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Binary transition metal sulfides have garnered widespread concentration result from their superior electrical conductivity and outstanding capacitance. However, their poor cycling stability hinders their applications in energy storage devices. The objective of this study is to devise and prepare graphene and NiCo2S4 composite (NiCo2S4@graphene) using a simple one-step hydrothermal modality. Graphene is used as a conductive substrate, and NiCo2S4 nanoparticles are formed in situ and homogeneously anchored on graphene nanosheets through C-S-C covalent bonds. For example, the NiCo2S4@graphene composite has a high specific capacitance of 918.0 C g−1 at a current density of 1 A g−1 and enhanced cycling stability (90.1% after 6000 cycles). In addition, the asymmetric supercapacitor was fabricated with NiCo2S4@graphene as the positive electrode and graphene (GR) as the negative electrode, and the device provided a maximum energy density of 49.8 Wh kg−1 at a power density of 845.3 Wh kg−1. Besides, the capacitance retention rate was as high as 92.0% after 1000 cycles. The superior electrochemical properties of the NiCo2S4@graphene material verified its huge potential for realistic applications. [ABSTRACT FROM AUTHOR]

Simple Summary: Corn ear pests, such as cotton bollworm and corn borer larvae, can infest corn ears within hours to a day, posing a significant challenge for their control. This study aimed to determine the ideal timing for pesticide application, select effective and safe pesticides, and optimize application methods. Over several years, we monitored adult sweet corn ear pests in Beijing, investigating their relationship with corn phenology and local climate to identify the best time for effective pesticide application. Through field experiments evaluating 13 different pesticides, we identified cost-effective and safe options. Ultimately, we discovered that in mid-June, approximately five days after corn silking in sweet corn fields, moth populations got the greatest growth rate. During this crucial period, applying Indoxacarb + Chlorfenapyr, Virtako + mineral oil, or the biopesticide Beauveria bassiana + oil on corn silks and ear surfaces maximized their effectiveness. Our research significantly improves corn ear pest control. Helicoverpa armigera (Hübner) and Ostrinia furnacalis (Guenée) are the most devastating insect pests at the ear stage of maize, causing significant losses to the sweet corn industry. Pesticide control primarily relies on spraying during the flowering stage, but the effectiveness is inconsistent since larvae are beneath husks within hours to a day, making pesticide treatments simpler to avoid. Insufficient understanding of pest activity patterns impedes precise and efficient pesticide control. H. armigera and O. furnacalis in corn fields were monitored in the last few years in Beijing China, and we observed a higher occurrence of both moths during the R1 stage of sweet corn. Moth captures reached the maximum during this stage, with 555–765 moths per hectare corn field daily. The control efficiency of nine synthetic insecticides and five biopesticides was assessed in the field during this period. Virtako, with mineral oil as the adjuvant, appeared to be the most effective synthetic insecticide, with the efficiencies reaching 88% and 87% on sweet and waxy corn, respectively. Pesticide residue data indicated that the corn is safe after 17 days of its use. The most effective bioinsecticide was Beauveria bassiana combined with mineral oil, with 88% and 80% control efficiency in sweet and waxy corn, respectively. These results suggested that spraying effective insecticides 5 days after corn silking could effectively control corn ear pests H. armigera and O. furnacalis. Our findings provide valuable insights for the development of ear pest management strategies in sweet corn. [ABSTRACT FROM AUTHOR]

Recently, fluorescent covalent staining methods have been developed for visualization of anatomical structures in cells and tissues. Coupled with expansion microscopy, these stains revealed various ultrastructural details. However, the covalently stainable chemical groups have been limited to amines, carbohydrates, and thiols. Here, we developed procedures for covalently labeling tissues for carboxylate and phosphate groups, utilizing carbodiimide crosslinker chemistry. In porcine kidney tissues, the carboxylate and phosphate stain provides 1.8–4.8‐fold higher signal intensity than those from the three existing stains. In cancer cells, such stain allows 2–8‐fold more accurate identification of nucleoli than the amine stain. In expansion microscopy samples, such stain reveals a variety of sub‐cellular structures in tissues when combined with the amine stain. Such stain also allows imaging of lipid‐based structures in cultured cells. With these advantages, this new covalent staining method further expands the toolset for fluorescent visualization of histology. [ABSTRACT FROM AUTHOR]

Molybdenum dioxide (MoO2) demonstrates a big potential toward lithium‐ion storage due to its high theoretical capacity. The sluggish reaction kinetics and large volume change during cycling process, however, unavoidably lead to inferior electrochemical performance, thus failing to satisfy the requirements of practical applications. Herein, we developed a molybdenum‐based oxyacid salt confined pyrolysis strategy to achieve a novel hierarchical porous MoO2@Mo2N@C composite. A two‐step successive annealing process was proposed to obtain a hybrid phase of MoO2 and Mo2N, which was used to further improve the electrochemical performance of MoO2‐based anode. We demonstrate that the well‐dispersed MoO2 nanoparticles can ensure ample active sites exposure to the electrolyte, while conductive Mo2N quantum dots afford pseudo‐capacitive response, which conduces to the migration of ions and electrons. Additionally, the interior voids could provide buffer spaces to surmount the effect of volume change, thereby avoiding the fracture of MoO2 nanoparticles. Benefiting from the aforesaid synergies, the as‐obtained MoO2@Mo2N@C electrode demonstrates a striking initial discharge capacity (1760.0 mAh g−1 at 0.1 A g−1) and decent long‐term cycling stability (652.5 mAh g−1 at 1.0 A g−1). This work provides a new way for the construction of advanced anode materials for lithium‐ion batteries. [ABSTRACT FROM AUTHOR]

At present, the selective hydrogenation of α, β-unsaturated aldehydes remains a challenge due to competition between unsaturated functional groups (C=C and C=O). In this study, N-doped carbon deposited on silica-supported nickel Mott–Schottky type catalysts (Ni/SiO2@NxC) was prepared for the selective hydrogenation of cinnamaldehyde (CAL) by using the respective hydrothermal method and high-temperature carbonization method. The prepared optimal Ni/SiO2@N7C catalyst achieved 98.9% conversion and 83.1% selectivity for 3-phenylpropionaldehyde (HCAL) in the selective hydrogenation reaction of CAL. By constructing the Mott–Schottky effect, the electron transfer from metallic Ni to N-doped carbon at their contact interface was promoted, and the electron transfer was demonstrated by XPS and UPS. Experimental results indicated that by modulating the electron density of metallic Ni, the catalytic hydrogenation of C=C bonds was preferentially performed to obtain higher HCAL selectivity. Meanwhile, this work also provides an effective way to design electronically adjustable type catalysts for more selective hydrogenation reactions. [ABSTRACT FROM AUTHOR]

We propose and demonstrate the effectual generation and control of nonparaxial self-accelerating beams by using UV-resin pendant droplets. We show that the geometrical shape of the hanging droplets formed as a result of the interplay between surface tension and gravity offers a natural curvature enabling the generation of nonparaxial self-accelerating beams. By simply adjusting the tilt angle of the surface where the droplets reside, a passing light beam is set to propagate along different curved trajectories, bending into large angles with non-diffracting features superior to a conventional Airy beam. Such self-accelerating beams are directly traced experimentally through the scattered light in yeast-cell suspensions, along with extensive ray tracing and numerical simulations. Furthermore, by modifying the shape of uncured pendant resin droplets in real time, we showcase the dynamical trajectory control of the self-accelerating beams. Our scheme and experimental method may be adopted for the droplet-based shaping of other waves such as microfluidic jets and surface acoustic waves. [ABSTRACT FROM AUTHOR]