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The purpose of this study is to investigate the effects of nanoadditive lubricants on the vibration and noise characteristics of helical gears compared with conventional lubricants. The experiment aims to analyze whether nanoadditive lubricants can effectively reduce gear vibration and noise under different speeds and loads. It also analyzes the sensitivity of the vibration reduction to load and speed changes. In addition, it compares the axial and radial vibration reduction effects. The goal is to explore the application of nanolubricants for vibration damping and noise reduction in gear transmissions. The results provide a basis for further research on nanolubricant effects under high-speed conditions.

Helical gears of 20CrMnTi were lubricated with conventional oil and nanoadditive oils. An open helical gearbox with spray lubrication was tested under different speeds (200–500 rpm) and loads (20–100 N·m). Gear noise was measured by a sound level meter. Axial and radial vibrations were detected using an M+P VibRunner system and fast Fourier transform analysis. Vibration spectrums under conventional and nanolubrication were compared. Gear tooth surfaces were observed after testing. The experiment aimed to analyze the noise and vibration reduction effects of nanoadditive lubricants on helical gears and the sensitivity to load and speed.

The key findings are that nanoadditive lubricants significantly reduce the axial and radial vibrations of helical gears under low-speed conditions compared with conventional lubricants, with a more pronounced effect on axial vibrations. The vibration reduction is more sensitive to rotational speed than load. At the same load and speed, nanolubrication reduces noise by 2%–5% versus conventional lubrication. Nanoparticles change the friction from sliding to rolling and compensate for meshing errors, leading to smoother vibrations. The nanolubricants alter the gear tooth surfaces and optimize the microtopography. The results provide a basis for exploring nanolubricant effects under high speeds.

The originality and value of this work is the experimental analysis of the effects of nanoadditive lubricants on the vibration and noise characteristics of hard tooth surface helical gears, which has rarely been studied before. The comparative results under different speeds and loads provide new insights into the vibration damping capabilities of nanolubricants in gear transmissions. The findings reveal the higher sensitivity to rotational speed versus load and the differences in axial and radial vibration reduction. The exploration of nanolubricant effects on gear tribological performance and surface interactions provides a valuable reference for further research, especially under higher speed conditions closer to real applications.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-07-2023-0220/

The purpose of this paper is to evaluate an English Proficiency (EP) programme and its efficacy with respect to students' academic performance in a university within a multi-lingual context, as the programme had been in effect for some years.

A quasi-experimental approach was used to study the efficacy of an EP programme in a university within a multilingual context. Data across two academic years were used, along with regression discontinuity design.

Results suggest that the EP programme had a significant and positive intervention effect on students' initial semester grade point average. The programme effect size was found to be medium to large.

It might be useful to extend the study for one more year for more concrete conclusions. As the study was anchored upon the structure of the 2016 EP programme, any major curricular/structural change to the programme warrants another study.

This study demonstrated that the implementation of EP programmes in higher education institutions is essential not only for international students who are foreign language speakers of English but also for domestic students in English-speaking countries, especially for bi/multilingual speakers.

Previous studies related to the efficacy of EP within higher education have focused on international students who speak English as an additional/foreign language. Further, most studies have focussed on students' self-reported experiences and have yielded disparate findings. This study contributes to scholarship as it addresses the under-researched area related to domestic students who speak English as the first language in a bi/multi-lingual context.

The purpose of this paper is to separate and purify flavonoids from glycyrrhiza by macroporous adsorption resin (MAR) mixed-bed technology.

The adsorption performance of MAR and MAR mixed bed for flavonoids was studied using ultraviolet-visible spectrophotometry.

The research shows that the MAR mixed bed of LZ-50+LZ-59 with a mass ratio of LZ-50:LZ-59(m:m) = 1:1 was the optimized combination with the optimal conditions of adsorption (pH = 6, T = 45°C) and desorption (liquid ratio R = 70%, T = 50°C, pH = 8) obtained, relatively.

This paper provides a novel way to separate flavonoids from glycyrrhiza. Under the optimal conditions, the adsorption rate (F) of MAR mixed-bed LZ-50+LZ-59 to the flavonoids was 62.5 per cent/g, the desorption rate (D) was 89.23 per cent and the purity was achieved at 80 per cent.

The purpose of this paper is to examine the effect of New Rural Pension Scheme (NRPS) on the private transfer behavior of the non-co-resident adult children to their elderly parents in rural China, and hence address the income redistribution effectiveness of public program for the elderly in rural China.

Pooled data from two waves of the China Health and Retirement Longitudinal Study and the combination of regression discontinuity design and difference in difference method are used to perform the analysis.

No evidence is found that pension payment from NRPS program does significantly crowd out the economic support from the adult children to their elder parents. The heterogeneous effects at different income percentile indicate that pension payment significantly increases the probability of receiving gross transfers and likelihood of the net transfer being positive for those elderly individuals with low income; in particular, the distinctive “family binding” arrangement may dramatically contribute to increasing the probability of receiving private transfers for the pension recipients.

The empirical findings would have far-reaching implications for the efficacy of public transfer or re-distributive programs such as NRPS; for the rural elderly, in particular, the unique “family binding” mechanism under the NRPS program may have positive welfare effects on the intended beneficiaries. Furthermore, an understanding of the inter-linkage between informal arrangements of elderly support and social re-distributive program provides further insight into the design of social security systems targeted to the vulnerable group in developing countries.

The purpose of this paper is to study the dynamic transmission of the oil film in soft start process of hydro-viscous drive (HVD) between the friction pairs with consideration of surface roughness, and obtain the distribution law of temperature, velocity, pressure, shear stress and viscous torque of the oil film.

