Gradient magnetic micro/nanowire arrays have attracted widespread attention due to their interesting properties. However, fabricating such an ordered array of gradient micro/nanowires with controllable diameters and compositions is still a great challenge to most of the current methods. Here, meniscus-confined electrodeposition (MCED) technique is adopted for the rapid prototyping of the shape-gradient magnetic Cu/Co-alloy microwire arrays by adjusting the printing speed continuously, which provides a novel idea for the preparation and performance research of shape-gradient magnetic alloy microwire arrays with well-defined structures. It is found that the key to fabricating controllable gradient alloy micro/nano structures by increasing the printing speed is to continuously stretch the meniscus within the stable range of the meniscus. In the range of incremental speed in this study, the shape-gradient magnetic alloy wires with stable and uniform compositions and dense internal structures can be successfully prepared, and the gradient ratio can be adjusted from 0 to about 0.025. Compared with the uniform-diameter array, the shape-gradient magnetic alloy array shows an improvement in remanence and coercive force.
Liu Guoliang,Zhang Chunhui,Liu Mengfei,Guo Ziwei,Wang Xinsheng,Yu Cunming,Cao Moyuan
Fundamental research and practical applications have examined the manipulation of gas bubbles on open surfaces in low-surface-tension, high-pressure, and high-acidity, -alkalinity, or -salinity environments. However, to the best of our knowledge, efficient and general approaches to achieve the smart manipulation of gas bubbles in these harsh environments are limited. Herein, a Fluorinert-infused shape-gradient slippery surface (FSSS) that could effectively regulate the behavior of gas bubbles in harsh environments was successfully fabricated. The unique capability of FSSS was mainly attributed to the properties of Fluorinert, which include chemical inertness and incompressibility. The shape-gradient morphology of FSSS could induce asymmetric driving forces to move gas bubbles directionally on open surfaces. Factors influencing gas bubble transport on FSSS, such as the apex angle of the slippery surface and the surface tension of the aqueous environment, were carefully investigated, and large apex angles were found to result in large initial transport velocities and short transport distances. Lowering the surface tension of the aqueous environment is unfavorable to bubble transport. Nevertheless, FSSS could transport gas bubbles in aqueous environments with surface tensions as low as 28.5 ± 0.1 mN/m, which is lower than that of many organic solvents (e.g., formamide, ethylene glycol, and dimethylformamide). In addition, FSSS could also realize the facile manipulation of gas bubbles in various aqueous environments, e.g., high pressure (~ 6.8 atm), high acidity (1 mol/L H 2 SO 4 ), high alkalinity (1 mol/L NaOH), and high salinity (1 mol/L NaCl). The current findings provide a source of knowledge and inspiration for studies on bubble-related interfacial phenomena and contribute to scientific and technological developments for controllable bubble manipulation in harsh environments.
危险品化学品经营许可证（带存储）