@article {747, title = {Linear quadrupoles with added octopole fields}, journal = {Rapid Communications in Mass Spectrometry}, volume = {17}, number = {20}, year = {2003}, note = {ISI Document Delivery No.: 731CTTimes Cited: 21Cited Reference Count: 29}, pages = {2290-2294}, type = {Article}, abstract = {Two methods of adding relatively small octopole fields to the main quadrupole field of quadrupoles and linear ion traps with cylindrical rods are investigated. The first, {\textquoteright}stretching{\textquoteright} the quadrupole by moving two rods out from the axis, produces a combination of higher order fields with similar magnitudes in which the octopole field is not necessarily the greatest. The quadrupole field strength is changed significantly and a large potential appears on the axis. The second method uses rod pairs of different diameters. It adds octopole components of up to several percent while all other higher order fields remain small. An axis potential is also added, but it is only a few percent of the radio-frequency (RF) voltage and approximately equal to the strength of the octopole field. The axis potential can be removed by moving the larger rod pair out from the axis or applying unbalanced RIF to the electrodes. Copyright (C) 2003 John Wiley Sons, Ltd.}, keywords = {EJECTION, FILTER, HARMONICS, MASS-SPECTROMETER, NONLINEAR ION-TRAP, OF-FLIGHT SYSTEM, RESONANCE, SPATIAL, STORAGE-RING}, isbn = {0951-4198}, url = {://000185867500008}, author = {Sudakov, M. and Douglas, D. J.} } @article {4047, title = {Spatial and temporal profiles of indium in a furnace atomization plasma excitation spectrometry source}, journal = {Applied Spectroscopy}, volume = {51}, number = {11}, year = {1997}, note = {ISI Document Delivery No.: YP332Times Cited: 5Cited Reference Count: 39}, month = {Nov}, pages = {1715-1721}, type = {Article}, abstract = {Spatially resolved emission and absorption intensities from the indium 303.93-nm resonance line were measured in a furnace atomization plasma excitation spectrometry (FAPES) source. These measurements show that the spatial structure observed in the analyte emission is due to two effects, The first is the spatial distribution of analyte atoms in the source. The absorption measurements show that this spatial distribution is fairly uniform. There is a slight gradient, with analyte concentrations increasing from the cuvette wall to the center electrode. The fine structure in the emission intensity profiles must therefore be caused by the dependence of the degree of analyte excitation on position within the cuvette. This structure suggests that the FAPES source operates as an atmospheric-pressure radio-frequency glow discharge. Negative glows are seen adjacent to the graphite cuvette wall and center electrode.}, keywords = {ABSORPTION, aluminum, ANALYTE, ATOMIC-ABSORPTION, CCD, DYNAMICS, emission, EMISSION-SPECTROMETRY, FAPES, FURNACE ATOMIZATION PLASMA EXCITATION SPECTROMETRY, GRAPHITE-FURNACE, indium, INVESTIGATING ELECTROTHERMAL ATOMIZATION, LEAD, profile, SPATIAL, SPECTROSCOPY}, isbn = {0003-7028}, url = {://000071266300022}, author = {LeBlanc, C. W. and Blades, M. W.} }