The revised soft-start models of HVD were derived and calculated, including average Reynolds equation, asperity contact model, load force model and total torque model. Meanwhile, a 2D model of the oil film between friction pair was built and solved numerically using computational fluid dynamics (CFD) technique in FLUENT.

The results show that the maximum temperature gradually reduces from the intermediate range (z = 0.5 h) to the inner side of the friction pair along the direction of oil film thickness. As the soft-start process continues, pressure gradient along the direction of the oil film thickness gradually changes to zero. In addition, tangential velocity increases and yet radial velocity decreases with the increase of the radius.

In this paper, it was found that the viscous torque calculated by the numerical method is smaller than that by the CFD model, but their overall trend is almost the same. This also demonstrates the effectiveness of the numerical simulation.

In order to investigate the vibration reduction properties of a three-dimensional elastic metastructure with spherical cavities at low frequencies.

The bandgap characteristics of a three-dimensional elastic metastructure with spherical cavities are studied based on analytical and numerical approaches.

The results of both method revealed that the vibration of the vertexes masses is important for opening bandgaps. The fact that the big sphere cavity radius or short side length of the cube unit leads to a wider bandgap, is noteworthy.

This research provides theoretical guidance for realizing the vibration attenuation application of EMs in practical engineering.

The purpose of this study is to evaluate the impact of environmental uncertainty on corporate social responsibility (CSR), and involves corporate financial investment as mediating factor into this relationship to identify whether Chinese enterprises pursue fame or profit under rising environmental uncertainty.

Data of listed companies in China from 2010 to 2019 are employed. Fixed effect and mediating effect models were used to explore the relationship between environmental uncertainty, corporate financial investment, and CSR. The heterogeneity influence and moderating effect are discussed by using the method of grouping test and adding interactive items.

The study finds that rising environmental uncertainty has a negative impact on CSR. It stimulates managements' short-sighted motivation, so that enterprises prioritize financial investment that can solve short-term goals, rather than CSR performance. This inhibitory effect is caused by holding illiquid financial assets with the motivation of “speculative profit seeking.” The negative effect is greater in the samples of state-owned enterprises, nonfamily enterprises and enterprises with low risk-taking.

It provides a decision-making direction for implementation of CSR governance and the construction of CSR system, particularly in emerging market economies.

CSR is widely known in developed countries for its formation, development and role, but its effectiveness and behavioral motivation are less mentioned in emerging markets. In the future, the research in this area needs to be further advanced.

The study makes significant contributions to the mechanisms behind the link between environmental uncertainty and CSR by taking corporate financial investment as an intermediary factor into the analysis, especially in the unique market context of China.

The main aim of this study was to examine the earnings management behaviours, including both accrual-based and cash flow-based earnings management, of Chinese firms during the Global Financial Crisis (GFC).

A data set of 1,392 firm-year observations derived from a large sample of China's top listed firms (based on total assets) was constructed and investigated via univariate and ordinary least squares regression analyses.

Two distinct conclusions can be drawn from the results of the study. First, the top Chinese listed firms did engage in earnings management, as indicated by comparisons of the means of the absolute values of both accrual-based and cash flow-based earnings management indicators in the periods before and after 2008 when the GFC started. Second, investigation of earnings management directions revealed that in response to the GFC, the firms from construction-related industries and the airline industry manipulated earnings upwards through either accrual-based and/or cash flow-based earnings management activities. On the other hand, firms in the household durables industry engaged in earnings-reducing activities. These findings reflect the effect of the stimulus package launched by the Chinese Government in an effort to combat the GFC. In addition, the results indicate that firm characteristics such as size, leverage, profitability and growth affected the earnings management behaviours of the firms analysed in the study.

The empirically derived findings of this study contribute to the literature pertaining to the effects of the GFC on earnings management practices in China, which has remained relatively scant to date.

The purpose of this paper is to explore the impact of ChatGPT on the development of corporate social responsibility (CSR).

Based on the current applications of ChatGPT in enterprises and existing challenges in CSR, the paper analyzes how the tool promotes corporate sustainable development and what potential risks and challenges are in the practical application.

This paper finds that ChatGPT can promote the development of CSR from four aspects: to support social responsibility activities, to strengthen internal control, to promote external supervision and to convey the notion of sustainability and other corporate philosophies for enterprises.

This paper provides the ground for applying ChatGPT to CSR and includes the potential risks and challenges of the practical applications that enterprises can use for reference.

ChatGPT is becoming increasingly popular and mature, but its applications and effectiveness are less mentioned in CSR. In the future, the research in this area needs to be further advanced.

This paper makes contributions to the link between ChatGPT and CSR. To the best of the authors’ knowledge, this is one of the first studies that explore the applications, impacts, challenges and opportunities of the technology in the area of social responsibility.

The behavioral decision-making of digital-self is one of the important research contents of the network of crowd intelligence. The factors and mechanisms that affect decision-making have attracted the attention of many researchers. Among the factors that influence decision-making, the mind of digital-self plays an important role. Exploring the influence mechanism of digital-selfs’ mind on decision-making is helpful to understand the behaviors of the crowd intelligence network and improve the transaction efficiency in the network of CrowdIntell.

In this paper, the authors use behavioral pattern perception layer, multi-aspect perception layer and memory network enhancement layer to adaptively explore the mind of a digital-self and generate the mental representation of a digital-self from three aspects including external behavior, multi-aspect factors of the mind and memory units. The authors use the mental representations to assist behavioral decision-making.

The evaluation in real-world open data sets shows that the proposed method can model the mind and verify the influence of the mind on the behavioral decisions, and its performance is better than the universal baseline methods for modeling user interest.

In general, the authors use the behaviors of the digital-self to mine and explore its mind, which is used to assist the digital-self to make decisions and promote the transaction in the network of CrowdIntell. This work is one of the early attempts, which uses neural networks to model the mental representation of digital-self.