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Coal waste that releases highly acidic, sulfate and metals rich drainage is a serious environmental problem which causes the contamination of surface and ground water as well as soils in coal mining areas in China. In order to study the effect of using fly ash for preventing acid-mine drainage and controlling heavy metals contamination from coal waste, two column leaching tests were conducted to determine if a cover of fly ash could be used for the control of acid-mine drainage from coal waste. We investigated the effect of the cover of fly ash on controlling acid, sulfate and heavy metals contamination from coal waste. The results from the experimental data analyses show that the cover of fly ash can effectively immobilize cadmium, copper, iron, lead and zinc in acid-mine drainage from coal waste, increase the pH value from 2.0 to 7.5 and decrease Eh from 249 mV to 148 mV, EC from 5.22 mS/cm to 1.05 mS/cm and SO₄^2- concentrations from 12911.7 mg/L to 881.4 mg/L of acid-mine drainage from coal waste. The immobilization rate of heavy metals reached 99%. The oxidation of sulfide minerals in coal waste was prevented by the cover of fly ash, which favors the generation of alkalinity, the decrease of the population of Thiobacillus ferrooxidans, the heavy metals immobilization by precipitation inside the column, and the halt of the oxidation process of sulfide through iron coating on the surface of sulfide minerals in coal waste. The cover of fly ash can effectively control acid-mine drainage and heavy metals contamination from coal waste in situ treatment systems.

The purpose of this paper is to evaluate the properties of several thiol-acrylate photosensitive systems and compare with corresponding acrylate free-radical systems. The potential stereolithography applications of thiol–ene photosensitive systems are also discussed.

In the both thiol–ene and acrylate free-radical photosensitive systems, various key performances were characterized. The function group conversions were characterized by real-time Fourier transform infrared spectroscopy. The tension strength was determined according to the standard ASTM D638-2003, the flexible strength was determined according to ASTM D790-07 and the hardness was measured according to ASTM D2240-05. The volume shrinkage was measured by dilatometer method. The glass transition temperature was analyzed by differential scanning calorimeter.

As adding mercapto propionates into acrylate system, the inhibition of polymerization by oxygen was controlled and the flexible performance was improved. In addition, the photosensitive resin showed better tension strength, higher elongation at break and lower volume shrinkage. Among the four mercapto propionates, rigid TEMPIC showed most obvious affect, followed hexa-functional DPMP, tetra-functional PETMP and tri-functional TMMP.

Although the thiol–ene photosensitive resin has unmatched advantages in performance, there are no reports on the thiol–ene photosensitive resin in the stereolithography application. In this study, thiol–ene photopolymerization material was first tentatively implemented in stereolithography area. Several critical performance parameters were compared between thiol–ene and acrylate free-radical photosensitive systems.

This study aims to explore the repost features of microblogs acting to promote the information diffusion of government-generated content on social media.

This study proposes a topic−sentiment analysis using a mixed social media analytics framework to analyse the microblogs collected from the Sina Weibo accounts of 30 Chinese provincial police departments. On the basis of this analysis, this study presents the distribution of reposted microblogs and reveals the reposting characteristics of police-generated microblogs (PGMs).

The experimental results indicate that children’s safety and crime-related PGMs with a positive sentiment can achieve a high level of online information diffusion.

This study is novel, as it reveals the reposting features of PGMs from both a topic and sentiment perspectives, and provides new findings that can inspire users’ reposting behaviour.

The effect of SBF artificial body fluid on microstructure and morphology characteristics of AZ91D alloy was investigated using OM, SEM and XRD. The effect of corrosion on mechanical properties also was researched.

The results show that the corrosion weight loss rate initially increased, then clearly decreased, and finally remained steady. Pits began to appear when the sample was placed in a corrosive environment for five days and pitting gradually increased with longer exposure time.

The pits, which made the grain boundaries indistinct, first appeared near the grain boundary area and then gradually increased in area.

The main mode of corrosion is pitting and the primary corrosion product, MgOH2, could be observed after five days of corrosion.

It is an established document at the global level that more environmental pollution is associated with more growth of the output for some economies, and on the other hand, more pollution is associated with low growth of output in some other economies. Having the scenario of massive climate change, the global policymakers have been experimenting with drastic reductions in the use of energy and fossil fuels within the target year on 2030 for some countries and 2050 for other countries. The negative impacts of the environmental pollution and the pollution abating targets influence the decision-making processes of the households and business houses around the world. There is thus a potential nexus between the emissions of different greenhouse gases (GHGs) and consumers' and business sentiments in taking optimum decisions. Under this background, this chapter aims to investigate whether GHG emissions and consumers' and business sentiments have any association and interplays for the period 1998–2019 using appropriate econometric exercises. The correlation shows positive results with consumers' sentiments in some developing countries but negative results with business sentiments in some developed countries. Further, there are long-run relationships of GHG with consumers' sentiments and business sentiments in some countries with the mixed results of causal interplays.

The purpose of this paper is to establish the grey relational estimating model of soil pH value based on hyper-spectral data.

As to the uncertainty of the factors affecting the soil pH value estimation based on hyper-spectral, the grey weighted relation estimation model was set up according to the grey system theory. Then the linear regression correction model is established according to the difference and grey relation degree information between the estimated samples and their corresponding pattern. At the same time, the model was applied to Hengshan county of Shanxi province.

The results are convincing: not only that the linear regression correction model of grey relation estimating pattern of soil pH value based on hyper-spectral data is valid, but also the model’s estimating accuracy is higher, which the corrected average relative error is 0.2578 per cent, and the decision coefficient R²=0.9876.

The method proposed in the paper can be used at soil pH value hyper-spectral inversion and even for other similar forecast problem.

The paper succeeds in realising both the soil pH value hyper-spectral grey relation estimating pattern based on the grey relational theory and the correction model of the estimating pattern by using the linear regression.

The aim of this study is to investigate the employee perceptions of organizational support for environmental behaviours and its impact on innovative environmental behaviours and frequency of involvement in upstream oil and gas supply chain management. The study also examines a new area where environmental work culture has been introduced as a facilitator on the relationship between employees’ perceptions and engagement in supply chain management.

Self-administered questionnaires were used for collecting data from supply chain managers in production arrangement contractor and service provider company in Kuala Lumpur. Partial least squares was used for data analysis.

The findings reveal that supervisory support for environmental initiatives and environmental training is positively related to employees’ perception of organizational support for environmental behaviours, while rewards provided by the organization for environmental behaviours are not associated with it. The employees’ perceptions of organizational support for environmental behaviours have a significant impact on employees’ engagement in environmental behaviours in both forms of employees’ frequency of involvement and employees’ innovative environmental behaviours. The findings also show that environmental work culture moderates positively the impacts of organization’s support practices (supervisory support for environmental initiatives and rewards provided by the organization for environmental) on employees’ perception of organizational support for environmental behaviours.

The study critically examines the possible impact of enablers of engagement in environmental behaviours and how employees’ perceptions of organizational support reflect their engagement towards environmental behaviours of the organizational practices. The findings are useful for supply chain management practitioners in terms of exerting environmental behaviours and facilitating employees’ environmental behaviours in the upstream oil and gas supply chain management sector.

The estimation of the effects of treatments – endogenous variables representing everything from child participation in a pre-kindergarten program to adult participation in a job-training program to national participation in a free trade agreement – has occupied much of the theoretical and applied econometric research literatures in recent years. This volume brings together a diverse collection of papers on this important topic by leaders in the field from around the world. This collection draws attention to several key facets of the recent evolution in this literature.