Abstract The application of standard online instrumentation, such as scanning mobility particle sizer (SMPS), centrifugal particle mass analyzer or aerosol particle mass analyzer (CPMA/APM), and electrical low-pressure impactor (ELPI+) to low-pressure processes is only possible with extensive modification of the devices and extensive calibrations. A low-pressure ejector is a suitable device to transfer aerosol nanoparticles from low-pressure regions to atmospheric pressure and allows the direct use of standard online instrumentation. In this work, a commercial low-pressure ejector is investigated in the pressure range from 20–180 mbar with fully-sintered and size-selected nanoparticles (15–80 nm) in order to extend the application range of online instruments to low-pressure processes and open up a new variety of analysis methods. Results are compared to our previous work which was limited to pressures above 120 mbar. A change in particle size during the measurements for fully-sintered silver particles was not observed. A particle dilution factor between 60–6500 was found. High particle losses in the ejector for large particle sizes are compensated by a lower gas dilution factor.

中文翻译：

---

基于喷射器的纳米颗粒采样压力低至 20 毫巴

摘要 扫描迁移率粒度仪 (SMPS)、离心式颗粒质量分析仪或气溶胶颗粒质量分析仪 (CPMA/APM) 和电动低压冲击仪 (ELPI+) 等标准在线仪器仅可应用于低压过程。对设备进行大量修改并进行大量校准。低压喷射器是将气溶胶纳米粒子从低压区域转移到大气压的合适设备，并允许直接使用标准在线仪器。在这项工作中，研究了一种商业低压喷射器，压力范围为 20-180 mbar，具有完全烧结和尺寸选择的纳米颗粒（15-80 nm），以将在线仪器的应用范围扩展到低压过程并开辟了多种新的分析方法。结果与我们之前的工作进行了比较，该工作仅限于 120 毫巴以上的压力。在完全烧结的银颗粒的测量过程中没有观察到颗粒尺寸的变化。发现粒子稀释系数在 60-6500 之间。对于大颗粒尺寸，喷射器中的高颗粒损失通过较低的气体稀释系数得到补偿。