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This paper aims to propose a new ultrasonic diagnosis method for stainless steel weld defects based on multi-domain feature fusion to solve two problems in the ultrasonic diagnosis of austenitic stainless steel weld defects. These are insufficient feature extraction and subjective dependence of diagnosis model parameters.

To express the richness of the one-dimensional (1D) signal information, the 1D ultrasonic testing signal was derived to the two-dimensional (2D) time-frequency domain. Multi-scale depthwise separable convolution was also designed to optimize the MobileNetV3 network to obtain deep convolution feature information under different receptive fields. At the same time, the time/frequent-domain feature extraction of the defect signals was carried out based on statistical analysis. The defect sensitive features were screened out through visual analysis, and the defect feature set was constructed by cascading fusion with deep convolution feature information. To improve the adaptability and generalization of the diagnostic model, the authors designed and carried out research on the hyperparameter self-optimization of the diagnostic model based on the sparrow search strategy and constructed the optimal hyperparameter combination of the model. Finally, the performance of the ultrasonic diagnosis of stainless steel weld defects was improved comprehensively through the multi-domain feature characterization model of the defect data and diagnosis optimization model.

The experimental results show that the diagnostic accuracy of the lightweight diagnosis model constructed in this paper can reach 96.55% for the five types of stainless steel weld defects, including cracks, porosity, inclusion, lack of fusion and incomplete penetration. These can meet the needs of practical engineering applications.

This method provides a theoretical basis and technical reference for developing and applying intelligent, efficient and accurate ultrasonic defect diagnosis technology.

The purpose of this study is to investigate the effect of ferrite on hydrogen embrittlement (HE) of the 17-4PH stainless steels.

The effects of ferrite on HE of the 17-4PH stainless steels were investigated by observing microstructure and conducting slow-strain-rate tensile tests and hydrogen permeability tests.

The microstructure of the ferrite-bearing sample is lath martensite and banded ferrite, and the ferrite-free sample is lath martensite. After hydrogen charging, the plasticity of the two steels is significantly reduced, along with the tensile strength of the ferrite-free sample. The HE susceptibility of the ferrite-bearing sample is significantly lower than the ferrite-free steel, and the primary fracture modes gradually evolved from typical dimple to quasi-cleavage and intergranular cracking. After aging at 480°C for 4 h and hydrogen charging for 12 h, the 40.9% HE susceptibility of ferrite-bearing samples was the lowest. In addition, the hydrogen permeation tests show that ferrite is a fast diffusion channel for hydrogen, and the ferrite-bearing samples have higher effective hydrogen diffusivity and lower hydrogen concentration.

There are a few studies of the ferrite effect on the HE properties of martensitic precipitation hardening stainless steel.

The purpose of this paper is to develop pansystems‐styled traffics, logistics and knowledge rediscovery. The core logoi are the generalized resources//F* and their circulation//C*. The research presents a new outlook to mathematics, physics, traffic, communication, logistics, KD, internet, computer, translation, simulation, information, life‐systems, logic or reasoning, memory or storage, process, transaction, finance, education, inherent, topology, evolution, etc. and then certain mechanism among them and related mutuality can be unveiled.

A flexible combination of philosophy, mathematics and technology is embodied. The paper is an application of pansystems methodology to approach the following topics: pansystems resource, circulation: traffics, logistics and KD; pansystems variational principle and pan‐circulation; pansystems logistics; pansystems network, supply chain and bullwhip effect; pansystems innovation and knowledge rediscovery.

All of the topics concerned are reduced to the actualization of pansystems variational OR and classification‐repetition‐PanOR, which possess a transfield nature.

This paper provides the framework and concretion principles of pansystems research on traffics, logistics, supply chain, bullwhip effect, innovation and related applications, and presents a new world outlook, which leads to some new comprehension to KD and WHF* <world*history*future*>, SEM* <society* economy*management*>.

The purpose of this paper is to improve the generation efficiency of singlet oxygen of methylene blue molecules through finely controlling their aggregation states in drug carriers.

As a photosensitiser in photodynamic therapy, methylene blue (MB) was loaded on citrate-modified hydroxyapatite (HAp) through an electrostatic interaction and followed by encapsulation of coordination complexes of tannic acid (TA) and Fe(III) ions. Ultraviolet-visible absorption spectrum of the supernatant after incubation of samples was recorded at certain time interval to investigate the release behaviour of MB. Photodynamic activity of MB was determined by the oxidation reaction of uric acid by singlet oxygen generated by MB under illumination.

Almost all MB molecules were immediately released from HAp-MB, whilst an initial burst release of MB from HAp-MB@TA was followed by a sustainable and pH-sensitised release. In comparison with HAp-MB, photocatalystic reduction of HAp-MB@TA by titanium dioxide hardly occurred under illumination, indicating the stability against reduction to leukomethylene blue in vitro. Generation efficiency of singlet oxygen by MB released from HAp-MB@TA was significantly higher than that from HAp-MB because of the control of TA and Fe(III) ions complexes on molecular structures of released MB.

