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The purpose of this paper is to enhance the compatibility of titanium dioxide in epoxy resins and thus the corrosion resistance of the coatings.

In this work, TiO₂ was modified by the mechanochemistry method where mechanical energy was combined with thermal energy to complete the modification. The stability of modified TiO₂ in epoxy was analyzed by sedimentation experiment. The modified TiO₂-epoxy coating was prepared, and the corrosion resistance of the coating was analyzed by open circuit potential, electrochemical impedance spectroscopy and neutral salt spray test.

High-temperature mechanical modification can improve the compatibility of TiO₂ in epoxy resin. At the same time, the modified TiO₂-epoxy coating showed better corrosion resistance. Compared to the unmodified TiO₂-epoxy coating, the coating improved the dry adhesion force by 61.7% and the adhesion drop by 33.3%. After 2,300 h of immersion in 3.5 Wt.% NaCl solution, the coating resistance of the modified TiO₂ coating was enhanced by nearly two orders of magnitude compared to the unmodified coating.

The authors have grafted epoxy molecules onto TiO₂ surfaces using a high-temperature mechanical force modification method. The compatibility of TiO₂ with epoxy resin is enhanced, resulting in improved adhesion of the coating to the substrate and corrosion resistance of the coating.

This paper aims to study the synergistic lubrication effects of Sn–Ag–Cu and MXene–Ti₃C₂ to improve the tribological properties of M50 bearing steel with microporous channels.

M50 matrix self-lubricating composites (MMSC) were designed and prepared by filling Sn–Ag–Cu and MXene–Ti₃C₂ in the microporous channels of M50 bearing steel. The tribology performance testing of as-prepared samples was executed with a multifunction tribometer. The optimum hole size and lubricant content, as well as self-lubricating mechanism of MMSC, were studied.

The tribological properties of MMSC are strongly dependent on the synergistic lubrication effect of MXene–Ti₃C₂ and Sn–Ag–Cu. When the hole size of microchannel is 1 mm and the content of MXene–Ti₃C₂ in mixed lubricant is 4 wt.%, MMSC shows the lowest friction coefficient and wear rate. The Sn–Ag–Cu and MXene–Ti₃C₂ are extruded from the microporous channels and spread to the friction interface, and a relatively complete lubricating film is formed at the friction interface. Meanwhile, the synergistic lubrication of Sn–Ag–Cu and MXene–Ti₃C₂ can improve the stability of the lubricating film, thus the excellent tribological property of MMSC is obtained.

The results help in deep understanding of the synergistic lubrication effects of Sn–Ag–Cu and MXene–Ti₃C₂ on the tribological properties of M50 bearing steel. This work also provides a useful reference for the tribological design of mechanical components by combining surface texture with solid lubrication.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-12-2023-0381/

This paper aims to explore the influence of applied pressure on the tribological properties of the friction component in a wet multi-disc clutch during the running-in process.

The running-in evolutionary was explored in terms of global friction performance. The variation of friction torque and mean COF of the initial 300 engagement cycles was obtained by full-scale tests. Finally, an optical microscope was used to detect the wear characteristics of friction surfaces.

The applied pressure showed a significant influence on the tribological behaviors of wet clutches during the running-in process. The mean COF decreased and then increases with the increase of the applied pressure. A higher applied pressure contributed to more asperity summits being sheared, thus resulting in a smoother surface. Considering a suitable wore performance, properly applied pressure is necessary.

The results provide theoretical guidance for selecting the optimal applied pressure in the running-in of wet clutches.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-08-2022-0256/

Natural gas hydrate (NGH) has been regarded as one of the most important resources due to NGH's large amounts of reserve. However, NGH development still faces many technical challenges, such as low production rate and reservoir instability resulting from NGH decomposition. Therefore, developing a fully coupled THMC model for simulating the hydrate decomposition and studying its mechanical behavior is very important and necessary. The purpose of this article is to develop and solve a multi-phase, strong nonlinearity and large-scale fully coupled thermal-hydro-mechanical–chemical (THMC) model for simulating the multi-physics processes involving solid-liquid-gas flow, heat transfer, NGH phase change and rock deformation during NGH decomposition.

In this paper, a multi-phase, strong nonlinearity and large-scale fully coupled THMC model is developed for simulating the multi-physics processes involving solid-liquid-gas flow, heat transfer, NGH phase change and rock deformation during NGH dissociation. The fully coupled THMC model is solved by using a fully implicit finite element method, in which the gas pressure, water pressure, temperature and displacement are taken as basic unknown variables. The proposed model is validated against with the experimental data, showing high accuracy and reliability.

A multi-phase, strong nonlinearity and large-scale fully coupled THMC model is developed for simulating the multi-physics processes involving solid-liquid-gas flow, heat transfer, NGH phase change and rock deformation during NGH decomposition. The proposed model is validated against with the experimental data, showing high accuracy and reliability.

