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This study aims to analyse the deep resource mining that causes high in situ stress, and the disturbance of tunnelling and mining which may induce large stress concentration, plastic deformation and rock strata compression deformation. The depth of deep resources, excavation rate and multilayered heterogeneity are critical factors of excavation disturbance in deep rock. However, at present, there are few engineering practices used in deep resource mining, and it is difficult to analyse the high in situ stress and dynamic three-dimensional (3D) excavation process in laboratory experiments. As a result, an understanding of the behaviours and mechanisms of the dynamic evolution of the stress field and plastic zone in deep tunnelling and mining surrounding rock is still lacking.

This study introduced a 3D engineering-scale finite element model and analysed the scheme involved the elastoplastic constitutive and element deletion techniques, while considering the influence of the deep rock mass of the roadway excavation, coal seam mining-induced stress, plastic zone in the process of mining disturbance of the in situ stress state, excavation rate and layered rock mass properties at the depths of 500 m, 1,500 m and 2,500 m of several typical coal seams, and the tunnelling and excavation rates of 0.5 m/step, 1 m/step and 2 m/step. An engineering-scale numerical model of the layered rock and soil body in an actual mining area were also established.

The simulation results of the surrounding rock stress field, dynamic evolution and maximum value change of the plastic zone, large deformation and settlement of the layered rock mass are obtained. The numerical results indicate that the process of mining can be accelerated with the increase in the tunnelling and excavation rate, but the vertical concentrated stress induced by the surrounding rock intensifies with the increase in the excavation rate, which becomes a crucial factor affecting the instability of the surrounding rock. The deep rock mass is in the high in situ stress state, and the stress and plastic strain maxima of the surrounding rock induced by the tunnelling and mining processes increase sharply with the excavation depth. In ultra-deep conditions (depth of 2,500 m), the maximum vertical stress is quickly reached by the conventional tunnelling and mining process. Compared with the deep homogeneous rock mass model, the multilayered heterogeneous rock mass produces higher mining-induced stress and plastic strain in each layer during the entire process of tunnelling and mining, and each layer presents a squeeze and dislocation deformation.

The results of this study can provide a valuable reference for the dynamic evolution of stress and plastic deformation in roadway tunnelling and coal seam mining to investigate the mechanisms of in situ stress at typical depths, excavation rates, stress concentrations, plastic deformations and compression behaviours of multilayered heterogeneity.

The purpose of this study was the preparation of a poly(styrene-co-maleic anhydride)-g-polyetheramine (SMA-g-PEA) hyperdispersant that reduces the viscosity of the system and improves the colouring intensities of pigments.

PEA of specific quality was dissolved in propylene glycol methyl ether. SMA was then added according to the required mass ratio. The solution was refluxed for 10 h under a stream of protective N2. The prepared hyperdispersant was then characterised by Fourier-transform infrared, UV–visible and ¹H NMR spectroscopies, gel-permeation chromatography and thermogravimetry.

PEA was successfully grafted onto the SMA polymer and the synthesised product was found to be thermally stable. The copolymer with a 6:1 mass ratio is the best dispersant and was used to disperse carbon black, phthalocyanine blue and permanent violet in water-based systems, which helps to improve the application performance of each pigment by reducing the viscosity of the system and improving the colouring intensity of the pigment. The water dispersion is stable and does not exhibit an increase in viscosity after seven days of oven aging at 50°C.

SMA-g-PEA water-based hyperdispersants were successfully synthesised. The prepared hyperdispersants help to improve the application performance of each studied pigment by reducing the viscosity of the system and improving the colouring intensity of the pigment.

Using data from the China Health and Nutrition Survey, this work examines the relationship between housing price and the probability of marriage among the young.

By exploiting land reform as an exogenous change in housing price and employing a differences-in-differences framework, this study investigates the effects of housing price on the marriage probability of young people.

This work confirms that land reform decreased young people's likelihood of marriage. This finding is robust to a series of model specifications. The effects of land reform increased over time because of rising housing unaffordability from progressively inflating housing prices. Moreover, land reform had larger effects on renters and young adults aged below 30 than homeowners and young adults aged above 30.

Overall, this study highlights the negative consequences of an overheated housing market on marriage in developing countries.

Housing prices have increased dramatically in urban China after 2002 upon the implementation of the assignment system of the use right of all kinds of profit-oriented lands by means of public bidding, auction and quotation. High housing prices indicate serious housing unaffordability, especially for young people who typically have low income and wealth. Homeownership that comes with various benefits can theoretically increase the likelihood of marriage, particularly in China where a house is often regarded as a prerequisite for marriage.

Clothing comfort has been one important and complex area which is the result of a balanced process of heat and moisture/liquid exchange between the human body, the clothing system and the environment. And the clothes will represent different properties when they are in different conditions, which have great influence on human comfort. Therefore, the purpose of this paper is to investigate the hygroscopicity-exothermicity property of plain cotton fabric.

A real-time testing device for monitoring the temperature change of cotton fabrics after adsorbing liquids was constructed, and serveral liuqids such as water, NaCl solution with different concentrations, NaOH solution with different concentrations, and urea solution with different concentrations were used in this work.

It was found out that absorption of liquids by cotton fabric was followed by the liberation of heat, which increased the temperature of cotton fabric as well as the temperature of surrounding environment, and the process of temperature increase was much shorter than the process of temperature decrease. In addition, the released heat energy were different according to different liquids as well as the concentrations of liquid solutions.

There have some studies in the heat of water/vapor sorption of textiles. Here the temperature changes of surrounding environment and fabric after absorbing different liquids were real-time observed and recorded.

