Inductively atomic emission spectroscopy

Because light emitted from inductively coupled plasma torches is characteristic of the elements present, the torches were originally introduced for instruments that optically measured the frequencies and intensities of the emitted light and used them, rather than ions, to estimate the amounts and types of elements present (inductively coupled plasma atomic emission spectroscopy. 

To examine a sample by inductively coupled plasma mass spectrometry (ICP/MS) or inductively coupled plasma atomic-emission spectroscopy (ICP/AES) the sample must be transported into the flame of a plasma torch. Once in the flame, sample molecules are literally ripped apart to form ions of their constituent elements. These fragmentation and ionization processes are described in Chapters 6 and 14. To introduce samples into the center of the (plasma) flame, they must be transported there as gases, as finely dispersed droplets of a solution, or as fine particulate matter. The various methods of sample introduction are described here in three parts — A, B, and C Chapters 15, 16, and 17 — to cover gases, solutions (liquids), and solids. Some types of sample inlets are multipurpose and can be used with gases and liquids or with liquids and solids, but others have been designed specifically for only one kind of analysis. However, the principles governing the operation of inlet systems fall into a small number of categories. This chapter discusses specifically substances that are normally liquids at ambient temperatures. This sort of inlet is the commonest in analytical work. 

ICP/AES. inductively coupled plasma and atomic-emission spectroscopy used as a combined technique... 

Inductively coupled plasma atomic emission spectroscopy... 

For inductively coupled plasma atomic emission spectroscopy (ICP-AES) the sample is normally in solution but may be a fine particulate solid or even a gas. If it is a solution, this is nebulized, resulting in a fine spray or aerosol, in flowing argon gas. The aerosol is introduced into a plasma torch, illustrated in Figure 3.21. 

Figure 3.21 A plasma torch for inductively coupled plasma atomic emission spectroscopy...

The classical wet-chemical quaUtative identification of chromium is accompHshed by the intense red-violet color that develops when aqueous Cr(VI) reacts with (5)-diphenylcarba2ide under acidic conditions (95). This test is sensitive to 0.003 ppm Cr, and the reagent is also useful for quantitative analysis of trace quantities of Cr (96). Instmmental quaUtative identification is possible using inductively coupled argon plasma—atomic emission spectroscopy... 

R. K. Winge, V A. Fassel, V. J. Peterson, and M. A. Floyd. Inductively Coupled Plasma Atomic Emission Spectroscopy An Atlas of Spectral Information. Elsevier, Amsrerdam, 1985. ICP-OES specrral scans near emission lines usefol for analysis. 

Inductively coupled plasma with atomic emission spectroscopy (ICP/AES)... 

Catalyst characterization - Characterization of mixed metal oxides was performed by atomic emission spectroscopy with inductively coupled plasma atomisation (ICP-AES) on a CE Instraments Sorptomatic 1990. NH3-TPD was nsed for the characterization of acid site distribntion. SZ (0.3 g) was heated up to 600°C using He (30 ml min ) to remove adsorbed components. Then, the sample was cooled at room temperatnre and satnrated for 2 h with 100 ml min of 8200 ppm NH3 in He as carrier gas. Snbseqnently, the system was flashed with He at a flowrate of 30 ml min for 2 h. The temperatnre was ramped np to 600°C at a rate of 10°C min. A TCD was used to measure the NH3 desorption profile. Textural properties were established from the N2 adsorption isotherm. Snrface area was calcnlated nsing the BET equation and the pore size was calcnlated nsing the BJH method. The resnlts given in Table 33.4 are in good agreement with varions literature data. 

The metal content analysis of the samples was effected by Inductively Coupled Plasma Atomic Emission Spectroscopy (ICP-AES Varian Liberty II Instrument) after microwaves assisted mineralisation in hydrofluoric/hydrochloric acid mixture. Ultraviolet and visible diffuse reflectance spectroscopy (UV-Vis DRS) was carried out in the 200-900 nm range with a Lambda 40 Perkin Elmer spectrophotometer with a BaS04 reflection sphere. HF was used as a reference. Data processing was carried out with Microcal Origin 7.1 software. 

