Image-charge detection is emerging as an important tool to analyze heavy and heterogeneous samples because of its unique advantages in measuring highly charged microparticles. Conventional image-charge detection instruments include at least three fundamental components: an ionization source, an aerodynamic particle delivery system, and an image-charge detector. Here I report research efforts that investigated the mechanisms of image-charge detection and proposed some instrumental developments of these components to suit specific research purposes. In Chapter 2, I report an investigation of the electrospray ionization (ESI) mechanism based on an observation that a certain portion of charged particles generated with an ESI source carried charges opposite to the needle which is biased with a high voltage. Both biological and non-biological samples were used to shed a light on the complex process of droplet evolution in ESI. In Chapter 3, I present two novel designs of printed circuit board (PCB) based image-charge detectors. With these detectors, not only the charge and velocity of each microparticle were investigated, but also the two dimensional trajectories, with applications in aerosolized particle beam diagnostics. Chapter 4 shows several designs of the microparticle delivering system aiming to achieve a faster acceleration of sample microparticles. Finally, Chapter 5 presents some thoughts on future directions for these projects.
College and Department
Physical and Mathematical Sciences; Chemistry and Biochemistry
BYU ScholarsArchive Citation
Gao, Jiuzhi, "Instrumentation and Application of Image-Charge Detection of Electrospray-Charged Microparticles and Microdroplets" (2020). Theses and Dissertations. 9312.
electrospray ionization, planetary protection, image-charge detection, trajectory detector, mass spectrometry