A facile method was herein demonstrated to optimise the generation efficiency of singlet oxygen by controlling aggregation states of PS molecules and improve PDT efficiency to damage tumour tissues.

This paper aims to explore the impact of business environment on high-quality economic development (HQED) and clarify the role of technological innovation and government intervention in this relationship.

Based on China’s provincial panel data from 2010 to 2019, this paper adopts the system generalized method of moments to empirically analyze the influential mechanism and heterogeneity of the business environment on HQED. Furthermore, the authors construct a dynamic panel threshold model to test the threshold effect of government intervention.

The results indicate that optimizing the business environment can significantly promote HQED, technological innovation plays a partial mediating role in the impact of business environment on HQED, mainly by enhancing the intensity of innovation input and increasing innovation output to facilitate HQED. Government intervention can regulate the impact of business environment on HQED, and there is a double threshold effect, and it possesses an inverted U-shaped feature of first promoting and then inhibiting.

This paper examines the influence path of business environment on HQED from the perspective of technological innovation and government intervention, filling the gap in the study of provincial business environment. Moreover, the conclusions furnish a theoretical basis for optimizing the business environment and facilitating the HQED in China.

This study aims to examine whether corporate stconcerns on social responsibility issues pressurize corporate managers to act in a socially responsible way and how this affects corporate value.

This study follows previous studies such as Wu et al. (2008) and Jiang and Huang (2011) in using the research model.

The analysis shows that in regions where large attention paid to demolitions, corporate managers are under great pressure from corporate stakeholders and they thus act in more socially responsible ways; this, in turn, results in higher corporate values. Furthermore, in regions in which demolition events attract more attention, the increase in corporate value is relatively small for state-owned enterprises and unprofitable listed enterprises.

The findings demonstrate that internet governance heightens corporate stakeholders’ awareness of social responsibility, and this leads to pressure on corporate relative behaviors to satisfy the requests of corporate stakeholders, leading to an increase in corporate value and improvement in social welfare.

The purpose of this paper is to provide a comprehensive review and critique of what we already know about pay systems in Chinese state‐owned enterprises, to identify the gaps in the literature and to stimulate more research in this area.

The paper first describes the policy issues at the macro‐level (government policies) in order to put micro‐level pay practices in a pertinent context. Then the paper provides a detailed review and critique on current empirical studies on pay practices in Chinese enterprises, their antecedents and consequences. Finally, the paper identifies potential research questions and provides some directions for future research.

The paper concludes from the extensive review of the current literature that the following research areas merit attention: Why do some firms pay their employees more than other firms? Why do we observe different types of internal pay structures among firms? What are the consequences of these different structures? Why is the link between pay and performance weak in some firms but strong in others? Under what conditions pay‐for‐performance enhances firm performance?

The paper is one of the most comprehensive reviews of the literature on compensation practices of Chinese companies.

The purpose of this paper is to explain theoretically the relation between large shareholders, legal institutions, and capital structure, then empirically deduce how large shareholders and legal institution affected capital structure decision by integrating Chinese institutions.

This paper adopted cross‐section data of non‐financial listed companies in China and applied series of ordinary least square to empirically test the relationship between large shareholders, legal institution, and capital structure decision.

The empirical evidence provided by this paper indicates that large shareholders and legal institution do affect capital structure decision, specifically in seven areas.

This paper, based on the institutions of China, takes the largest shareholder, ultimately the controller, the relation of legal institution and capital structure into the research framework for the first time and systematically studies how the capital structure decision making is affected by the controlling shareholders, the nature of ultimately controllers, the concentration degree of shares held by a few large shareholders and legal institution. It is the first to empirically test whether the concentration degree of shares held by a few large shareholders and legal institution will affect the relation between controlling shareholders and capital structure, and compensates for the deficiencies in previous studies.

The purpose of this paper is to examine the relationship between Chinese female executives and corporate risk-taking the contingencies that affect this relationship.

A integrated theoretical framework was established, on the basis of which theoretical hypotheses were developed and tested using 20,315 firm-year observations collected from China’s publicly listed companies during the period 2005–2020. Data were collected from China's Shanghai and Shenzhen A-share Stock Exchanges and analyzed using a moderated regression analysis, PSM, 2SLS-IV and PSM-DID model.

The empirical results indicate a negative effect of the ratio of female executives in top management team on corporate risk-taking, and this negative effect can be weakened by the social capital of board directors and the regional marketization.

The paper contributes to research on the relationship between female executives and risk-taking by considering the effect of eastern culture on female executives’ business decision-making and examining the moderating factors inside and outside the firm.

The paper illustrates the active steps that corporations can take to enhance female executives' willingness and capacity to take firm-related risks so as to improve the firm value in the long run.

The paper explores how Chinese culture and Chinese traditional value affect female executives’ decision-making on risky projects or uncertain investments. In addition, our study for the first time examines the moderating effect of board social capital as an internal factor and marketization as an external one on the relationship between Chinese female executives and corporate risk taking. The research examines the gender inequality in the work and competitive environment facing female executives in the areas of different marketization level, which would affect female executives’ cognition and motivation in corporate risk taking.