Land-use suitability analyses are of considerable use in the planning of mega-cities. An Urban Development Land-use Suitability Mapping (UDLSM) approach has been constructed, based on opportunity and constraint criteria. Two Multi-criteria Evaluation (MCE) methods, the Ideal Point Method (IPM) and Ordered Weighted Averaging (OWA), were used to generate the opportunity map. The protection map was obtained by means of constraint criteria, utilizing the Boolean union operator. A suitability map was then generated by overlaying the opportunity and protection maps. By applying the UDLSM approach to Beijing, its urban development land-use suitability was mapped, and a sensitivity analysis undertaken to examine the robustness of the proposed approach. Indirect validation was achieved by mutual comparisons of suitability maps resulting from the two MCE methods, where the overall agreement of 91% and kappa coefficient of 0.78 indicated that both methods provide very similar spatial land-use suitability distributions. The suitability level decreases from central Beijing to its periphery, and the area classed as suitable amounts to 28% of the total area. Leading attributes of each opportunity factor for suitability were revealed, with 2256 km(2), i.e. 70%, of existing development land being overlaid by suitable areas in Beijing. Conflicting parcels of land were identified by overlaying the resultant map with two previous development blueprints for Beijing. The paper includes several recommendations aimed at improving the long-term urban development plans for Beijing.

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Rechargeable aqueous zinc‐ion batteries (ZIBs) have aroused tremendous attention in energy storage system due to their high safety, eco‐friendliness, low cost, and for their good compatibility. Transition metal sulfides and selenides are considered to be promising cathodes for aqueous ZIBs owing to their unique layered structure and tunable interlayer spacing for the accelerating diffusion and reversible intercalation of hydrated Zn2+. However, their practical applications are severely impeded by some defects, such as the inferior electronic conductivity, large ion diffusion energy barrier, and bad cyclic stability. In this review, the various modification strategies including phase engineering, defect engineering, interlayer intercalation, in situ electrochemical oxidation, hybridization, doping effects, and surface modification are categorized and highlighted to improve the electrochemical properties of transition metal sulfides and selenides cathode materials, which are discussed and summarized corresponding to particular modification strategies. Finally, several key breakthrough directions such as mechanism exploration technology, electrolyte strategies, synergistic engineering, high‐capacity conversion‐type, high‐voltage cathode materials, and rocking‐chair type batteries are proposed to further push forward the development of aqueous ZIBs, to guide the design of advanced‐properties cathode materials for aqueous ZIBs.

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Over the past half century, a surprising number of major pollution incidents occurred due to tailings dam failures. Most previous studies of such incidents comprised forensic analyses of environmental impacts after a tailings dam failure, with few considering the combined pollution risk before incidents occur at a watershed-scale. We therefore propose Watershed-scale Tailings-pond Pollution Risk Analysis (WTPRA), designed for multiple mine tailings ponds, stemming from previous watershed-scale accidental pollution risk assessments. Transferred and combined risk is embedded using risk rankings of multiple routes of the “source-pathway-target” in the WTPRA. The previous approach is modified using multi-criteria analysis, dam failure models, and instantaneous water quality models, which are modified for application to multiple tailings ponds. The study area covers the basin of Gutanting Reservoir (the largest backup drinking water source for Beijing) in Zhangjiakou City, where many mine tailings ponds are located. The resultant map shows that risk is higher downstream of Gutanting Reservoir and in its two tributary basins (i.e., Qingshui River and Longyang River). Conversely, risk is lower in the midstream and upstream reaches. The analysis also indicates that the most hazardous mine tailings ponds are located in Chongli and Xuanhua, and that Guanting Reservoir is the most vulnerable receptor. Sensitivity and uncertainty analyses are performed to validate the robustness of the WTPRA method.

In this work, switchable synthesis of isoquinolin-1-one and 3-hydroxylisoquinolin-1,4-dione from 2-alkynylbenzamide is reported. The transformation works well with good yields and a broad reaction scope. The synthetic switch for providing isoquinolin-1-one and 3-hydroxylisoquinolin-1,4-dione is enabled by the use of a N2 or O2 atmosphere. Mechanism studies show that the reaction proceeds in a regioselective manner via a N-center radical 6-endo-dig aza-cyclization pathway.