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The purpose of this paper was to study the corrosion control of B10 copper-nickel alloy using the LiOH-N₂H₄ compound inhibitors and to evaluate the feasibility of replacing the original inhibitors (NaNO₂-Na₂MoO₄) with the new ones (LiOH-N₂H₄) for the chilled water system in a nuclear unit.

The corrosion resistance performance of B10 copper-nickel alloy was evaluated during the whole replacement process of inhibiters using electrochemical tests and surface analysis techniques.

The results indicated that the corrosion of B10 copper-nickel alloy could be prevented effectively using LiOH to increase the pH value of solution higher than 10.0 and using N₂H₄ to consume dissolved oxygen. During the replacement process of inhibitors from NaNO₂-Na₂MoO₄ to LiOH-N₂H₄, the corrosion resistance performance of B10 copper-nickel alloy had not decreased greatly. The new LiOH-N₂H₄ inhibitor, which could enhance the compactness of rust, was able to reduce the corrosion rate of rusted B10 metal.

It is feasible and operable to replace the NaNO₂-Na₂MoO₄ inhibitors with the LiOH-N₂H₄ inhibitors for the corrosion prevention of B10 copper-nickel alloy. The research results can provide guidelines for the inhibitor selection of chilled water system in a nuclear unit.

The assumption that the family migrates as a unit downplays migrants’ circularity. This chapter focuses on China's rural–urban labor migrants that travel back and forth between the sites of work and home community and between places of work. I argue that migrants and their households pursue work flexibility in order to obtain the best of the urban and rural worlds, by gaining earnings from urban work and at the same time maintaining social and economic security in the countryside. Work flexibility demands flexibility in household organization, in the form of division of labor and collaboration between genders, generations, and households. Based on a study in Sichuan, I examine household biographies and narratives to identify migrants’ work and household strategies.

Migrants change jobs frequently, switch from one type of work to another and one location to another readily, and often return to the home village for months or even years before pursuing migrant work again. Not only are migrants ready to split the household between the city and the countryside, but also they frequently change from one form of division of labor to another. The inside–outside model, where the wife stays in the village and the husband does migrant work, used to be the dominant arrangement. Over time, the outside–outside model, where both the husband and wife migrate to work and leave behind other family members, is increasingly popular. This is facilitated by intergenerational and interhousehold division of labor in the form of assistance by the extended family. Intergenerational division of labor takes place when the second generation is replacing the parents in migrant work. This research's findings support the notion that rural–urban migrants are fast becoming a hybrid segment of Chinese society, playing dual roles of farmers and urban workers and straddling the peasant and urban worlds.

The structure stiffness is greatly affected by the fixture constraints during assembly due to the flexibility of large-scale thin-walled structures. The compliant deformation of structures is usually not consistent for the non-uniform stiffness in various clamping schemes. The purpose of this paper is to investigate the correlation between the assembly quality and the clamping schemes of structures with various initial deviations and geometrical parameters, which is based on the proposed irregular quadrilateral plate element via absolute nodal coordinate formulation (ANCF).

Two typical clamping schemes are specified for the large-scale thin-walled structures. Two typical deviation modes are defined in both free and clamping states in the corresponding clamping schemes. The new irregular quadrilateral plate element via ANCF is validated to analyze the compliant deformation of assembled structures. The quasi-static force equilibrium equations are extended considering the factors of clamping constraints and geometric deviations.

The initial deviations and geometrical parameters strongly affect the assembly deviations of structures in two clamping schemes. The variation tendencies of assembly deviations are demonstrated in details with the circumferential clamping position and axial clamping position in two clamping schemes, providing guidance to optimize the fixture configuration. The assembly quality of structures with deviations can be improved by configuration synthesis of the clamping schemes.

Typical over-constraint clamping schemes and deviation modes in clamping states are defined for large-scale thin-walled structures. The plate element via ANCF is extended to analyze the assembly deviations of thin-walled structures in various clamping schemes. Based on the proposed theoretical model, the effects of clamping schemes and initial deviations on the deformation and assembly deviation propagation of structures are investigated.

