Atomic Absorption AA

AAS = atomic absorption spectroscopy CdS04 = cadmium sulfate GC/ECD = electrochemical gas chromatographic detection GC/FPD = gas chromatography with flame photometric detection HC1 = hydrochloric acid H2S = hydrogen sulfide NaOH = sodium hydroxide NR = not reported PAS = photoacoustic spectroscopy... 

The concentrates were subsequently analysed for arsenic using Varian-Techtron AAS atomic absorption spectrophotometer fitted with a Perkin-Elmer HGA 72 carbon furnace, linked to a zinc reductor column for the generation of arsine (Fig. 5.3). A continuous stream of argon was allowed to flow with the column connected into the inert gas line between the HGA 72 control unit and the inlet to the furnace. Calcium sulfate (10-20 mesh) was used as an adsorbent to prevent water vapour entering the carbon furnace. The carbon tube was of 10 mm id and had a single centrally located inlet hole. 

Figure 5.17. Dual-column ion exchange preconcentration valve. Sa, Sb samples A and B Ca, Cb ion exchange columns A and B Ea, Eb eluant (2 M nitric acid) for columns A and B Wa, Wb waste lines for samples and eluants A and B W waste lines AAS atomic absorption spectrometer. The dimensions of the base plate of the valve are 70 x 45 x 10 mm. See text for details of operation. Source [661]...

AgN03 = silver nitrate CICN = cyanogen chloride CN" = cyanide ion CNATC = cyanides not amenable to chlorination (Rosentreter and Skogerboe 1992) AAS = atomic absorption spectroscopy EPA = Environmental Protection Agency FIA = flow injection analysis GC/ECD = gas chromatograph/electron capture detector HCN = hydrogen cyanide NaOH = sodium hydroxide NIOSH = National Institute for Occupational Safety and Health... 

Table 5.2 Summary of selected analytical methods for molecular environmental geochemistry. AAS Atomic absorption spectroscopy AFM Atomic force microscopy (also known as SFM) CT Computerized tomography EDS Energy dispersive spectrometry. EELS Electron energy loss spectroscopy EM Electron microscopy EPR Electron paramagnetic resonance (also known as ESR) ESR Electron spin resonance (also known as EPR) EXAFS Extended X-ray absorption fine structure FUR Fourier transform infrared FIR-TEM Fligh-resolution transmission electron microscopy ICP-AES Inductively-coupled plasma atomic emission spectrometry ICP-MS Inductively-coupled plasma mass spectrometry. Reproduced by permission of American Geophysical Union. O Day PA (1999) Molecular environmental geochemistry. Rev Geophysics 37 249-274. Copyright 1999 American Geophysical Union...

AAS = atomic absorption spectrometry DTPA = d1ethylenetriaminepentaacetic acid ES = emission spectrometry ... 

AAS = atomic absorption spectrometry HCLO4 = perchloric acid HNO3 = nitric acid H2SO4 = sulfuric acid ICP-AES = inductively coupled plasma-atomic emission spectroscopy Ni = nickel NIOSH = National Institute for Occupational Safety and Health v = volume... 

Analysis. The colorimetric method for In is capable of a detection limit of 20 ppb. Indium or an In compound in the flame gives an indigo blue color (451.1 nm). This photon line allows for the spectrophotometric determination ofinby AAS (atomic absorption flame spectroscopy). The method is sensitive to about 300 ppb. With ETAAS, this limit drops to 10 ppb, as it does with ICPAES. ICPMS drops the limit to 0.01 ppb. Alizarin detects In, as well as Al, but the reaction with Al can be masked by addition of F to a spot test. The limit of detection is about 1 ppm. 

The most frequently applied analytical methods used for characterizing bulk and layered systems (wafers and layers for microelectronics see the example in the schematic on the right-hand side) are summarized in Figure 9.4. Besides mass spectrometric techniques there are a multitude of alternative powerful analytical techniques for characterizing such multi-layered systems. The analytical methods used for determining trace and ultratrace elements in, for example, high purity materials for microelectronic applications include AAS (atomic absorption spectrometry), XRF (X-ray fluorescence analysis), ICP-OES (optical emission spectroscopy with inductively coupled plasma), NAA (neutron activation analysis) and others. For the characterization of layered systems or for the determination of surface contamination, XPS (X-ray photon electron spectroscopy), SEM-EDX (secondary electron microscopy combined with energy disperse X-ray analysis) and... 

POL—Davis differential cathode ray polarography AA—atomic absorption spectroscopy... 

AA—atomic absorption spectrophotometry precision and accuracy estimates in relative %. 

GFAAS = graphite furnace (flameless) atomic absorption spectroscopy MCAAS = micro-cup atomic spectroscopy DCOP-AES = direct current plasma-atomic emission spectroscopy HFP-AES = high frequency piasma-torch-atomic emission spectroscopy NAA - neutron activation analyst-, atomic absorption spectroscopy AAS - atomic absorption spectrophotometer XES = X-ray energy spectrometry and SEM - scanning electron microscopy. 

GFAAS = graphite furnace (flameless) atomic absorption spectroscopy TLC = thin layer chromatography HFP-AES = high frequency plasma-atomic emission spectroscopy NAA = neutron atomic analysis ICP-AES = inductively coupled plasma-atomic emission spectroscopy AAS = atomic absorption spectrometry GSE = graphite spectroscopic electrode UV = ultraviolet spectrophotometry PD = photodensitometer and (3,5-diBr-PADAP) = 2(-3,-5-dibromo-2-pyridylazo)-5- diethyl-ami nophenol. 

AAS = atomic absorption spectroscopy HPLC = high performance liquid chromatography ICP/AES = inductively coupled plasma atomic emission spectroscopy... 

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