Search

In this study, the causal link amid economic growth, fossil fuel energy consumption, carbon emissions and oil price was empirically tested from 1990 to 2015 by using a panel of 22 African countries. The sample of African countries was divided into two subgroups namely; Oil exporters and Non-oil exporters. Using the PMG panel ARDL and panel econometric methods, heterogeneity and cross-sectional dependence were considered to examine the long and short-term dynamic relationships as well as validity of a proposed model. Findings from the Pesaran-Yamagata homogeneity test, Pesaran CD test, CIPS and CADF panel unit root tests and Westerlund-Edgerton bootstrap panel cointegration indicated, the panel time series data has heterogeneity and cross-sectional dependence, analysed variables are stationary and cointegrated respectively. With respect to the PMG panel ARDL estimation method it was evidenced that there exist, (i) a bilateral causal link flanked by fossil fuel energy consumption and economic growth as well as fossil fuel energy consumption and carbon emissions in long and shot-terms for all panels, (ii) a unilateral causality from carbon emissions to economic growth in long-term and short-term for non-oil exporters nonetheless a bilateral causal relationship only in long-term for oil exporting countries, and (iii) a unilateral cause-and-effect link from oil prices to economic growth, energy consumption (fossil fuel) and carbon emission across all country groups in long and short-terms. Policy recommendations are further discussed. [ABSTRACT FROM AUTHOR]

Heterogeneous Fenton dominated by ·OH is limited in its application, as pre-acidification is required to maximize the generation amount and redox potential of ·OH. It is thus featured to consume resources and generate pollutants. In this study, both CuS/H 2 O 2 and Cu 2 S/H 2 O 2 are found to show better performances under close-to-neutral condition (pH 5.0 to 9.0) than acidic condition (pH 3.0) when degrading a model contaminant, sulfamethazine (SMZ), because ·OH does not play a major role in both systems. The Cu valence-dependent catalytic mechanisms are responsible for the varied kinetics between CuS/H 2 O 2 and Cu 2 S/H 2 O 2. In CuS/H 2 O 2 , Cu(III) and 1O 2 contribute to the SMZ degradation, and their contributions are pH-dependent. In Cu 2 S/H 2 O 2 , Cu(III) is responsible for the degradation regardless of the pH. Both systems with optimal performances under neutral condition are advantageous as pre-acidification can be avoided. In addition, air sparging induces additional 16% SMZ degradation in Cu 2 S/H 2 O 2 under acidic condition, because the sparged O 2 reacts with dissolved Cu(I). The more O 2 reacts with the dissolved Cu(I), the less generated Cu(III) is ineffectively depleted. Air sparging is readily applicable to different operations, thus its combination with Cu 2 S/H 2 O 2 potentially benefits the development of environmentally-friendly treatment process for industrial wastewater. • CuS/H 2 O 2 and Cu 2 S/H 2 O 2 are more effective under neutral than acidic condition. • Cu(III) is critical in Cu 2 S/H 2 O 2 , independent of solution pH. • Cu(III) and 1O 2 are critical in CuS/H 2 O 2 , but pH dependent. • Air sparging is an cleaner alternative to improve the Cu 2 S/H 2 O 2 performance. [ABSTRACT FROM AUTHOR]

Although trade does not only boost the economy but also exacerbates environmental transfers but still the evidence for air pollution's unequal exchange embodied in trade among the Belt and Road Initiative (BRI) countries is rarely discussed in the extant literature. From the perspective of an integrated evaluation framework comprising a multi-regional input-output model, system balance theory, and complex network theory, this research paper uncovers the spatial- and temporal changes of trade-induced air pollution inequality among countries along the BRI route for the time period from 2011 to 2016. The study findings point out that there exists an obvious spatial heterogeneity in the unequal relations among BRI economies. This implies that a large number of country pairs demonstrate weak inequalities, whereas a relatively small number of country pairs represent strong inequalities. In addition, the countries' positions indicate a unique characteristic of "duality and inverse", which is majorly manifested as pure causers represented by Moldova and Belarus, net beneficiaries symbolized by China and Russia, and pure victims exemplified by Bhutan. Meanwhile, nearly half of the dual identities are represented by Singapore. Besides this, the proposal and implementation of the BRI exert a positive influence on both system stability and inequality mitigation by supporting the balance of triangles. Finally, this paper posits that the environmental inequality system of the Belt and Road is not as complex as imagined since the 3-node motif classification is relatively simple. Our findings are helpful for mitigating air pollution inequalities so as to support the sustainable development of green BRI. • Evolution of the environmental inequality in BRI countries is studied. • The initiative exerts a positive influence on stability and inequality mitigation. • Most countries illustrate a feature of "duality and inverse". • Five identified subgraphs indicate that the system is predictable. [ABSTRACT FROM AUTHOR]

