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Replacing liquid electrolytes with solid‐state polymer electrolytes (SPEs) can solve the safety hazards of Li metal batteries (LMBs) while increasing their energy density. However, there has been limited success so far in preparing advanced SPEs with controllable molecular structure and chemical composition, posing great obstacles to further promoting its application in LMBs. Recently, ring‐opening polymerization (ROP), including cationic ROP, anionic ROP, and ring‐opening metathesis polymerization, has become a dazzling new star in achieving SPEs due to its mild polymerization conditions and controllable chemical composition (molecular structure, functional group), etc. Besides, there is no small molecule released during the polymerization process, which means reduced interfacial side reaction. Hence, in this review, the merits of ROP in preparing SPEs and its mechanism as well as interfering factors, etc are evaluated from the perspective of synthetic chemistry. Furthermore, the review focuses on outlining the existing cases related to ROP as much as possible and summarize them from different ring structures (from triple ring to multivariate ring) and polymerization methods, hoping to provide a comprehensive understanding and serve as strategic guidance for designing high‐performance SPEs. Challenges and opportunities regarding this burgeoning field are also discussed at the end. [ABSTRACT FROM AUTHOR]

Wetlands have powerful runoff regulation functions, which can effectively store and retain surface runoff. The runoff regulation function of wetlands is affected by wetland areas, which affect the capacity of flood control. To explore the law of the area change of the main wetlands of the Naolihe River Basin (MWNRB), the visual interpretation method was used to extract wetlands. To identify the reasons for area changes in the MWNRB, the maximum likelihood method, minimum distance method, and neural network method were used to classify land use types from remote sensing images; the M-K variation point test and Theil-Sen trend analysis were used to test the variation point and calculate the trend of precipitation and temperature series. To clarify the influence of wetland areas on runoff, the Gini coefficient and SRI of runoff were used to calculate runoff temporal inhomogeneity. The results showed that the area of the MWNRB obviously decreased, with 74.5 × 106 m2/year from 1993 to 2008, and increased slowly from 2008 to 2015, with 27.7 × 106 m2/year. From 1993 to 2008, 50.74% and 38.87% of wetlands were transformed into paddy fields and dry fields, respectively. From 2008 to 2015, 61.69% and 7.76% of wetlands were transformed from paddy fields and dry fields, respectively. The temperature of the MWNRB increased slowly by 0.04 °C/year from 1993 to 2008 and increased obviously by 0.16 °C/year from 2008 to 2015. The precipitation decreased by 5.6–8.1 mm/year and increased by 16.6–41.2 mm/year in 1993–2008 and 2008–2015, respectively. Compared with precipitation and temperature, land use change caused by human activities is the main cause of wetland area change. The area change of the MWNRB has a certain influence on the runoff regulation and storage capacity. The Gini coefficient and SRI index increased from 0.002/year (0.008) to 0.023/year from 1993 to 2008 and decreased from 0.046/year (0.045) to 0.161/year from 2008 to 2015, respectively. [ABSTRACT FROM AUTHOR]

AgIn5S8/ZnS (AIS/ZS) core/shell quantum dots (QDs) have been synthesized using a hot injection method at relatively low temperature without any protection using inert gas. The QDs were characterized with UV visible electronic absorption spectroscopy, PL spectroscopy, Fourier transform infrared (FT-IR) spectroscopy, transmission electron microscopy (TEM), and temperature-dependent time-resolved PL (TRPL). The average size of the QDs was determined to be 1.73 ± 0.29 nm. The QDs exhibit a major excitonic absorption band peaked at 479–573 nm and emission bands peaked from 548 to 666 nm with excitation at 410 nm with the peak position dependent on the synthesis temperature that affects the QD size. Upon the addition of trioctylphosphine (TOP) as a ligand, the PL quantum yield (PLQY) increased to 74.1% compared to 56.7% without TOP. The QDs show high stability after hours of ultraviolet (UV) light exposure or repetitive treatment with a significant amount of polar solvents, which is attributed to surface passivation by the ligands and ZnS shell. The luminescence mechanism of the core/shell AIS/ZS QDs is ascribed to donor–acceptor pair (DAP) recombination. TRPL results suggest that the binding energy of DAP increases and the DAP recombination probability is enhanced after passivation with TOP, leading to the high PLQY. Furthermore, prototype highly pure white light-emitting diodes (LEDs) based on these AIS/ZS QDs have been successfully demonstrated, yielding ideal 1931 CIE coordinates of (0.327, 0.335). [ABSTRACT FROM AUTHOR]

Noise‐like pulses (NLPs) are becoming increasingly attractive for a variety of applications such as supercontinuum generation, materials processing, and low‐coherence spectral interferometry. Related research in the near‐infrared region is extensive, yet few studies have been reported in the mid‐infrared (MIR) region. Herein, a systematic investigation of MIR NLPs is made for the first time. An approach is presented by exploiting a polarization‐maintaining fluoride fiber in the mode‐locked oscillator to cause a polarization‐dependent delay between the orthogonal‐polarized components of intracavity circulating pulses, thus generating a series of ultrashort pulses which will eventually form a stable wave packet, namely, NLP. Numerical simulations based on the extended coupled nonlinear Schrödinger equations predict the generation of NLPs, and reveal key aspects of the pulse evolution. Experiments yield linearly polarized NLPs at 2.8 μm with a maximum average power of 498 mW and a spike width of 4.3 ps, corresponding to a pulse energy of 12 nJ. The experimental results are in good agreement with the simulation results. This work constitutes a major step toward the development of MIR ultrafast fiber lasers with NLPs output. [ABSTRACT FROM AUTHOR]

As more and more power users are increasingly demanding the quality of electricity, the losses caused by voltage sags are becoming more and more serious. Therefore, it is very important to analyze the cause of the voltage sag to prevent the voltage sag in time. This paper proposes a new algorithm that combines Apriori correlation analysis algorithm and cluster analysis algorithm to analyze the causes of voltage sags. Because some typical climatic conditions also have an important influence on the cause of voltage dips, The data is initially processed using climate factors as clustering indicators, and then the correlation analysis between typical electrical characteristics and voltage sags is performed, and strong association rules are finally obtained. According to the calculation and analysis of examples, some factors with high correlation with the causes of voltage sag are found, which will provide theoretical support for the prevention of voltage sag and provide ideas for further research on the causes of voltage sag.

Lithium metal batteries hold promise for energy storage applications but suffer from uncontrolled lithium dendrites. In this study, a new composite membrane based on modified natural polymer and ZIF‐67 is designed and prepared by the in situ composite method for the first time. Among them, a modified natural polymer composed of lithium alginate (LA) and polyacrylamide (PAM) can be obtained by electrospinning. Importantly, the polar functional groups of natural polymers can interact by hydrogen bonding and MOFs can construct lithium‐ion transport channels. Consequently, compared with LA‐PAM electrolyte without MOF, the electrochemical stability window of ZIF‐67‐LA‐PAM electrolyte becomes wider from 4.5 to 5.2 V, and the lithium‐ion transference number (tLi+) enhances from 0.326 to 0.627 at 30°C. It is worth noting that the symmetric cells with ZIF‐67‐LA‐PAM have superior stable cycling performance at 40 and 100 mA cm−2, and a high rate at 10C and 20C for LFP cells. Besides, the cell with NCM811 high‐voltage cathode can run stably for 400 cycles with an initial discharge capacity of 136.1 mAh g−1 at 0.5C. This work provides an effective method for designing and preparing MOF‐natural polymer composite electrolytes and exhibits an excellent application prospect in high‐energy‐density lithium metal batteries. [ABSTRACT FROM AUTHOR]