On-Line Determination of Single Particle Size and Density inthe 5 - 100 nm Diameter Range

提出了一种在线、半自动、 连续测定个体的大小和密度 粒径范围为5 nm至100 nm的颗粒。 这是 通过双尺寸光谱系统完成。 粒子首先通过其斯托克斯直径来确定大小，然后 由它们的空气动力学直径决定大小。 Stokes直径测量 给出了圆形颗粒的几何直径。 空气动力学尺寸也取决于颗粒密度 Stokes直径。 结果是粒子的分布 密度在每个选定的斯托克斯直径。 Stokes尺寸 是通过电动机动性分离，空气动力学 使用单级高超音速撞击器进行尺寸确定。 由于粒子是单电荷的， 可以使用静电计在线测量俘获In。 的 系统在5至100 nm直径范围内有效。

It is proposed a diagnostic method for the on-line, semi- continuous determination of the size and density of individual particles in the 5 nm to 100 nm size range. This is accomplished through a double size spectrometry system. Particles are first sized by their Stokes diameter, and then sized by their aerodynamic diameter. The Stokes diameter sizing gives the geometric diameter of the particle for round particles. The aerodynamic sizing is dependent on particle density as well as Stokes diameter. The result is a distribution of particle densities at each selected Stokes diameter. The Stokes sizing is done by an electrical mobility separation, the aerodynamic sizing is done using a single-stage hypersonic impactor. Since particles are singly charged, the rate of particle capture in can be measured on-line using an electrometer. The system is effective over the 5 to 100 nm diameter range.