Platform-to-platform sample transfer, distribution, dilution, and dosing via electrothermal vaporization and electrostatic deposition

An electrothermal vaporization unit with axially focusing convection upstream and influence of modifiers. Part I: Experimental

“…Various constructions of electrothermal vaporization (ETV) cells have been used as sample introduction tools for inductively coupled plasma optical emission and mass spectrometry (ICP-OES/MS) [1][2][3][4][5] as well as for graphite furnace (GF) analytical techniques [6][7][8][9]. Advantages of the ETV dosing are the capability for solid, liquid, and slurry sampling, reduction of sample preparation time with reduced risk of sample contamination and of analyte loss prior to analysis.…”

“…Up to now, the ETV devices are based on the following designs: (1) cup vaporizers, (2) end-on flow-through GFs with vapor outlet through one of the ends of the graphite tube [2][3][4][5][6][7][8][10][11][12], and (3) upstream configurations with the gas entering the GF through its ends and released upwards through a hole in the tube center [1,9,12,13]. The comparison shows the superiority of the upstream configuration [12].…”

“…Fig. 1 shows the principle and the flow scheme of the axially focusing convection (AFC) upstream ETV device that has become more sophisticated since previous publication, with a copper plate mounted against water-cooled surface as radiation shield, the AFC tube (Duran 50), and introduction unit for graphite boats [9]. The internal flow enters the GF tube through the contact cones and is released through a hole (diameter 2.6-3 mm) in the tube center.…”

Electrothermal atomization of a substance with fractional condensation of the element being determined on a probe

“…The subsequent atomization of the condensate is subjected to interferences to a lesser extent. It was proposed to use different surfaces placed inside a graphite tubular atomizer: a tantalum insert cooled by an argon flow [1-4], a ballast from a roll of refractory wire [5], a graphite platform located over the site of sample dosing [6,7], the upper half of a tubular atomizer with independent heating [8,9], and an additional tubular atomizer with independent heating installed behind the sample evaporator [10][11][12][13][14]. Some interferences decrease due to the FC stage conducted in this way.…”

“…However, up to now none of these methods for decreasing matrix interferences has reached a production level as has, for example, L'vov's platform with a matrix modifier, whose advantages are its simplicity and universality [15]. The FC techniques that are being actively developed at the present time [8][9][10][11][12][13][14] presuppose a considerable complication of the atomizer design. In the present paper, a new technique of FC on a refractory probe [16] that is realized with any tubular atomizer is proposed.…”