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Poly(vinylidene fluoride) (PVDF)-based composite solid electrolytes (CSEs) are attracting widespread attention due to their superior electrochemical and mechanical properties. However, the PVDF has a strong polar group -CF2-, which easily continuously reacts with lithium metal, resulting in the instability of the solid electrolyte interface (SEI), which intensifies the formation of lithium dendrites. Herein, Tetrafluoro-1,4-benzoquinone (TFBQ) was selected as an additive in trace amounts to the PVDF/Li-based electrolytes. TFBQ uniformly formed lithophilic quinone lithium salt (Li2TFBQ) in the SEI. Li2TFBQ has high lithium-ion affinity and low potential barrier and can be used as the dominant agent to guide uniform lithium deposition. The results showed that PVDF/Li-TFBQ 0.05 with a mass ratio of PVDF to TFBQ of 1:0.05 had the highest ionic conductivity of 2.39 × 10−4 S cm−1, and the electrochemical stability window reached 5.0 V. Moreover, PVDF/Li-TFBQ CSE demonstrated superior lithium dendrite suppression, which was confirmed by long-term lithium stripping/sedimentation tests over 2000 and 650 h at a current of 0.1 and 0.2 mA cm−2, respectively. The assembled solid-state LiNi0.6Co0.2Mn0.2O2||Li cell showed an excellent performance rate and cycle stability at 30 °C. This study greatly promotes the practical research of solid-state electrolytes. [ABSTRACT FROM AUTHOR]

Lead pollution has increasingly become the focus of environmental pollution, which is a great harm to the ecological environment and human health. Strict control of the emission of lead pollutants and accurate monitoring of lead are very important. The lead ion detection technologies are introduced here, including spectrophotometry, electrochemical method, atomic absorption spectrometry, and other detection methods, and the methods' applicability, the advantages, and disadvantages are discussed. The detection limits of voltammetry and atomic absorption spectrometry are as low as 0.1 μg/L, and those of atomic absorption spectrometry are as low as 2 μg/L. The detection limit of photometry is higher (0.01 mg/L), but this method can be achieved in most laboratories. The application of different extraction pretreatment technologies in lead ion detection is introduced. The new technologies develop at home and abroad, such as precious metal nanogold technology, paper microfluidic technology, fluorescence molecular probe technology, spectroscopy, and other emerging technologies in recent years, are reviewed, and the principle and application of various technologies are expounded. [ABSTRACT FROM AUTHOR]

Featured Application: Water is the source of life. It is both food for human beings and necessary for the existence of the whole ecological system. With the development of society, there are more and more water pollutants. Water detection technology needs modernization, intelligence, and speed. The chloride ion, an anion that is widespread in nature, will have harmful effects on industrial and agricultural production and ecology when its levels are too high. How to quickly and timely monitor chloride ions is an important question for industrial production, agricultural production, human activities, and ecological health. The chloride ion (Cl−) is a type of anion which is commonly found in the environment and has important physiological functions and industrial uses. However, a high content of Cl− in water will do harm to the ecological environment, human health and industrial production. It is of great significance to strictly monitor the Cl− content in water. Following the recent development of society and industry, large amounts of domestic sewage and industrial sewage are discharged into the environment, which results in the water becoming seriously polluted by Cl−. The detection of Cl− has gradually become a research focus. This paper introduces the harm of Cl− pollution in the environment and summarizes various Cl− detection methods, including the volumetric method, spectrophotometry method, electrochemical method, ion chromatography, paper-based microfluidic technology, fluorescent molecular probe, and flow injection. The principle and application of each technology are described; their advantages, disadvantages, and applicability are discussed. To goal of this research is to find a more simple, rapid, environmental protection and strong anti-interference detection technology of Cl−. [ABSTRACT FROM AUTHOR]