A new deviation propagation model considering the form defects in compliant assembly process is proposed. The purpose of this paper is to analyze the deviation propagation by using the basic deviation fields. In particular, each basic deviation field is defined with a generalized compliance matrix of part.

First, the form defects of parts may be decomposed into a linear combination of basic deviation fields, which are constructed by the eigen-decomposition of the structure stiffness of parts with ideal dimensions. Each basic deviation field is defined with a generalized compliance of part. Moreover, by analyzing the relationship between the basic deviation fields before and after assembling process, a new sensitive matrix is obtained in which each value expresses the correlation of a basic deviation field between the parts and the assembly.

This model may solve the deviation propagation problems of compliant assembly with considering form defects. Here, one case is used to illustrate the deviation propagation in the assembly process. The results indicate that the proposed method has higher accuracy than the method of influence coefficient when the entire deviation fields of parts are considered. Moreover, the numerical results with the proposed method basically agree with the experimental measurements.

Owing to the hypothesis of linear superposition of basic deviation fields, the research in this paper is limited to the parts with linear elastic deformation. However, the entire form defects of parts are considered rather than the deviations of the local feature points. It may be extended to analyze the three-dimensional deviations of complex thin-walled parts.

A deviation propagation model considering parts form defects is developed to achieve more accurate predictions of assembly deviation by using the basic deviation fields.

The overload of user-generated content in online mental health community makes the focus and resonance tendencies of the participating groups less clear. Thus, the purpose of this paper is to build an early identification mechanism for users' high attention content to promote early intervention and effective dissemination of professional medical guidance.

We decouple the identification mechanism from two processes: early feature combing and algorithmic model construction. Firstly, based on the differentiated needs and concerns of the participant groups, the multiple features of “information content + source users” are refined. Secondly, a multi-level fusion model is constructed for features processing. Specifically, Bidirectional Encoder Representation from Transformers (BERT)-Bi-directional Long-Short Term Memory (BiLSTM)-Linear are used to refine the semantic features, while Graph Attention Networks (GAT) is used to capture the entity attributes and relation features. Finally, the Convolutional Neural Network (CNN) is used to optimize the multi-level fusion features.

The results show that the ACC of the multi-level fusion model is 84.42%, F1 is 79.43% and R is 76.71%. Compared with other baseline models and single feature elements, the ACC and F1 values are improved to different degrees.

The originality of this paper lies in analyzing multiple features based on early stages and constructing a new multi-level fusion model for processing. Further, the study is valuable for the orientation of psychological patients' needs and early guidance of professional medical care.

Considering the role of analysts in disseminating information, the paper explains the idiosyncratic volatility puzzle of China's stock market. As the largest developing country, China's research can provide meaningful reference for the research of financial markets in other new countries.

From the perspective of behavior, establishing a direct link between individual investor attention and stock price overvaluation.

The authors find that there is a significant idiosyncratic volatility puzzle in China's stock market. Due to the role of mispricing, individual investor attention significantly enhances the idiosyncratic volatility effect, that is, as individual investor attention increases, the greater the idiosyncratic volatility, the lower the expected return. Attention can explain the idiosyncratic volatility puzzle in China's stock market. In addition, due to the role of information production and dissemination, securities analysts can reduce the degree of market information asymmetry and enhance the transparency of market information.

China is the second largest economy in the world, and few scholars analyze it from the perspective of investors' attention. The authors believe this paper has the potential in contributing to the academia.

This paper aims to study the influence of aerodynamics force of trains passing each other on the dynamic response of vehicle bridge coupling system based on numerical simulation and multi-body dynamics and put forward the speed threshold for safe running of train under different crosswind speeds.

The computational fluid dynamics method is adopted to simulate the aerodynamic force in the whole process of train passing each other by using dynamic grid technology. The dynamic model of vehicle-bridge coupling system is established considering the effects of aerodynamic force of train passing each other under crosswind, the dynamic response of train intersection on the bridge under crosswind is computed and the running safety of the train is evaluated.

