We propose a coaxial oblique interface shearing (COIS) process for one-step generation of double emulsions which are synchronously sorted with spatial gradient distributions. As a coaxial needle supplying the inner and outer liquids obliquely vibrates across an air-liquid interface, the pinch-off of the compound liquid neck arises and the resultant double emulsions moves with tunable lateral displacements in the receiving phase. In the COIS process, the morphology and size of the double emulsions are heavily dependent on the vibration frequency and the inner and outer liquid flow rates. The lateral droplet displacements changing with process parameters can be precisely controlled in experiments and predicted theoretically by the Stokes drift model. Furthermore, the feasibility of the COIS process in spatial gradient drug release is verified. The double emulsions sorted along a specific direction are available for spatial gradient release under thermal and chemical environments, respectively. The COIS technique has great potential in fields of sensors, spatial gradient materials, advanced drug delivery and biomedical applications.

中文翻译：

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同轴斜交界面剪切：可调谐生成和分选双重乳剂，用于空间梯度药物释放。

我们提出了一种同轴斜交界面剪切（COIS）工艺，用于一步生成双重乳液，并与空间梯度分布进行同步分选。当供应内部和外部液体的同轴针在气液界面上倾斜振动时，复合液体颈的夹断就会出现，并且最终的双乳状液会在接收阶段以可调的横向位移移动。在COIS工艺中，双乳状液的形态和大小在很大程度上取决于振动频率以及内部和外部液体的流速。随工艺参数变化的横向液滴位移可在实验中精确控制，并通过斯托克斯漂移模型进行理论预测。此外，验证了COIS工艺在空间梯度药物释放中的可行性。沿特定方向分选的双重乳液分别可在热和化学环境下用于空间梯度释放。COIS技术在传感器，空间梯度材料，先进的药物输送和生物医学应用领域具有巨大潜力。