Some assumptions are made to make the model tractable, including (1) the composition gas of hydrate is pure methane; (2) the gas-liquid multi-phase flow in the pore obeys Darcy's law; (3) hydrate occurs on the surface of soil particles, both of them form the composite consolidation material; (4) the small-strain assumption is applied to composite solid materials, which are treated as skeletons and cannot be moved; (5) momentum change caused by phase change is not considered.

NGH has been regarded as one of the most important resources due to its large amounts of reserve. However, NGH development still faces many technical challenges, such as low production rate and reservoir instability resulting from NGH decomposition. Most of the existing studies decouple the process with solid deformation and seepage behavior, but the accuracy of the numerical results will be sacrificed to certain extent. Therefore, it is very important and necessary to develop a fully coupled THMC model for simulating the hydrate decomposition and studying its mechanical behavior.

NGH, widely distributed in shallow seabed or permanent frozen region, has the characteristics of high energy density and high combustion efficiency (Yan et al., 2020). A total of around 7.5 × 1,018 m³ has been proved to exist around the world and 1 m³ of NGH can release about 160–180 m³ of natural gas (Kvenvolden and Lorenson) under normal conditions. Safely and sustainably extracting NGH commercially can effectively relieve global energy pressure and contribute to achieving carbon reduction goals.

The novelty of the present work lies in mainly two aspects. First, a fully coupled THMC model is developed for studying the multi-physics processes involving solid-liquid-gas flow, heat transfer, NGH phase change and solid deformation during NGH dissociation. Second, the numerical solution is obtained by using a fully implicit finite element method (FEM) and is validated against experimental data.

This study examines the relationship between green intellectual capital (GIC) and competitive advantage (CA) and proposes the moderating role of corporate philanthropy types (cash, in-kind and both) during the COVID-19 pandemic. In particular, this study investigates the types of corporate philanthropy, strengthening the link between GIC and CA for Chinese listed firms during a pandemic.

Cross-sectional data were collected from 248 chief executive officers (CEOs) of Chinese firms listed on the Shanghai Stock Exchange through a structured questionnaire. Regression analysis was employed to test the proposed hypotheses.

The findings reveal that all types of GIC positively influence a firm's CA. Furthermore, all three types of philanthropy – cash, in-kind and both – moderate the relationship between GIC and CA. However, the intensity of moderation was higher in the case of in-kind philanthropy than in the other two types.

To the best of the authors' knowledge, this is the first empirical study to examine the relationship between GIC (considering its three components: human, structural and relational capital) and CA in China. The study finds different types of philanthropy as moderating variables to better explain the relationship between GIC and CA. Further, it contributes to a new line of research that aims to study philanthropic aspects connected to the GIC debate.

This paper aims to investigate magnetic impacts on bioconvection flow within a porous annulus between an outer cylinder and five inner cylinders. The annulus is filled by oxytactic microorganisms and nano-encapsulated phase change materials.

The modified ISPH method based on the time-fractional derivative is applied to solve the regulating equations in Lagrangian dimensionless forms. The pertinent factors are bioconvection Rayleigh number Ra_b (1–100), circular cylinder’s radius R_c (0.1–0.3), fractional time derivative α (0.95–1), Darcy parameter Da (10⁻⁵–10⁻²), nanoparticle parameter ϕ (0–0.1), Hartmann number Ha (0–50), Lewis number Le (1–20), Peclet number Pe (0.1–0.75), s (0.1–0.9), number of cylinders N_Cylinders (1–4), Rayleigh number Ra (10³–10⁶) and fusion temperature θ_f (0.005–0.9).

The simulations revealed that there is a strong enhancement in the velocity field according to an increase in Ra_b. The intensity and location of the phase zone change in response to changes in θ_f. The time-fractional derivative a acting on a nanofluid velocity and flow characteristics in an annulus. The number of embedded cylinders N_Cylinders is playing a significant role in the cooling processes and as N_Cylinders increases from 1 to 4, the velocity field’s maximum reduces by almost 33.3%.

The novelty of this study is examining the impacts of the magnetic field and the presence of several numbers of embedded cylinders on bioconvection flow within a porous annulus between an outer cylinder and five inner cylinders.

This study aims to investigate the ecological awareness of Chinese consumers towards fast fashion and examine the effect of social sustainability claims on green brand image and purchase intentions in China, considering China’s unique environmental policy landscape and its significant role in the global fast fashion industry. The study explores the role of altruistic values in promoting sustainability within the well-known fast fashion brand “H” and how they shape brand image, consumer satisfaction and brand equity.

The study collected data from 257 Chinese participants and used a serial mediation model through the PROCESS macro in SPSS to analyse the correlation between green brand image, created through sustainability claims and consumer purchase intentions. The model also assessed the intermediary effects of brand image, satisfaction and equity.

