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Whether a fire can be initiated in an explosion accident depends on the explosion and deflagration process. In the methane-air explosion in a tunnel, the flame accelerates from the ignition point. However, where it begins to decelerate is not clear. The purpose of this paper is to examine the explosion overpressure, flow and flame propagation beyond the premixed area of methane-air in a tunnel.

The numerical simulation was used to study the explosion processes of methane-air mixtures in a tunnel. Based on the numerical simulation and its analysis, the explosion overpressure, flow and flame propagation rules beyond the premixed area were demonstrated for a methane-air explosion.

The peak overpressure of methane-air mixture explosion was observed to reach its maximum beyond the original premixed area of methane-air. The hazardous effects beyond the premixed area may be stronger than those within the premixed area for a methane-air explosion in a tunnel. Under the conditions of this study, the ratio between the length of combustion area (40 m) and that of original premixed area (28 m) reaches 1.43.

Little attention has been devoted to investigating the explosion overpressure, flow and flam propagations beyond the original premixed area of methane-air in a tunnel. Based on the numerical simulation and the analysis, the propagation rule of overpressure wave and flow inside and outside the space occupied by methane/air mixture at the volume fraction of 9.5 percent in a tunnel were obtained in this work.

The purpose of this paper is to study propagation characteristics of methane explosion in the pipe network and analyze the propagation laws of methane explosion wave along the elbow pipe and pipe network.

Numerical simulation using software package AutoReaGas, a finite-volume computational code for fluid dynamics suitable for gas explosion and blast problems, is adopted to simulate the propagation characteristics of methane explosion and the property of flow field in complex structures.

Due to reflection effects of corners of elbow pipe, the peak overpressures at corner locations in the elbow pipe go about two times higher than that in the straight pipe. In the parallel pipe network, the peak overpressure increases significantly at the intersection point, while the flame speed decreases at the junction. All these indicate that pipe corners and bifurcations could substantially enhance explosion partly which can bring more severe damage at the corner area. The explosion violence is strengthened after flames and blast waves are superimposed, such that equipments and people in these areas need special strengthening protection.

The numerical results presented in this paper may provide some useful guidance for the design of the underground laneway structures and to take protective measures at corners and bifurcations in coal mines.

Continuous fiber reinforced thermoplastic composites (CFRTPCs) with great mechanical properties and green recyclability have been widely used in aerospace, transportation, sports and leisure products, etc. However, the conventional molding technologies of CFRTPCs, with high cost and low efficiency, limit the property design and broad application of composite materials. The purpose of this paper is to study the effect of the 3D printing process on the integrated rapid manufacturing of CFRTPCs.

Tensile and flexural simulations and tests were performed on CFRTPCs. The effect of key process parameters on mechanical properties and molding qualities was evaluated individually and mutually to optimize the printing process. The micro morphologies of tensile and flexural breakages of the printed CFRTPCs were observed and analyzed to study the failure mechanism.

The results proved that the suitable process parameters for great printing qualities and mechanical properties included the glass hot bed with the microporous and solid glue coatings at 60°C and the nozzle temperature at 295°C. The best parameters of the nozzle temperature, layer thickness, feed rate and printing speed for the best elastic modulus and tensile strength were 285°C, 0.5 mm, 6.5r/min and 500 mm/min, respectively, whereas those for the smallest sectional porosity were 305°C, 0.6 mm, 5.5r/min and 550 mm/min, respectively.

This work promises a significant contribution to the improvement of the printing quality and mechanical properties of 3D printed CFRTPCs parts by the optimization of 3D printing processes.

The purpose of this paper is to purify the wastewater in the garment industry.

The preparation of the calcium alginate (CA)/activated carbon (AC) composite membrane was achieved by vacuum freeze-drying and the cross-linking reaction between sodium alginate and CaCl₂. Effective parameters in the methylene blue (MB) adsorption such as temperature, dose, contact time and pH were discussed. The adsorption properties of the composite membrane were investigated by isotherm, kinetics and thermodynamic analysis. The adsorption equilibrium data were described by the adsorption isotherm Langmuir model and the Freundlich model. The pseudo-first-order, pseudo-second-order and intra-particle diffusion equations were selected to evaluate the kinetics. The thermodynamic study described that the adsorption reaction was spontaneous and exothermic.

The AC/CA membrane is an efficient and powerful adsorbent to remove MB in printing and dyeing wastewater, and provides a new idea for the selection of adsorption materials for industrial printing and dyeing wastewater.

The composite membrane research on CA and AC can provide new ideas for the research of these kinds of materials.

The paper contributes to its wider and convenientapplication in wastewater treatment.

Studies on the combination of CA and AC into adsorption membranes and for the removal of dyes from printing and dyeing wastewater have not been reported. A novel composite material is provided for treatment dyeing wastewater in garment production. The composite membrane research on CA and AC can provide new ideas for the research of these kinds of materials and contribute to its wider and convenient application in wastewater treatment.

This paper aims to explain and resolve the paradoxical situation in China regarding how it is difficult to get an offer of employment in China while people are unwilling to pursue or embark on a career in the Meetings, Incentives, Conventions and Exhibitions (MICE) industry. Therefore, the MICE industry career path should be carefully explored.

The paper used semi-structured interviews with more than 30 representative managers from key MICE companies, a social community perspective and conceptions of the social world combined with the traditional career-ladder model.

The study’s key findings are: a general career path exists in the MICE industry in China; there are three main types of career paths and two different kinds of promotion mechanisms, which vary according to the type of ownership, scale or other characteristics of companies; and a feedback mechanism, linking social-world events and social community characteristics, affects individual employees and their career paths in the MICE industry, leading to promotion in or retreat from the industry. Typically, the mechanism fits high-level employees better than the freshmen, which leads to high turnover in the MICE labor market.

This paper provides a better understanding of MICE industry and facilitates people’s employment choices.

This paper provide a new social community perspective for exploring the MICE career path; there are also significant practical implications for MICE elites, which present a new framework for future research and industry applications.

Leadership.

The case is suitable for MBA, Executive level courses.

Yongye Group is a biotechnological enterprise in Inner Mongolia, China. In China, people lack trust in economic transactions due to the transitional state of the economy, especially regarding food safety. To respond to this situation, Wu Zishen, the chairman of the Board of Directors of Yongye Group, was determined to build trust among employees, distributors, farmers, and consumers towards the company. To this end, he started using a creative incentive system with employees and stakeholders: the pay-before-performance incentive system. According to this system, the reward is delivered in advance, contrary to be paid after the fulfillment of the task. This practice is meant to transform employees' work attitude from a passive “being told to work” to a more proactive “I want to work” mentality. When such an incentive system is practiced with customers and external distributors, it sends a message that the company is “treating customers as company employees”, which means that they are trusted as if they were part of the company itself. Wu Zishen also introduced a coherent series of leadership practices that generate a truly proactive culture in the organization.

From this case, students will learn how to create a proactive culture in business organizations and the effect of pay-before-performance on employees' work motivation.

Teaching notes and an exercise for class-based discussion are available.