Cu–0.1Ni–0.5Ag/Cu and Cu/Sn–5Sb/Cu were conducted, and its microstructure was analysed. The scanning electron microscope and the metallographic microscope characterized the microstructure of the Sn5Sb–0.5Cu–0.1Ni–0.5Ag/Cu and Sn–5Sb/Cu joints.
Findings
The microstructure of Cu/Sn5Sb–0.5Cu–0.1Ni–0.5Ag/Cu is distributed with the fine (Cu,Ni)6Sn5 and Ag3Sn intermetallic compounds (IMCs), whereas the Cu6Sn5 and Sn3Sb2 in Cu/Sn–5Sb/Cu is larger and far more less. This investigation reveals that the addition of the Cu, Ni and Ag elements reinforced mechanical properties and provided a technical basis for the development of Sn–Sb alloy with good mechanical properties.
Originality/value
This paper reveals that the hardness and the modulus of the bulk solder Cu/Sn–5Sb/Cu solder joints were improved with the addition of Cu, Ni and Ag trace elements. Meanwhile, the creep resistance and plasticity were also improved. This study has a great value for exploring high-performance Sn–Sb based solder alloy and has proved an example.
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Xin Qi, Xinlei Lv, Zhigang Li, Chunbaixue Yang, Haoran Li and Angelika Ploeger
Understanding young adults’ organic food purchasing behavior in the fresh food e-commerce platforms (FFEP) is crucial for expanding the global environmental product market. The…
Abstract
Purpose
Understanding young adults’ organic food purchasing behavior in the fresh food e-commerce platforms (FFEP) is crucial for expanding the global environmental product market. The study aims to investigate how specific characteristics of platforms and organic food information impact young adults’ perceived value, leading to their subsequent purchase intention.
Design/methodology/approach
Around 535 valid responses were collected through an online survey and then analyzed applying a two-stage structural equation model (SEM) and artificial neural network (ANN) approach.
Findings
Results of this research show that platform characteristics (including system quality and evaluation system) and product information characteristics (including organic label, ingredient information and traceability information) significantly affect young adults’ perceived utilitarian and hedonic value. The platform’s service quality has a strong effect on their perceptions of hedonic value, while the delivery system strongly influences their utilitarian value. Moreover, the perceived value, as a crucial mediator, plays a significant role in moderating the influence of platform and product information characteristics on the purchase intentions of young consumers regarding organic food.
Originality/value
Previous research has overlooked the credence attributes of organic food and particularities of online purchasing, focusing instead on general platform and product characteristics. This study addresses this gap by proposing a more appropriate model that integrates the characteristics of both the platform and product information. This offers theoretical and managerial implications for effectively stimulating organic food consumption among young adults in online environments.
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This study investigates the influence of corporate culture on financial reporting transparency within Iranian firms.
Abstract
Purpose
This study investigates the influence of corporate culture on financial reporting transparency within Iranian firms.
Design/methodology/approach
Leveraging a dataset of 1,480 firm-year observations from the Tehran Stock Exchange spanning from 2013 to 2022, the study employs text mining to quantify linguistic features of corporate culture and transparency, specifically readability and tone, within annual financial statements and Management Discussion and Analysis (MD&A) reports.
Findings
Our results confirm a positive and significant relationship between corporate culture and financial reporting transparency. The distinct dimensions of corporate culture — Creativity, Competition, Control, and Collaboration — each uniquely enhance financial transparency. Robustness tests including firm fixed-effects, entropy balancing, Generalized Method of Moments (GMM), and Propensity Score Matching (PSM) validate the profound influence of corporate culture on transparency. Additionally, our analysis shows that corporate culture significantly affects the disclosure of business, operational, and financial risks, with varying impacts across risk categories. Cross-sectional analysis further reveals how the impact of corporate culture on transparency varies significantly across different industries and firm sizes.
Research limitations/implications
The study’s scope, while focused on Iran, opens avenues for comparative research in different cultural and regulatory environments. Its reliance on text mining could be complemented by qualitative methods to capture more nuanced linguistic subtleties.
Practical implications
Findings underscore the strategic importance of cultivating a transparent corporate culture for enhancing financial reporting practices and stakeholder trust, particularly in emerging economies with similar dynamics to Iran.
Originality/value
This research is pioneering in its quantitative analysis of the textual features of corporate culture and its impact on transparency within Iranian corporate reports, integrating foundational theoretical perspectives with empirical evidence.