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This paper aims to study the thermal oxidation performance of antioxidant additives in ester base oils deeply.

ReaxFF molecular dynamics was used to simulate the thermal oxidation process of butyl octyl diphenylamine and octadecyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl) propanoate as two antioxidant additives act on the Trimethylolpropane trioleate (TMPTO) base oil. Meanwhile, combining with the infrared spectroscopy characterization results of the thermal oxidation test, this paper provides theoretical support for the development of high-performance synthetic lubricants and their antioxidant additives.

The results show that butyl octyldiphenylamine easily removes the hydrogen atom on the secondary amine, which promotes the formation of more long carbon chain diene radicals or polyene hydroperoxides from TMPTO. Octadecyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl) propanoate could easily decompose into octadecyl hydroperoxide and 2,6-di-tert-butyl 4-propionylphenol, which could convert into 2-tert-butyl-4-peroxyethyl-6-hydroperoxy-tert-butylphenol in the middle of the thermal oxidation reaction, prompting TMPTO to form more short-chain alkenyl and olefin hydroperoxide or other oxide.

The main change characteristics of base oil molecules are the first thermal decomposition to form oleic acid groups and ethane cyclopropane methyl oleate. Under the action of butyl octyldiphenylamine and octadecyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl) propanoate, the deep oxidation and decomposition reaction are slowed down.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-01-2020-0037/

This paper aims to focus the synchronous chemical conversion technology–based titanium/zirconium composite on 6061, 7075 aluminum alloys and galvanized steel.

The effects of pH, temperature, reaction time and other process parameters on the corrosion resistance of the three metal surface coatings were investigated by copper sulfate drop and electrochemical corrosion performance tests under a certain content of H2TiF6 and H2ZrF6. The surface morphology and element distribution of the conversion coating were analyzed by scanning electron microscope and X-ray photoelectron spectroscopy.

The results show that the optimal synchronization chemical conversion conditions of 6061/7075 aluminum alloys/galvanized steel are controlled as follows: H2TiF6 2.2 mL/L, H2ZrF6 1 mL/L, pH 3.9, conversion temperature 35°C and conversion time 120 s.

Multi-metals chemical conversion coating can be obtained simultaneously with uniform corrosion resistance and surface morphology. The presence of microdomain features in multiple metals facilitates simultaneous chemical conversion into coatings.

Based on cognitive appraisal theory of stress, this study develops an integrated model to examine the double-edged sword effect and boundary conditions of the impact of organizational crisis on employee behavior.

This study collected 672 employees’ data through three stages of longitudinal follow-up. Hierarchical regression analysis and SPSS macro process were used to test the hypotheses.

The paper finds that organizational crisis induces unethical pro-organizational behavior through enhanced job insecurity and foster taking charge by stimulating career calling. Employee resilience negatively moderates the relationship between organizational crisis and job insecurity as well as the indirect effects of organizational crisis on unethical pro-organizational behavior through job insecurity. Conversely, it positively moderates the association between organizational crisis and career calling and the indirect effects on taking charge through career calling.

This study not only expands the research on the mechanisms of organizational crisis' effects on employees' behaviors but also provides practical guidance for corporate managers on how to respond to organizational crisis.

The following insights are available to organizations and managers: first, this study confirms that organizational crisis can be perceived as threatening stressors that create job insecurity, which in turn leads to pro-organizational unethical behavior. Therefore, managers in organizational crisis should focus on stress regulation and guidance, pay timely attention to changes in the mindset of employees to reduce job insecurity, and strictly prohibit unethical pro-organizational behavior. They should promptly calm and control the atmosphere of panic and anxiety in the organization, do a good job of coordinating the division of labor, reduce personnel conflicts and contradictions, create a good organizational climate and reduce employees' sense of stress and negative perceptions of organizational crisis, thus reducing job insecurity and being able to meet the challenges in a better state. Secondly, this study confirms that employees also perceive organizational crisis as challenges and develop career calling, which in turn inspires proactive change behaviors. This suggests that managers in organizational crisis should promote the positive perception of organizational crisis as challenge, stimulate the career calling of employees in organizational crisis and call on and encourage employees to actively adopt taking charge. Therefore, managers should promptly give employees work affirmation, rewards and punishments, enhance the sense of participation and intrinsic motivation of subordinates, improve self-efficacy and self-confidence levels, effectively reduce the negative perception of organizational crisis, awaken positive psychological energy within individuals, increase their sense of belonging to the organization and thus, increase employees' awareness of the positive challenges of organizational crisis, stimulate employees' career calling through positive and optimistic beneficial pressure drive them to lead the corresponding changes in the crisis. Finally, this study confirms that employees' own resilience can change the double-edged sword effect of organizational crisis. Employees with high resilience are more likely to see organizational crisis as challenge and are thus more likely to develop career calling and are more inclined to initiate change, while employees with low resilience are more likely to see organizational crisis as threat, are more negatively affected by them, develop greater job insecurity and are, thus, more inclined to commit unethical pro-organizational behaviors. This reflects the fact that organizations should constantly cultivate employees' resilience and enhance their cognitive toughness at the same time. For instance, the organization can regularly use promotional lectures and scenarios to help leaders and employees establish corporate ethics, strengthen moral beliefs and correctly understand the nature of unethical affinity behavior. Managers should encourage and advocate positive and correct behaviors such as overcoming difficulties, positive innovation and positive suggestions to promote the sustainable and healthy development of the organization.