Table 21 reports the ash content and ash composition (determined by inductively coupled plasma-atomic emission spectroscopy, ICP-AES) for all of the calcined cokes used to fabricate the test graphites. It can be seen that the amount of ash and its make-up are variable, but are within the range observed for petroleum-based calcined cokes. Although the ash contents in all of the calcined cokes appear rather high, these materials may still be acceptable because many of the metallic species are driven off during graphitization. This aspect is addressed in the next section. 

Fig. 2. Solid-phase arsenic in ppm versus depth in m from a continuous core. The core consists of clayey silt to depth of 28 m, and fine sand thereafter with a silt horizon at 34 m depth. As was measured by digestion with an HCI-HNO3-H2O aqua regia solution followed by inductively coupled plasma mass spectrometry and inductively coupled plasma atomic emission spectroscopy analysis.

Ponting, M. and Segal, I. (1998). Inductively coupled plasma-atomic emission spectroscopy analyses of Roman military copper alloy artefacts from the excavations at Masada, Israel. Archaeometry 40 109-122. 

FLAA, flame atomic absorption, is termed AAS in most instances in this book and in other places ICP, inductively coupled plasma AES, atomic emission spectroscopy GFAA, graphite furnace atomic absorption ICP-MS, ICP coupled to mass spectroscopy. 

When the problem has been defined and needed background information has been studied, it is time to consider which analytical methods will provide the data you need to solve the problem. In selecting techniques, you can refer back to the other chapters in this book. For example, if you want to measure the three heavy metals (Co, Fe, and Ni) that were suspect in the Bulging Drum Problem, you might immediately think of atomic absorption or inductively coupled plasma atomic emission spectroscopies and reread Chapter 8 of this book. How would you choose between them Which would be more accurate More precise Does your lab have both instruments Are they both in working order What if you have neither of them What sample preparation would be needed ... 

Middleton, W. D. and Price, T. D. (1996). Identification of activity areas by multi-element characterization of sediments from modern and archaeological house floors using inductively coupled plasma-atomic emission spectroscopy. Journal of Archaeological Science 23 673-687. 

NMR) [24], and Fourier transform-infrared (FT-IR) spectroscopy [25] are commonly applied methods. Analysis using mass spectrometric (MS) techniques has been achieved with gas chromatography-mass spectrometry (GC-MS), with chemical ionisation (Cl) often more informative than conventional electron impact (El) ionisation [26]. For the qualitative and quantitative characterisation of silicone polyether copolymers in particular, SEC, NMR, and FT-IR have also been demonstrated as useful and informative methods [22] and the application of high-temperature GC and inductively coupled plasma-atomic emission spectroscopy (ICP-AES) is also described [5]. 

In the inductively coupled plasma atomic emission spectroscopy (ICPAES) method (ASTM DD 5600), a sample of petroleum coke is ashed at 700°C (1292°F) and the ash is fused with lithium borate. The melt is dissolved in dilute hydrochloric acid, and the resulting solution is analyzed by inductively coupled plasma atomic emission spectroscopy using aqueous calibration standards. Because of the need to fuse the ash with lithium borate or other suitable salt, the fusibility of ash may need attention (ASTM D1857). 

In reference 190, the authors describe the spectroscopic and X-ray crystallographic techniques they used to determine the pMMO structure. First, EPR and EX AFS experiments indicated a mononuclear, type 2 Cu(II) center hgated by histidine residues and a copper-containing cluster characterized by a 2.57 A Cu-Cu interaction. A functional iron center was also indicated by Inductively Coupled Plasma-Atomic Emission Spectroscopy (ICP-AES). ICP-AES uses inductively coupled plasma to produce excited atoms that emit electromagnetic radiation at a wavelength characteristic of a particular element. The intensity of this emission is indicative of the concentration of the element (iron in this case) within the sample. 

Chapters 7 and 8 describe two major techniques for the monitoring of trace elements in environmental samples atomic absorption (AA) and inductively coupled plasma-atomic emission spectroscopy (ICP). AA is most ideally suited for analyses where a limited number of trace metal concentrations are needed with high accuracy and precision. ICP has the advantage of multielement analysis with high speed. 

Determination of Trace Inorganic Toxic Substances by Inductively Coupled Plasma-Atomic Emission Spectroscopy... 

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