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• An integrated heat exposure risk (HER) framework for urban normal heat conditions was refined. • Hourly explicit HER maps at 250 m spatial resolution for various age/gender groups were drawn. • Characterize HER in terms of spatial patterns, temporal dynamics, and population differences. • Novel knowledge for HER configuration by attribute and temporal consistency of risk components. Explicit dynamic and continuous mapping of heat exposure risk (HER) is a vital support for the long-term livability and sustainable management of cities but is rare given the current lack of precisely matching risk-component data. Here, geographic data (rooftops and elevation) and demographic data, particularly the time-matched air temperature data and mobile signaling data both covering 744 periods in one complete month, were used to develop an HER evaluation framework for urban normal heat scenarios and map hour-by-hour outdoor HER with 250 m spatial resolution across Xiamen, China. The results suggested that the mapping analysis was relevant in recognizing the spatial heterogeneity and temporal variability of HER, as well as the population differences in the HER pattern existing under specific spatiotemporal situations for various age (youth/adulthoods/retirement) and gender (male/female) groups. Notably, contributing to better comprehending the HER configuration, high-resolution spatiotemporal mapping was proved to be effective in clearly identifying the detailed time-series evolution of HER by the novel discovery that the definition of 08:00–21:00 as daytime (21:00–08:00 as nighttime) was more consistent with the actual situation of Xiamen than the definition according to sunrise/sunset. These methods and findings provide new knowledge for the zoning prevention and adaptation strategies of HER. [Display omitted] [ABSTRACT FROM AUTHOR]

Abstract The adsorption of 1-alkyl-3-methylimidazolium-type ionic liquids (ITILs) coupled with different counteranions (Tf 2 N−, PF 6 −, BF 4 −, and Cl−) with variational cation alkyl chain lengths (n = 2, 4, 6, and 8) to montmorillonite was investigated to explore the structural effect of ITILs on their adsorption. A series of montmorillonite with different cation exchange capacities (CECs) and possessing a set of homoionic K- and Cs-exchanged interlayer cations were also examined to assess the influence of montmorillonite structure and characteristics. The adsorption of ITILs to Na-saturated montmorillonite (Na-MAz) was counteranion-independent but increased with the increase in the alkyl chain length of the imidazolium cation. X-ray diffraction results indicated that ITIL cations with different alkyl chains lay flat between the montmorillonite interlayers with different contact angles. The uptake of ITILs by Na-MAz increased with the increase in the solution pH and decrease in ionic strength. Na-MAz exhibited greater adsorption than K- and Cs-saturated MAz due to the larger hydrated radii of Na+ than those of K+ and Cs+. The uptake of ITILs to Na-MZj (CEC = 64 mmol/100 g) was almost half compared with that of Na-MAz (CEC = 117 mmol/100 g). Consequently, this work demonstrated that the ITIL adsorption to montmorillonite was dependent on the structures of both adsorbate and adsorbent. Graphical abstract Unlabelled Image Highlights • ITILs adsorption to Na-montmorillonite is counteranion-independent. • ITILs uptake is proportional to the C number of alkyl chain of imidazolium cation. • Na-montmorillonite shows higher ITILs adsorption than K- and Cs-montmorillonite. • Na-montmorillonite with higher CEC exhibits greater ITILs adsorption. [ABSTRACT FROM AUTHOR]