The results of this study can increase the organization’s understanding of the negative effects of crisis, help the organization take measures to manage and guide the employees in organizational crisis, more effective and targeted functional changes within the organization, reduce stress damage and improve the efficiency and effectiveness of crisis management. It is also beneficial to improve competitiveness and foresight in the organization’s industry and enhance organizations and employees’ resilience.

This study explores the double-edged sword effect of organizational crisis on employees’ behavior from the perspective of the cognitive appraisal theory of stress, which theoretically opens up a new research perspective, enriches the research in the fields of organizational crisis and taking charge, pro-organizational unethical behavior relationship and practically provides theoretical guidance for enterprises and managers on how to effectively respond to organizational crisis from the employees, which is of great practical significance.

To enhance the load capacity and dynamic characteristics of gas foil conical bearings (GFCBs), two kinds of microgrooves (sector and Fibonacci-like shape) are arranged on the top foil surface.

The Reynolds equation considering gas rarefaction effect is solved by the finite difference method, in which the 2D plate element stiffness model is used for the grooved top foil. The influence of groove on the static characteristics is studied, and the dynamic characteristics of novel bearing are obtained by the perturbation method.

The results show that the gas rarefaction effect on the load capacities is negligible, and the novel GFCB with microgrooved top foil has higher load capacities. Moreover, the deeper groove is conductive to the dynamic stability improvement. The positive Fibonacci-like groove seems to be the most suitable shape, which can largely increase the axial load capacity with little additional torque cost. And the improvement of dynamic characteristics for the Fibonacci-like grooved GFCB is also more favorable.

As the low cost of groove processing, it is an effective way to improve GFCB’s performance and even can be used to upgrade the bearings in service.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-04-2024-0148/

Many of the original buildings have gradually declined because of the development of society and the adjustment of industrial structure. Protecting the classical architecture and restoring the original luster of a building to maintain its own youth has become a hot issue in the current architectural planning. In this paper, the performance of the core idea of building conservation in the specific design and planning was discussed through the in-depth understanding of William Sumner Appleton's architectural concept in building protection planning area. Moreover, the profound influence of the idea of building conservation in building conservation was summarized. The current pace of urbanization development process is rapid, thus, many of the original buildings are severely damaged because of many factors. The concept and thought of William Sumner Appleton were re-interpreted based on the design and planning method of World Expo industrial clusters in Shanghai. This study is of great significance for the promotion of historical building protection and concrete practice in our country.

In practical engineering, oil filters often work under asymmetric cyclic loading. In order to improve the prediction accuracy of fatigue life of the oil filters under asymmetric cyclic loading, the effect of strain ratio and low cycle fatigue plastic deformation on fatigue life need to be considered. This paper aims to discuss the aforementioned objective.

First, strain-controlled fatigue tests with strain ratios of 0, 0.5 and −1 were carried out on the oil filter material 2A70-T6 aluminum alloy, and the test data were used to obtain strain fatigue life curves at three strain ratios. Then, based on the idea of the constant life curve method, the average value of the ratio of the strain amplitude corresponding to different strain ratios under the same partial life was defined as the strain ratio factor. Finally, the elastic-plastic factor was modified by the strain ratio factor, and a new fatigue life prediction model considering the effect of strain ratio was proposed.

The proposed model was validated, respectively, by fatigue test data of 2A70-T6 aluminum alloy, 2124-T851 aluminum alloy and oil filter and the results of the proposed model were compared with the Coffin–Manson equation, Morrow model and Smith–Watson–Topper (SWT) model, showing that the proposed model had higher applicability and accuracy.

In this work, a strain ratio factor is established based on the idea of the constant life curve method, and the strain ratio factor is used to modify the introduced elastic-plastic factor, and then a new fatigue life prediction model considering the influence of strain ratio and low cycle fatigue plastic deformation on material fatigue damage accumulation is proposed. The results show that the prediction results of the proposed model are in good agreement with the experimental data, and the proposed model has good fatigue life prediction ability considering the influence of strain ratio and lays a foundation for the fatigue life prediction of the oil filter.

Cross-border M & A is one of the most important ways of international capital flows, and scholars have paid a lot of attention to this area, but a general explaining model has still not been generated. The purpose of this paper, based on Lambrecht (2004) and Bolton et al. (2013), is to build a general explaining model in this area and use the new model to explain some real world issues.

The model work in this paper is based on Lambrecht’s (2004) real option model, which is the classical modeling method in this area, and take the economic crisis method of Bolton et al. (2013) into consideration; the authors also use the relative market condition to illustrate the motivation and market timing of cross-border M & A in this paper to connected the bidders’ markets and targets’ markets together to build the general explaining model for cross-border M & A.

