Morphological Investigation of Solute Particles Trapped from an Air-Acetylene Flame

Abstract

A uniform-droplet generator has been employed to produce individual desolvated KCl particles in a laminar air-acetylene flame. The resulting particles were collected on various surfaces and at different points in their vaporization history. Morphological studies were then conducted on the trapped particles in order to better characterize the structural changes which occur during desolvation and vaporization. Particles collected early in their vaporization exhibited strong crystalline structure characteristic of KCl, whereas particles gathered later in their volatilization history showed evidence of fusion and, in some cases, the formation of hollow spheres. In addition to the morphological studies, the various collection surfaces and the collection technique itself were assessed. Direct collection on scanning-electron microscopy specimen stubs was judged to be best.

Matrix Effect Studies in the Inductively Coupled Plasma with Monodisperse Droplets. Part I: The Influence of Matrix on the Vertical Analyte Emission Profile

“…The erratic emission peaks for the cesium salts in Figs. 3B and 3C may be indicative of inhomogeneous distribution of the m agnesium in the dried particle, or they could be caused by the type of crust formation and droplet``explosion' ' that has been reported in¯ames 22 and in ICPs. 23 Olesik has also reported similar erratic behavior as a result of misalignment of the droplet stream with the central channel of the ICP.…”

Theoretical examination of solute particle vaporization in analytical atomic spectrometry

“…or loose agglomerates during the desolvation process (1,7,44); under these circumstances the surface area and radius of the particle are not the simple consequence of the mass and density of the particle that is assumed in all of the above discussion. Instead, it is possible that a high-surface-area particle is initially produced which exhibits a high vaporization rate.…”

Atomic Emission Spectroscopy—It Lasts and Lasts and Lasts

“…Unfortunately, these experiments were handicapped because conventional nebulizers employed in flame spectrometry produced a broad range of droplet sizes, making it extremely difficult to follow the events that occur to a single droplet. These complications were avoided when it was shown possible to introduce a single droplet or a stream of droplets of known size along a reproducible trajectory into a chemical flame (10)(11)(12)(13)(14)(15)(16)(17)(18)(19). Because each aerosol droplet follows exactly the same path in the flame as all others, and because of the reproducibility of the original droplet size, the progress of each droplet or of multiple droplets in the stream could be followed simply by examining progressively later times in the flame.…”