ZnO quantum dots were synthesized by chemical precipitation, CuFe 2 O 4 nanoparticles were prepared by in situ synthesis of cellulose, and then ZnO/CuFe 2 O 4 (ZCF) composites were fabricated. A photocatalyst (ZCF@MB-MIP) with specific molecule recognition and photocatalytic degradation characteristics was then produced by a surface imprinting method using methylene blue (MB) as the template molecule. The structure of ZCF@MB-MIP was characterized by Fourier transform infrared spectroscopy, transmission electron microscopy and X-ray diffraction. The photocatalytic efficiency of ZCF@MB-MIP and its specific recognition performance in MB degradation was analyzed. The adsorption kinetics of MB by ZCF@MB-MIP conformed to the quasi-secondary adsorption kinetics model. ZCF@MB-MIP displayed effective photocatalytic degradation of MB under natural light. The degradation rate reached 95.8%, which was much higher than those of ZCF, CuFe 2 O 4 nanoparticles, and a non-imprinted reference sample under the same conditions. This work is a useful reference for the construction of photocatalysts that show highly selective recognition of dye molecules. A novel molecularly imprinted catalyst was prepared and its fluorescence characteristics were studied. Image 1 [ABSTRACT FROM AUTHOR]

Simple Summary: Riptortus pedestris (Fabricius) is a serious pest of soybeans. The nymphs and adults of R. pedestris cause feeding injury to soybean pods, resulting in significant field damage losses. In this paper, we tested the damage to soybeans at different growth stages caused by different densities of R. pedestris, through the field cage test. Our results showed that R4 was the most sensitive stage to R. pedestris injury. The damage intensity of the soybeans increased with increased pest density, and soybean nutrition factors changed after suffering R. pedestris injury. These results will be beneficial to future management programs of R. pedestris in soybean fields. The bean bug, Riptortus pedestris, is a major pest of soybeans. In order to assess the critical stages of soybean damage by R. pedestris, we tested the damage to soybeans at different growth stages (R2, R4, and R6) caused by five densities of R. pedestris (1, 2, 3, 4, and 5) through a field cage experiment. The results show that the R4 stage was the most sensitive stage in terms of suffering R. pedestris injury damage, followed by the R6 stage and then the R2 stage. The number of stay green leaves was 7.04 per plant, the abortive pod rate of the soybeans was 56.36%, and the abortive seed rate of the soybeans was 46.69%. The dry weight of the soybeans was 14.20 g at the R4 stage; these values of R4 were significantly higher than at the R2 and R6 stages. However, the dry weight of soybean seed was 4.27 g and the nutrient transfer rate was 27.01% in the R4 stage; these values were significantly lower than in the R2 and R6 stages. The number of stay green leaves, abortive pod rates, and abortive seed rates were all increased significantly with increasing pest density at each stage of soybean growth. However, the nutrient transfer rate was significantly decreased with the increase in the pest density. Soybean nutrition factors changed after they suffered R. pedestris injury; the lipid content of the soybean seed decreased and the lipid content of the soybean plant increased compared to controls, when tested with a density of five R. pedestris in the R4 stage. These results will be beneficial to the future management of R. pedestris in soybean fields. [ABSTRACT FROM AUTHOR]

In present work, ZrO 2 -5 wt% Al 2 O 3 and ZrO 2 -10 wt% Al 2 O 3 nanocomposites are fabricated through spark plasma sintering. Al 2 O 3 –ZrO 2 amorphous powders and polycrystal Al 2 O 3 powders and are doped in the polycrystalline ZrO 2 powders, respectively. When doped with amorphous powders, the sintering of ZrO 2 –Al 2 O 3 nanocomposites is promoted, and ZrO 2 -5 wt% Al 2 O 3 and ZrO 2 -10 wt% Al 2 O 3 nanocomposites with relative densities of 99% are obtained after spark plasma sintering at 1200 °C; however, when sintering of polycrystalline ZrO 2 and polycrystalline Al 2 O 3 powders, the relative densities are merely 93%. The enhanced sinterability is due to the metastability and phase transformation of the amorphous powders, which act as sintering aids. The nanocomposites with near-theoretical density show refined microstructure with homogenous mixture of ZrO 2 and Al 2 O 3 grains, which further leads to excellent mechanical properties. This article provides new ideas for low-temperature sintering of nanocomposites via using doping amorphous powders. • Effect of different dopants, i.e., polycrystal Al 2 O 3 powders and Al 2 O 3 –ZrO 2 amorphous powders on sintering of ZrO 2 –Al 2 O 3 nanoceramics was investigated. • The doping of amorphous powders highly promoted the sintering, due to the phase transition in metastable amorphous powders. • ZrO 2 - 5 wt%Al 2 O 3 and ZrO 2 - 10 wt%Al 2 O 3 nanoceramics were obtained through SPS at 1200 °C, and showed fine microstructures and superior mechanical properties. [ABSTRACT FROM AUTHOR]