The aerodynamic force of trains' intersection has little effects on the derailment factor, lateral wheel-rail force and vertical acceleration of train, but it increases the offload factor of train and significantly increases the lateral acceleration of train. The crosswind has a significant effect on increasing the derailment factor, lateral wheel-rail force and offload factor of train. The offload factor of train is the key factor to control the threshold of train speed. The impact of the aerodynamic force of trains' intersection on running safety cannot be ignored. When the extreme values of crosswind wind speed are 15 m·s⁻¹, 20 m·s⁻¹ and 25 m·s⁻¹, respectively, the corresponding speed thresholds for safe running of train are 350 km·h⁻¹, 275 km·h⁻¹ and 200 km·h⁻¹, respectively.

The research can provide a more precise numerical method to study the running safety of high-speed trains under the aerodynamic effect of trains passing each other on bridge in crosswind.

This study aims to investigate the influence of three key categories of perceived entrepreneurial obstacles (perceived loss of financial resources, perceived loss of customer demand and perceived loss of social support) on entrepreneurial behavior tendency through fear of failure and negative emotion to shed light on why Chinese entrepreneurship has fallen into a decline from the individual level.

A sample of 256 Chinese makers who were achieving their innovative ideas in makerspaces was used to test the research model. Then, the structural equation modeling was adopted for data analysis.

The results indicate that fear of failure is the strongest psychological barrier to entrepreneurial behavior tendency and the strongest trigger for negative emotion; both negative emotion and fear of failure are affected by entrepreneurial obstacles of perceived loss of financial resources and perceived loss of social support. However, perceived loss of customer demand is not the inducement for both fear of failure and negative emotion.

This study adopts stressor-strain-outcome framework in studying entrepreneurship to help understand what prevent potential entrepreneurs from stepping into entrepreneurship. In addition, this study offers a new insight into entrepreneurship by emphasizing the decisive impact of inhibitive factors on personal entrepreneurship.

Emerging-market multinational enterprises (EMNEs) can choose focused or ambidextrous strategies to catch up with global market leaders through overseas foreign direct investment (OFDI). The Belt and Road Initiative (BRI), launched by the Chinese government in 2013, had a profound impact on Chinese multinational enterprises’ international behavior. This paper analyses how EMNEs select focused or ambidextrous catch-up strategies before and after the BRI, integrating ambidexterity and catch-up theories to provide a more nuanced understanding of the evolution of EMNE strategy.

A case study is well suited for deriving rich descriptions of empirical phenomena for which little theory exists. Because the existing literature has not yet fully explored and conceptually modeled the influence of windows of opportunity on international catch-up strategies, we use qualitative research to explore the mechanisms of strategy evolution in EMNEs.

The results show that the choice of catch-up strategy is influenced by the nature of windows of opportunity and the firm's accumulated technological capability. Specifically, the opening of institutional windows as a result of the BRI could give significant momentum to the international catch-up process by providing incentives and opportunities for EMNEs to enter more markets and new technology fields. The EMNEs studied underwent a transition from a focused strategy in the catch-up stage to an ambidextrous strategy in the beyond catch-up stage.

These conclusions can not only deepen our understanding of the dynamics of catch-up strategies in the global context but also enrich the research on the ambidexterity of EMNEs, especially in the context of the BRI.

Explains why, following China‘s implementation of a market economy, public accounting firms were required to affiliate (hook‐up) with existing government or educational institutions until 1993 when partnerships and limited liability firms were also allowed. Describes the rules relating to independent accounting firms and changes which should foster their development but reports that, in fact, most firms are still affiliated. Discusses the reasons for this and the resulting problems, e.g. lack of competition and independence, low quality of service and increases in fraud, misrepresentation and under‐disclosure. Reveals that despite the 1995 exposure draft on eliminating the hooking‐up structure few de‐affiliations have taken place and identifies four problems which need solving if full de‐affiliation is to be achieved.