By analyzing the new model the authors build in this paper, the authors get three conclusions. Conclusion 1: when the bidders’ technologies are more advanced than the targets’, the bidders prefer market-seeking cross-border M & A, and the relatively higher the bidders’ technologies are, the stronger the preference is; when the bidders’ technologies are less advanced than the targets’, the bidders prefer technology-seeking cross-border M & A, and there exists an optimal relative technology ratio at which the bidders have the strongest motivation to exercise the technology-seeking type cross-border M & A. Conclusion 2: host country’s high economic growth helps attracting market-seeking cross-border M & A, conversely host country’s low economic growth helps attracting technology-seeking cross-border M & A. Conclusion 3: the bidders prefer to exercise the technology-seeking cross-border M & A when the home markets are stable or when economic crises happen in targets markets; and the bidders prefer not to exercise the market-seeking cross-border M & A when economic crises happen in home markets; and the relationship between the motivation for bidders to exercise market-seeking cross-border M & A and the possibility of the happening of economic crisis in home countries presents an inverse N-shape curve.

In this paper the authors first use the relative market condition to illustrate the motivation and market timing in the cross-border M & A research area and build a general model based on current literatures.

The purpose of this paper is to establish a two-stage grey cloud clustering model under the panel data for the multi-attribute clustering problem with three-parameter interval grey number to evaluation of agricultural drought resistance grade of 18 cities in Henan Province.

The clustering process is divided into two stages. In the first stage: Combining variance and time degree, the time weight optimization model is established. Applying the prospect theory, the index weight optimization model is established. Then, with the help of grey possibility function, the first stage of grey cloud clustering evaluation is carried out. In the second stage: the weight vector group of kernel clustering is constructed, and the grey class of the object is determined. A two-stage grey cloud clustering model under the panel data for the multi-attribute clustering problem is proposed.

This paper indicates that 18 cities in Henan Province are divided into four categories. The drought capacity in Henan province is high in the east and low in the west, high in the south and low in the north and the central region is relatively stable. The drought is greatly affected by natural factors. And the rationality and validity of this model is illustrated by comparing with other methods.

This paper provides a practical method for drought resistance assessment, and provides theoretical support for farmers to grasp the drought information timely and improve the drought resistance ability.

The model in this paper solves the situation of ambiguity and randomness to some extent with the help of grey cloud possibility function. Moreover, the time weight of time degree and variance are used to reduce the volatility and the degree of subjective empowerment. Considering the risk attitude of the decision makers, the prospect theory is applied to make the index weight more objective. The rationality and validity of the model are illustrated by taking 18 cities in Henan Province as examples.

The purpose of this study is to reveal the friction reduction performance and mechanism of granular flow lubrication during the milling of difficult-to-machining materials and provide a high-performance lubrication method for the precision cutting of nickel-based alloys.

The milling tests for Inconel 718 superalloy under dry cutting, flood lubrication and granular flow lubrication were carried out, and the milling force and machined surface quality were used to evaluate their friction reduction effect. Furthermore, based on the energy dispersive spectrometer (EDS) spectrums and the topographical features of machined surface, the lubrication mechanism of different granular mediums was explored during granular flow lubrication.

Compared with flood lubrication, the granular flow lubrication had a significant force reduction effect, and the maximum milling force was reduced by about 30%. At the same time, the granular flow lubrication was more conducive to reducing the tool trace size, repressing surface damage and thus achieving better surface quality. The soft particles had better friction reduction performance than the hard particles with the same particle size, and the friction reduction performance of nanoscale hard particles was superior to that of microscale hard particles. The friction reduction mechanism of MoS₂ and WS₂ soft particles is the mending effect and adsorption film effect, whereas that of SiO₂ and Al₂O₃ hard particles is mainly manifested as the rolling and polishing effect.

Granular flow lubrication was applied in the precision milling of Inconel 718 superalloy, and a comparative study was conducted on the friction reduction performance of soft particles (MoS₂, WS₂) and hard particles (SiO₂, Al₂O₃). Based on the EDS spectrums and topographical features of machined surface, the friction reduction mechanism of soft and hard particles was explored.

Charitable giving in China has moved from being subjected to government attention and public skepticism to receiving government encouragement and public support. The role played by political connections in philanthropy is indisputable, although very few studies have explored their association from the perspective of the country’s first Charity Law of 2016. This study aims to contribute to the ongoing debate about the 2016 Charity Law and offers an understanding of the future trends in corporate charitable giving.

Using empirical analysis of data collected from listed companies in China, this study analyzes the impact of political connections on corporate charitable giving before and after the 2016 Charity Law. The study adopts three leading theories from previous research into corporate charitable giving and political connections: corporate social responsibility, resource dependence theory and stakeholder theory. A conceptual framework is outlined, and hypotheses are formulated accordingly.

The results show that political connections have a substantial positive impact on corporate charitable giving, both before and after the implementation of the 2016 Charity Law, which has significantly promoted and increased the amount and proportion of charitable giving. Although the 2016 Charity Law attempted to weaken the political connections of enterprises, the influence of political connections on corporate charitable giving has proved difficult to diminish or eliminate, as charity is dominated by the state.

This study explores the association between political connections and corporate charitable giving from the perspective of China’s Charity Law of 2016.