Transfer capillaries are the preferred means to transport ions, generated by electrospray ionization, from ambient conditions to vacuum. During the transfer of ions through the narrow, long tubes into vacuum, substantial losses are typical. However, recently it was demonstrated that these losses can be avoided altogether. To understand the experimental observation and provide a general model for the ion transport, here, we investigate the ion transport through capillaries by numerical simulation of interacting ions. The simulation encompasses all relevant factors, such as space charge, diffusion, gas flow, and heating. Special attention is paid to the influence of the gas flow on the transmission and especially the change imposed by heating. The gas flow is modeled by a one-dimensional gas dynamics description. A large number of ions are treated as point particles in this gas flow. This allows to investigate the influence of the capillary heating on the gas flow and by this on the ion transport. The results are compared with experimental findings.

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转移毛细管是将电喷雾电离产生的离子从环境条件转移到真空的优选方法。在离子通过狭窄的长管传输到真空的过程中，通常会发生大量损失。但是，最近证明了可以完全避免这些损失。为了了解实验观察结果并提供离子迁移的一般模型，在这里，我们通过相互作用离子的数值模拟来研究离子在毛细管中的迁移。该模拟包含所有相关因素，例如空间电荷，扩散，气流和加热。要特别注意气流对变速箱的影响，尤其是加热引起的变化。通过一维气体动力学描述对气流进行建模。在此气流中，大量离子被视为点粒子。这允许研究毛细管加热对气流的影响，并由此对离子传输的影响。将结果与实验结果进行比较。

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