The contributions of the poly(methylbenzene) (polyMB) and alkene cycles to the methanol to propene (MTP) process in H-FAU zeolite have been investigated by a two-layer ONIOM (our own n-layered integrated molecular orbital and molecular mechanics) method, which is important to understand the nature of formation of propene in zeolite with large pore sizes. The calculated results demonstrate that the different pathways in the polyMB cycle occur in the following order of reactivity: methyl-transfer pathway > spiro pathway > direct internal H-shift > paring pathway. The polyMB cycle is more competitive than the alkene cycle for the MTP process in H-FAU, which is different from the previous results on H-ZSM-5. Introduction of Li + and Ag + cations into FAU zeolite does not reduce the free energy barriers of the methylation steps involved in polyMB and alkene cycles, indicating that the experimental efforts to improve propene selectivity probably should focus on the physical effect of Li + and Ag + cations. For the step of formation of propene in both cycles, the difference in charge densities suggests a clear electron transfer between the propene fragment and the aromatic ring or propoxy group. Decomposing ONIOM energy barriers into quantum mechanics and molecular mechanics contributions suggests that the stabilizing effect of the zeolite environment on transition states mainly originates from the van der Waals interactions for the spiro and methyl-transfer pathways in the polyMB cycle, but from the electrostatic interactions for the alkene cycle. Generally speaking, the formation step of propene is entropy-increased. The direct internal H-shift and paring pathways are entropy-decreased. The entropy effect in the alkene cycle is larger than that in the polyMB cycle due to the larger entropic barriers.

Urban pluvial flooding now occurs more frequently than it has in past decades, mainly due to an increasing number of extreme precipitation events occurring in the context of a changing climate. To limit the evolving risks of urban pluvial flooding in a more environmentally friendly manner, the research community has recently paid increasing attention to Nature-Based Solutions (NBS), which are based on new green technologies. To meet the urgent demand for a comprehensive review of the most recent literature, this review conducts a systematic survey of the literature to characterize various NBS adopted in different regions of the world and to elaborate on the benefits and limitations of such NBS. The review highlights the role of NBS in urban flood risk management under ongoing climate change and rapid urbanization. It shows that NBS could effectively mitigate urban flooding caused by high-frequency precipitation events, with additional economic, ecological, and social benefits. However, NBS are less effective at helping cope with pluvial flooding caused by extreme precipitation events over a short period of time, while gray infrastructures also have limitations as a mitigation measure against extreme pluvial flooding. We thus recommend identifying flood risk management strategies by evaluating the performance of alternative combinations of NBS with gray infrastructures in preventing pluvial flooding in the cities. Finally, recent advances made in the applications of NBS are presented with suggestions (e.g., long-term monitoring) to improve urban flood adaptive management. This article is categorized under: Engineering Water > Planning Water Engineering Water > Sustainable Engineering of Water Science of Water > Water Extremes K E Y W O R D S extreme precipitation, nature-based solution, risk management, urban pluvial flood Yijing Huang and Zhan Tian equally contributed to this study.[Correction added on 27 April 2020, after first online publication: the unit of second affiliation has been updated and funding information has been reordered.]

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Chinese Medicinal Yam (CMY) has been prescribed as medicinal food for thousand years in China by Traditional Chinese Medicine (TCM) practitioners. Its medical benefits include nourishing the stomach and spleen to improve digestion, replenishing lung and kidney, etc., according to the TCM literature. As living standard rises and public health awareness improves in recent years, the potential medicinal benefits of CMY have attracted increasing attention in China. It has been found that the observed climate change in last several decades, together with the change in economic structure, has driven significant shift in the pattern of the traditional CMY planting areas. To identify suitable planting area for CMY in the near future is critical for ensuring the quality and Dongli Fan and Honglin Zhong have contributed equally to this work.Environ Geochem Health (2020) 42:987-1000 https://doi.org/10.1007/s10653-019-00437-w( 0123456789().,-volV) (0123456789().,-volV) Hebei, and western Shandong. The climate suitability of these areas will be improved due to global warming in the next 50 years, and therefore, they will continue to be the most suitable CMY planting regions.