The findings of the research indicate a direct and positive relationship between green brand image and consumer purchase intentions, emphasising the need for clothing and textile industry marketers to strategically promote altruistic values in their sustainability efforts and highlighting the importance of ecological awareness in shaping consumer behaviour in the Chinese context. This approach enhances green satisfaction and green brand equity and ultimately leads to higher green purchase intentions.

This study provides significant insights into the effectiveness of incorporating social sustainability claims in advertising to improve a brand’s green image and influence consumer behaviour. It emphasises the importance of altruistic values in sustainability strategies, offering valuable guidelines for marketers in enhancing green satisfaction and brand equity, thereby boosting consumer purchase intentions in the context of green branding and sustainability advertising. Focussing specifically on the Chinese market, this research sheds light on the impact of ecological awareness among Chinese consumers within the fast-fashion industry. Given China’s substantial role in shaping global fast-fashion production and its evolving environmental policies, this focus adds significant depth to our understanding of sustainability claims’ influence within this crucial consumer base.

In this paper, the authors study the production and pricing decisions of a remanufacturing supply chain composed of a supplier, an assembler and a remanufacturer, in which the remanufacturing of components requires patent licensing from the supplier.

The authors consider three different models with government subsidy for remanufacturing: (1) no government subsidies; (2) the government subsidizes the remanufacturing behavior of the supplier and (3) the government subsidizes the remanufacturing behavior of the remanufacturer and use the Stackelberg game model to solve and analyze the equilibrium wholesale prices of components and the equilibrium outputs of new and remanufactured products under three subsidy modes.

The results show that the equilibrium wholesale prices of two kinds of components decrease with the unit patent licensing fee and the unit government subsidy, and the equilibrium quantity of the remanufactured products under the three modes is obviously higher than that of the new products.

Finally through numerical simulation, it is found that the equilibrium profits of the supplier, the manufacturer and the supply chain increase monotonously in relation to the unit government subsidy, while the optimal profit of the assembler in relation to the unit government subsidy tends to decrease first and then increase.

Following the COVID-19 pandemic, the upward trend of organic food (OF) consumption is no longer restrained to western markets but has also extended to emerging markets in different parts of the world. Still, extent post-pandemic literature has devoted little attention to the factors shaping consumers' intent to purchase organic food in developing markets. The current research empirically investigates the antecedents of consumers' attitude and intent to purchase organic food in an emerging market context (i.e. Morocco). This research also explores the differences between OF consumers' manifest attitudes prior to and following the COVID-19 pandemic.

To achieve the study's objectives, data were collected from 1,060 Moroccan respondents using online self-administered questionnaires in two different eras: prior to the COVID-19 pandemic with a total of 441 valid responses and following the pandemic with 619 valid responses. Confirmatory factor analysis (CFA) was employed to validate the data, and a partial least squares (PLS) estimation was used to test the hypotheses.

First, attitude towards OF has a significant impact on consumers' purchase intention; at the same time, it is influenced by subjective norms, organic labeling, perceived behavioral control, health consciousness, and environmental concern. This study's findings also suggest subjective norms, organic labeling, perceived behavioral control, health consciousness, environmental concern, age, and income as the key determinants of consumers' intention to purchase OF. Second, the IPMA analysis suggests that while health consciousness, organic labeling and perceived behavioral control are the most important constructs influencing attitude towards OF, consumers' purchase intention is mostly influenced by health consciousness, attitude towards OF and age. Finally, the PLS-Multigroup Analysis conveyed few discrepancies in the results when comparing the two eras (i.e. subjective norms and age had more significant impacts on consumers' purchase intent following the COVID-19 pandemic).

This study provides organic food retailers and practitioners with a deeper understanding of the key aspects shaping consumers' intent to purchase organic products in emerging markets. The comparative analysis will also provide important insights on how to shape consumers' attitudes and purchase intentions in a new-normal marked by the COVID-19 pandemic.

This study's findings contribute to the growing literature on consumers' behavior in the organic food industry, particularly in developing countries where research is still narrow. This study's study is the first of its kind to compare consumers' intention to purchase organic food before and following the COVID-19 pandemic.

This study aims to present a type of metamorphic mechanism-based quadruped crawling robot. The trunk design of the robot has a metamorphic mechanism, which endows it with excellent crawling capability and adaptability in challenging environments.

The robot consists of a metamorphic trunk and four series-connected three-joint legs. First, the walking and steering strategy is planned through the stability and mechanics analysis. Then, the walking and steering performance is examined using virtual prototype technology, as well as the efficacy of the walking and turning strategy.

The metamorphic quadruped crawling robot has wider application due to its variable trunk configuration and excellent leg motion space. The robot can move in two modes (constant trunk and trunk configuration transformation, respectively, while walking and rotating), which exhibits outstanding stability and adaptability in the examination and verification of prototypes.

The design can enhance the capacity of the quadruped crawling robot to move across a complex environment. The virtual prototype technology verifies that the proposed walking and steering strategy has good maneuverability and stability, which considerably expands the application opportunity in the fields of complicated scene identification and investigation.