The modernization of China’s economy is an integral part of Chinese-style modernization. According to the principle of unifying theoretical, historical and practical logic, theoretically explaining the modernization of China’s economy is both a political necessity and a higher scientific requirement.

Following this evolutionary line – from modes of production to the general economic development mechanism and then to patterns of economic operation and development – this paper employs the principal contradiction analysis method to offer an interpretation of China’s economic modernization from the broad Marxist political economy perspective.

In economic terms, “get organized” primarily refers to the development and mutual promotion of team-based and market-based division of labor organizations, as discussed by Karl Marx. “Get organized” (specifically the development of team-based division of labor organizations) acts as the engine of China’s economic modernization and serves as the historical logical starting point. Division of labor is the theoretical logical starting point for interpreting China’s economic modernization. The two of them are congruent, achieving the unity of theoretical and historical logic at the starting point. The development and mutual promotion of these “two types of division of labor” inherently generate the general mechanism of economic development first comprehensively discussed by Marx and Friedrich Engels, which involves the division of labor development and market expansion accumulating cyclically and reinforcing each other. This mechanism drives both the high-speed and high-quality development of China’s economic modernization.

The broad Marxist political economy paradigm facilitates explaining China’s economic modernization theoretically, historically and practically with unified logic. “Get organized” serves as both the engine and the realization mechanism of this modernization, with the Communist Party of China (CPC) consistently being the core force of this organizational effort.

This study aims to investigate the effect of countersunk rivet head dimensions on the fatigue performance of the riveted specimens of 2024-T3 alloy.

The relationship between rivet head dimensions and fatigue behavior was investigated by finite element method and fatigue test. The fatigue fracture of the specimens was analyzed by scanning electron microscopy.

A change of the rivet head dimensions will cause a change in the stress concentration and residual normal stress, the stress concentration near the rivet hole causes the fatigue crack source to be located on the straight section of the countersunk rivet hole and the residual normal stress can effectively restrain the initiation and expansion of fatigue cracks. The fatigue cycle will cause the rivet holes to produce different degrees of surface wear.

The fatigue life of the specimens with the height of the rivet head of 2.28 mm and 2.00 mm are similar, but the specimens with the height of the rivet head of 1.72 mm were far higher than the other specimens.

The application of air-jet nozzle in ring spinning system has been turned up in the last decade, and the greatest advantage reported is the reducing of hairiness. In this paper, an attempt has been made to optimize the utility of a single air-jet nozzle in ring spinning system. Some parameters, such as air pressure, the distance between front roller nip line and air-jet nozzle inlet, and the number of orifices were adjusted to get a better quality yarn. In order to confirm the role of these parameters, the properties of ring and jet-ring spun yarns were compared. All the samples were characterized in terms of count, twist, irregularity, hairiness and strength. The results showed that the properties of yarns were improved significantly by setting suitable parameters, but not all of the parameters were significant in each performance index of yarns.

The missing employee voice has become a salient topic in China. This paper aims to document the newest developments relating to the topic by reviewing the recent literature on employment relations and employee voice. The findings of this paper suggest that the purposes of and channels for the employee voice in China have been undergoing significant changes. Different stakeholder groups have approached the issue. ‘Democratic management’ in China, the country’s home-grown concept of employee voice, has been resurrected to encourage more effective employee representation. Apart from this top-down influence from the government and All-China Federation of Trade Unions, this paper also identifies the bottom-up approach driven by the workers, and the external influence from the global corporate social responsibility campaign and nongovernmental labour organizations. Based on the review of the newest developments in workplace democracy and the employee voice in China, this paper proposes a stakeholder framework incorporating these developments. The authors also suggest some directions for future research.

There is widespread debate about the nationalistic top-down approach of citizenship education. By using the notion of cultural citizenship as a useful theoretical lens, citizenship education research tends to focus on the process of subjectivity construction among students’ citizenship learning process. The Communist Party of China plays a dominant role in cultivating citizens in the form of ideological and political education (IaPE) in Chinese universities. The research problem thus focuses on the dynamics and complexity of how Chinese university students construct their subjectivities regarding citizenship learning through IaPE. The main purpose of the study is to provide some research directions for understanding students’ citizenship learning today.

With the case study of one university in China and interview data from 25 students, this paper examines the ways in which students understand and respond to dominant discourses.

The findings revealed there is a deficit of citizenship learning in IaPE, and students felt ideologically pressurized. This study suggests students’ complex subjectivities of active participants but confused minds as a phenomenon in Chinese higher education, in which they must involve in IaPE for personal academic and career development, while they adopted covert strategies for self-conscious citizenship learning expectations. These strategies took the form ranging from obediently completing basic curriculum requirements and distancing away by studying abroad, to actively searching for learning opportunities from other courses and media society.

This paper contributes to citizenship education research by recognizing the complexities of how subjectivities are formed in formal university settings.

China's economic transition is essentially the process of China's institutional changes. During the changes, the appearance of institutional innovation is not regular; instead, it is intermittent and random. The purpose of this paper is to show that the fitful appearance of institutional innovation is the root of China's economic growth and fluctuations.

This paper constructs a real business cycle (RBC) model introducing the institutional factor expressed in the quantitative form under the dynamic stochastic general equilibrium (DSGE) framework by measuring China's institutional changes quantitatively.

By comparing the characteristics of the actual economic data with those of the simulated economic data, we find that this RBC model can explain 94.44%, 66.07%, 23.46%, 21.03% and 15.45% of the cyclical fluctuations in output, investment, labor, consumption and capital, respectively.

The impulse response analysis finds that the institutional shocks have a relatively long duration, lasting about 30 years, and decline slowly over time, while technological shocks decline relatively fast, lasting approximately ten years.