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The assessment of eco-environmental carrying capacity is the focus of planning environmental impact assessment and an important basis for determining whether the planning can be implemented. Based on the theory and method of ECO-environmental impact assessment, this paper applies the analytic hierarchy process (AHP) to analyze the ecological resilience, resource-environment carrying capacity and mining pressure of mineral resources. A comprehensive evaluation model of environmental impact of mineral resources exploitation is established. Taking Shenzhen City, Guangdong Province as an example, the difference of eco-environmental carrying capacity of the main planned mining areas is evaluated. The results show that the pressure bearing degree of most of the assessed blocks is less than 1, indicating that the pressure on the ecosystem is less than the carrying capacity. The ecosystem is not easy to change and can be restored to the original state in a short time after change, and the ecosystem can maintain normal development. This is of great guiding significance to the scientific formulation of mineral resources exploitation strategy.

In this paper, a notch filter (NF) based on silicon photonic crystals (PCs) was proposed and the performance was numerically demonstrated. The structure of NF consists of a beam splitter and two mirrors. Light propagates in NF based on self-collimation (SC) effect. The theoretical transmission spectrum at the output port is simulated using the finite-difference time-domain method (FDTD). The simulation results indicate that changing the radius of the beam splitter or the distance between the mirrors affects the beam transmission effect. This NF is simple in structure, small in size, and based on silicon material, has potential application value in photonic integrated circuits.

In this work, magnetic nanoparticles (MNPs) Fe3O4/CeO2 were firstly synthesized using three different preparation methods, including coprecipitation, impregnation oxidation-precipitation and impregnation reduction-precipitation, respectively. The catalytic activities of Fe3O4/CeO2 MNPs, prepared by above three methods, were compared systematically in terms of the degradation of orange G (OG). The impregnation oxidation-precipitation process was economical and maneuverable due to the usage of air, no need of nitrogen protection and higher utilization efficiency of iron. Response surface methodology based on central composite design were used to investigate the individual and interactive effects of three process parameters on the OG degradation, i.e. the initial pH of the solution, the dosage of H2O2 and the initial concentration of OG. Under the optimal conditions of pH 2.5, H2O2 30 mM, OG 50 mg L−1, catalyst 2.0 g L−1 and 35 °C, the degradation percentage of OG was 98.2% within 120 min, which agreed well with the modeling prediction (R2 = 0.9984, and Adj-R2 = 0.9969). And the degradation reaction well followed the first-order kinetic with R2 = 0.9969. The Fe3O4/CeO2-OX MNPs showed high catalytic activity, stability and reusability in the degradation of OG.

In this work, magnetic nanoparticles (MNPs) Fe

Strategic environmental assessment (SEA) inherently needs to address greater levels of uncertainty in the formulation and implementation processes of strategic decisions, compared with project environmental impact assessment. The range of uncertainties includes internal and external factors of the complex system that is concerned in the strategy. Scenario analysis is increasingly being used to cope with uncertainty in SEA. Following a brief introduction of scenarios and scenario analysis, this paper examines the rationale for scenario analysis in SEA in the context of China. The state of the art associated with scenario analysis applied to SEA in China was reviewed through four SEA case analyses. Lessons learned from these cases indicated the word “scenario” appears to be abused and the scenario-based methods appear to be misused due to the lack of understanding of an uncertain future and scenario analysis. However, good experiences were also drawn on, regarding how to integrate scenario analysis into the SEA process in China, how to cope with driving forces including uncertainties, how to combine qualitative scenario storylines with quantitative impact predictions, and how to conduct assessments and propose recommendations based on scenarios. Additionally, the ways to improve the application of this tool in SEA were suggested. We concluded by calling for further methodological research on this issue and more practices.

This paper advocates a modification of the impact-based approach to strategic environmental assessment (SEA) which seems unable to address institutional weaknesses in most conventional SEA cases in China. It identifies a possible alternative approach, i.e. an impact-centred SEA with institutional components, and presents an analytical framework for institutional analysis, including a four-phase methodology to address and improve institutional weaknesses. Subsequently, the analytical framework is applied to an SEA pilot for a provincial transport plan in China. The case study demonstrates (1) that the proposed approach is adequate even in relatively fixed SEA processes; and (2) that the components and the logical relationships among factors elaborated on in the analytical framework are reasonable. In addition, the components of the framework that need to be improved and the perspectives for future application are discussed.