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Inhomogeneous lithium‐ion (Li+) deposition is one of the most crucial problems, which severely deteriorates the performance of solid‐state lithium metal batteries (LMBs). Herein, we discovered that covalent organic framework (COF‐1) with periodically arranged boron‐oxygen dipole lithiophilic sites could directionally guide Li+ even deposition in asymmetric solid polymer electrolytes. This in situ prepared 3D cross‐linked network Poly(ACMO‐MBA) hybrid electrolyte simultaneously delivers outstanding ionic conductivity (1.02 × 10−3 S cm−1 at 30 °C) and excellent mechanical property (3.5 MPa). The defined nanosized channel in COF‐1 selectively conducts Li+ increasing Li+ transference number to 0.67. Besides, The COF‐1 layer and Poly(ACMO‐MBA) also participate in forming a boron‐rich and nitrogen‐rich solid electrolyte interface to further improve the interfacial stability. The Li‖Li symmetric cell exhibits remarkable cyclic stability over 1000 h. The Li‖NCM523 full cell also delivers an outstanding lifespan over 400 cycles. Moreover, the Li‖LiFePO4 full cell stably cycles with a capacity retention of 85% after 500 cycles. the Li‖LiFePO4 pouch full exhibits excellent safety performance under pierced and cut conditions. This work thereby further broadens and complements the application of COF materials in polymer electrolyte for dendrite‐free and high‐energy‐density solid‐state LMBs. [ABSTRACT FROM AUTHOR]

The North China plain (NCP) is an important production base for winter wheat and summer maize in China. Severe droughts seriously restrict agricultural production in this region, threatening food security. Based on the standardized precipitation evapotranspiration index (SPEI), this study explored the spatial and temporal drought characteristics during the winter wheat and summer maize growing seasons in the region. The study found that: 1) From 1980 to 2013, the drought trend of the winter wheat growing season in the NCP has intensified, with Huang-Huai Plain agricultural area (HH_P) showing the most significant drought trend. However, the summer maize growing season has become wetter, with the Shandong hilly agricultural and forestry area (SD_Q) showing the most significant wetting trend. 2) After the year 2003, the results from Mann-Kendall trend analysis revealed that the drought trend of HH_P during the winter wheat growing season became particularly pronounced, but the wetting trend of SD_Q and HH_P during the summer maize growing season became more evident. 3) The dominant spatial patterns observed in the NCP during the growing seasons of winter wheat and summer maize were marked by a consistent distribution of drought and wetness conditions. For winter wheat, the southern regions of the foothill plain area of Yanshan and Taihang Mountains (YT_ P) and the low-lying plain area of Hebei, Shandong, and Henan (JLY_P) were more sensitive to the changes of drought and wet conditions. For summer maize, SD_Q was more sensitive to the changes of the drought and wet conditions. The results of this study could provide references for the formulation of drought relief strategies of winter wheat and summer maize in the NCP. [ABSTRACT FROM AUTHOR]

Droughts frequently occur in Yunnan province, the southwest of China, which leads to crop loss, ecosystem degradation, and difficulties in drinking water for people. In order to assess and compare the extremeness for different drought events, this study quantified it by utilizing the joint return period of drought multi-characteristics. Three characteristics at the regional scale: drought duration, severity, and affected areas were obtained by a simple regional drought process methodology, and their relationship was considered based on three types of Archimedean Copulas. Standard Precipitation Evapotranspiration Index at a six-month time scale was selected as the optimal drought index based on actual drought impact data. Results showed that drought events in Yunnan province were mostly short drought duration, low severity, and high drought-affected areas. By comparing the historical reported droughts' loss, the return periods of drought events calculated by the combination of duration and severity and drought-affected area are much more suitable to reflect the real drought situations than those calculated by one- or two-dimensional drought characteristics, especially for extreme drought events. On average, the drought in Yunnan province was almost shown a return period of ~10 yr. The frequency of droughts in Yunnan province has gradually increased due to climate change, and droughts with ~100 yr or even larger return periods occurred in 2009–2010 and 2011–2013. [ABSTRACT FROM AUTHOR]

Summary: In this article, a new quantum social spider optimization (QSSO) algorithm is proposed. In the QSSO algorithm, we introduce an encoding approach based on bits described on social spider optimization (SSO) and serves as the evolution method of the population space. For the encoding of individuals, the probability amplitude expression of quantum bit is applied to describe the position of individuals, by which one individual's position can be expressed as the superposition of multistates. In such a way, the population diversity and the global searching capability of the SSO algorithm are enhanced. The QSSO algorithm was used to optimize the hydropower station dispatch, and the calculation results show that QSSO algorithm has fast convergence, small number of tuning parameters, high calculation accuracy, stability, simple, and is easy to be implemented with strong global search capability. [ABSTRACT FROM AUTHOR]