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In order to obtain line parameters instantaneously， efficiently and accurately during overhead transmission line patrol， line trajectories are fitted by catenary equation and UAV. This paper， out of the need of measurement， designs a system to quickly calculate the sag distance of conductors of transmission lines， span lengths of poles and towers， and the arc sag distance of cross-span on cross-span lines by using UAV with the catenary equation to fit the power line trajectory. The system innovatively proposes establishing a new spatial coordinate system （conversion from geographic to Web Mercator projection coordinate system） to calculate data in transmission lines. Calculation results show that the system has high accuracy， low operation cost， and high engineering application value.

Electrocatalytic alcohol oxidation (EAO) is an attractive alternative to the sluggish oxygen evolution reaction in electrochemical hydrogen evolution cells. However, the development of high-performance bifunctional electrocatalysts is a major challenge. Herein, we developed a nitrogen-doped bimetallic oxide electrocatalyst (WO-N/NF) by a one-step hydrothermal method for the selective electrooxidation of benzyl alcohol to benzoic acid in alkaline electrolytes. The WO-N/NF electrode features block-shaped particles on a rough, inhomogeneous surface with cracks and lumpy nodules, increasing active sites and enhancing electrolyte diffusion. The electrode demonstrates exceptional activity, stability, and selectivity, achieving efficient benzoic acid production while reducing the electrolysis voltage. A low onset potential of 1.38 V (vs. RHE) is achieved to reach a current density of 100 mA cm−2 in 1.0 M KOH electrolyte with only 0.2 mmol of metal precursors, which is 396 mV lower than that of water oxidation. The analysis reveals a yield, conversion, and selectivity of 98.41%, 99.66%, and 99.74%, respectively, with a Faradaic efficiency of 98.77%. This work provides insight into the rational design of a highly active and selective catalyst for electrocatalytic alcohol oxidation. [ABSTRACT FROM AUTHOR]

Electrochemical oxidation is an energy-efficient and environmentally friendly reaction mode, but it is limited by the difficulty of fabricating electrode systems that can efficiently perform high-yield oxidation reactions at low potentials. Herein, we prepared V–N supported electrocatalysts with nickel foam as the electrode substrate (VO-N/NF nanocomposite) for electrocatalytic benzyl alcohol oxidation by a one-step hydrothermal method. Specifically, the VO-N/NF nanocomposite electrode can reach a current density of 100 mA cm−2 at a low voltage of 1.395 V (vs. RHE) in 1.0 M KOH electrolyte with only 0.2 mmol metal precursor. The synergistic effect of high-valent nickel-based compounds, as well as the exposed active sites resulting from the dissolution of V elements in the process, makes it super-efficient and profitable for electrocatalytic oxidation. The best proof is that the conversion, selectivity, and faradaic efficiency reach 99.7%, 99.5%, and 99.3%, respectively. Meanwhile, the electrode performance remains good after repeated reactions, with the conversion of benzyl alcohol and faradaic efficiency both being above 98.5%. The design of the electrode provides a new idea to broaden the range of organic reactions carried out by electrocatalysis. And it also helps to reduce the high overpotential caused by the original oxygen evolution reaction. [ABSTRACT FROM AUTHOR]

Microneedle arrays show many advantages in drug delivery applications due to their convenience and reduced risk of infection. Compared to other microscale manufacturing methods, 3D printing easily overcomes challenges in the fabrication of microneedles with complex geometric shapes and multifunctional performance. However, due to material characteristics and limitations on printing capability, there are still bottlenecks to overcome for 3D printed microneedles to achieve the mechanical performance needed for various clinical applications. The hierarchical structures in limpet teeth, which are extraordinarily strong, result from aligned fibers of mineralized tissue and protein‐based polymer reinforced frameworks. These structures provide design inspiration for mechanically reinforced biomedical microneedles. Here, a bioinspired microneedle array is fabricated using magnetic field‐assisted 3D printing (MF‐3DP). Micro‐bundles of aligned iron oxide nanoparticles (aIOs) are encapsulated by polymer matrix during the printing process. A bioinspired 3D‐printed painless microneedle array is fabricated, and suitability of this microneedle patch for drug delivery during long‐term wear is demonstrated. The results reported here provide insights into how the geometrical morphology of microneedles can be optimized for the painless drug delivery in clinical trials. [ABSTRACT FROM AUTHOR]