Phytoextraction is an effective technique for removing cadmium (Cd) from contaminated farmland, thus achieving real ecological restoration. To clarify the potential of peanut phytoextraction, we designed a pot experiment to assess the Cd accumulation in peanut. In addition, the contribution of rhizosphere microorganisms in Cd accumulation was explored. The results demonstrate that the Cd content in peanut tissue ranked as follows: stem > leaf > root > needle > husk > kernel, with Cd mainly accumulated in the stems (41.92%) and leaves (40.27%). The bioconcentration factor for all cultivars was greater than 1, in agreement with the concept of phytoextraction. Cd extraction from peanut plants grown per season was appreciable, estimated as being from 28.5 g Cd ha−1 to 121.5 g Cd ha−1. Subsequently, based on the Cd accumulation characteristics, cultivars BS1016 and HY20 were identified as the high Cd-accumulating cultivars (HACs), and LH11 and LH14 were identified as the low Cd-accumulating cultivars (LACs), for further study as specific cultivars. For Cd-contaminated soil, high accumulation in HACs was associated with increased Cd bioavailability. The peanut rhizosphere attracted different microorganisms to cope with Cd stress. Compared with LACs, the rhizosphere of HACs tended to be enriched with high Cd-resistant microorganisms, which directly or indirectly participate in Cd activation (for example, Acidimicrobiia class of bacteria, Rhizophlyctis genus of fungi). Correlation analysis confirmed that Rhizophlyctis was a good choice to enhance the potential for Cd phytoextraction using peanut. This study demonstrates the advantages and rhizosphere mechanisms of using peanut for bioremediating Cd-contaminated soil, providing a new approach for remediation and targeted regulation of Cd-contaminated farmland. [Display omitted] • The bioconcentration factor of Cd in all peanut tissues was greater than 1. • Peanut has considerable ability to bioaccumulate Cd in aboveground tissues. • High-cadmium peanut cultivars mobilize Cd mainly through soil acidification. • Cultivars and Cd treatments create specific microbial communities in the peanut rhizosphere. • Rhizophlyctis is the most recommended fungus for improving phytoextraction potential. [ABSTRACT FROM AUTHOR]

The low-carbon transition of the energy system plays a crucial role in achieving carbon neutrality. However, the development of new energy heavily relies on rare earth resources, which in turn entail substantial energy consumption and carbon emissions. This "linkage dilemma" poses constraints on the realization of carbon neutrality objectives. In this study, we employ a combination of sample entropy, cross-sample entropy, and coarse-gained network modeling methods to uncover the internal complexity and mutual synchronization of the fossil energy stock market, new energy stock market, rare earth stock market, and carbon market in China. Our findings reveal several important insights. Firstly, we observe that the co-movements among the three industry stock markets and the carbon market are dynamic and closely tied to the efficiency of each market. Secondly, the co-movement between traditional and new energy stock markets remains high, with the supply chain stock market between energy and rare earth exhibiting a similar trend. This highlights the significant impact of inherent substitution or supply chain relationships on the level of synchronization. Thirdly, the stock market crashes and the COVID-19 pandemic have resulted in heterogeneous effects with notable changes observed in carbon-related market pairs. Notably, although the carbon market exhibits relatively low co-movement with other stock markets, the patterns of co-movement and their evolution are becoming increasingly complex. Lastly, based on our findings, we present conclusions and potential implications for policymakers to address the impact of the crisis on market interconnectivity, as well as guide investors to effectively allocate their investment portfolios. [ABSTRACT FROM AUTHOR]

How to encourage individuals to practice green, low-carbon behaviours as an effective way to achieve energy conservation and emission reduction is a scientific and social problem that urgently requires a solution. Considering that a change in individuals' behaviours can be influenced by herd mentality and their own income, in this study, we propose a game model related to individuals' green behaviours (IGB). We divide the relations between individuals into two categories, namely, strong links and weak links, and set some parameters associated with IGB, such as temptation benefit, stubbornness index, and selection preference. Based on a Monte Carlo simulation method, we analyse the key factors affecting IGB. The results show that individuals' blind acquisition of and belief in external information is not conducive to the diffusion of IGB. In addition, if the income of the individuals who do not adopt green behaviours increases, this can greatly inhibit other individuals from adopting green behaviours. Further comparative analysis of the different structures of the underlying network indicates that higher connectivity heterogeneity in the strong links of a network could promote the diffusion of IGB. Furthermore, when individuals' stubbornness is high, the proportion of individuals who adopt green behaviours could also increase. Finally, we analyse how individuals' connectivity and activity rate affect IGB. The results show that people prefer to adopt green behaviours if they exhibit higher connectivity or a lower activity rate. We analysed the important factors affecting IGB, to provide a corresponding basis for promoting IGB scientifically. Image 1 [ABSTRACT FROM AUTHOR]

Inhalable fine particulate matter (PM), which is rich in Pb and other pollutants from coal-fired power plants, can cause air pollution and severe health problems. To facilitate the development of efficient techniques for controlling fine particulate Pb emissions, in this study, various types of size-resolved fine PM (<10.0 μm) were collected from the outlets of fabric filter units (FFs) at an industrial circulating fluidized bed (CFB) power plant to assess the distribution and partitioning behavior of Pb. The results showed that the mass particle size distribution (PSD) of the collected fine PM followed unimodal distribution, peaking at 5.8–4.7 μm, which might be caused by the fragmentation of limestone additives and new-formed CaSO 4. However, the mass PSD of Pb for size-fractionated PM displayed different distribution pattern. Two peaks were observed in the size ranges of 5.8–4.7 μm and 1.1–0.7 μm. The mechanism of Pb enrichment in the supermicron particles was mainly controlled by the surface adsorption reaction, which could be explained by 1/d p dependence and be improved using excess active CaO produced by the injected limestone. For submicron particles, gas-film transfer or heterogenous condensation (mass transfer) might represent the deposition mechanism. Besides Pb enrichment, it was found that the submicron particles (<0.7 μm) mainly consisted of Si-rich and Si–Al phases. The emission of those fine SiO 2 -bearing particles should be limited as they can be inhaled and can damage the respiratory system. Image 1 • The mass PSD of emitted PM 10 (unimodal pattern) differs its Pb fraction (bimodal pattern). • Pb deposited onto supermicron particles was controlled by surface chemisorption. • Pb deposited onto submicron particles might be controlled by heterogenous condensation. • The injection of limestone facilitated Pb enrichment in PM via forming Ca 2 PbO 4 at 600–800 °C. [ABSTRACT FROM AUTHOR]