Inductively coupled plasma analysis

Table 5.1 Inductively coupled plasma analysis of Heck reaction filtrates. (Reproduced from ref. 13, with permission.)...

Atomic absorption spectroscopy is commonly used to determine Fe, Al, Mn, Cr and other metals. Standard solutions should be prepared with the same acid concentration as that of the test solutions. Apart from Al which requires a nitrous oxide/acetylene flame, these cations may be measured using an air/acetylene flame. These metals may also be measured by inductive coupled plasma analysis (ICP). 

Table 1. Chemical analysis of the as-extruded alloys. Concentrations (in atomic percent) were determined by inductively coupled plasma analysis. Sulfur, oxygen and nitrogen contents were determined by combustion analysis.

X-ray Fluorescence Spectrometry and Inductively Coupled Plasma analysis reveal the presence in the zircons of all existing REE. The steady-state luminescence in natural zircons is dominated by broad emission arising from radiation-induced centers and narrow emission lines of Dy " (Trofimov 1962 Tarashchan 1978). These emissions obscure the spectra of other REE. The thermal treatment enables to solve this problem in certain cases using the fact that the intensity of broad band luminescence quickly decreases after heating at 700 °C-800 °C, while the intensities of the REE lines remain nearly constant (Shinno 1986, 1987). Even after heating the samples not all the REE can be identified by steady-state spectroscopy since the weaker luminescence lines of certain REE are obscured by stronger luminescence of others. For example, luminescence of Pr " is difficult to... 

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. 

Wangzhao, Z., Advanced Inductively Coupled Plasma Mass Spectrometry Analysis of Rare Elements, Balkema Publishers, 1999. 

Nickel also is deterrnined by a volumetric method employing ethylenediaminetetraacetic acid as a titrant. Inductively coupled plasma (ICP) is preferred to determine very low nickel values (see Trace AND RESIDUE ANALYSIS). The classical gravimetric method employing dimethylglyoxime to precipitate nickel as a red complex is used as a precise analytical technique (122). A colorimetric method employing dimethylglyoxime also is available. The classical method of electro deposition is a commonly employed technique to separate nickel in the presence of other metals, notably copper (qv). It is also used to estabhsh caUbration criteria for the spectrophotometric methods. X-ray diffraction often is used to identify nickel in crystalline form. 

Spectroscopic methods for the deterrnination of impurities in niobium include the older arc and spark emission procedures (53) along with newer inductively coupled plasma source optical emission methods (54). Some work has been done using inductively coupled mass spectroscopy to determine impurities in niobium (55,56). X-ray fluorescence analysis, a widely used method for niobium analysis, is used for routine work by niobium concentrates producers (57,58). Paying careful attention to matrix effects, precision and accuracy of x-ray fluorescence analyses are at least equal to those of the gravimetric and ion-exchange methods. 

Rubidium metal is commeicially available in essentially two grades, 99 + % and 99.9 + %. The main impurities ate other alkali metals. Rubidium compounds are available in a variety of grades from 99% to 99.99 + %. Manufacturers and suppliers of mbidium metal and mbidium compounds usually supply a complete certificate of analysis upon request. Analyses of metal impurities in mbidium compounds are determined by atomic absorption or inductive coupled plasma spectroscopy (icp). Other metallic impurities, such as sodium and potassium, are determined by atomic absorption or emission spectrograph. For analysis, mbidium metal is converted to a compound such as mbidium chloride. 

Numerous methods have been pubUshed for the determination of trace amounts of tellurium (33—42). Instmmental analytical methods (qv) used to determine trace amounts of tellurium include atomic absorption spectrometry, flame, graphite furnace, and hydride generation inductively coupled argon plasma optical emission spectrometry inductively coupled plasma mass spectrometry neutron activation analysis and spectrophotometry (see Mass spectrometry Spectroscopy, optical). Other instmmental methods include polarography, potentiometry, emission spectroscopy, x-ray diffraction, and x-ray fluorescence. 

The complex of the following destmctive and nondestmctive analytical methods was used for studying the composition of sponges inductively coupled plasma mass-spectrometry (ICP-MS), X-ray fluorescence (XRF), electron probe microanalysis (EPMA), and atomic absorption spectrometry (AAS). Techniques of sample preparation were developed for each method and their metrological characteristics were defined. Relative standard deviations for all the elements did not exceed 0.25 within detection limit. The accuracy of techniques elaborated was checked with the method of additions and control methods of analysis. 

The most common detectors in HPLC are ultraviolet, fluorescence, electrochemical detector and diffractometer. However, despite all improvements of these techniques it seems necessary to have a more selectivity and sensitivity detector for the purposes of the medical analysis. It should be therefore improvements to couple analytical techniques like infrared IR, MS, nuclear magnetic resonance (NMR), inductively coupled plasma-MS (ICP-MS) or biospecific detectors to the LC-system and many efforts have been made in this field. 

Laser based mass spectrometric methods, such as laser ionization (LIMS) and laser ablation in combination with inductively coupled plasma mass spectrometry (LA-ICP-MS) are powerful analytical techniques for survey analysis of solid substances. To realize the analytical performances methods for the direct trace analysis of synthetic and natural crystals modification of a traditional analytical technique was necessary and suitable standard reference materials (SRM) were required. Recent developments allowed extending the range of analytical applications of LIMS and LA-ICP-MS will be presented and discussed. For example ... 

In Inductively Coupled Plasma-Optical Emission Spectroscopy (ICP-OES), a gaseous, solid (as fine particles), or liquid (as an aerosol) sample is directed into the center of a gaseous plasma. The sample is vaporized, atomized, and partially ionized in the plasma. Atoms and ions are excited and emit light at characteristic wavelengths in the ultraviolet or visible region of the spectrum. The emission line intensities are proportional to the concentration of each element in the sample. A grating spectrometer is used for either simultaneous or sequential multielement analysis. The concentration of each element is determined from measured intensities via calibration with standards. 

Inductively Coupled Plasma-Optical (ICP-optical) methods and ICPMS are extremely sensitive elemental survey techniques that also are described in this volume. ICP methods, however, require a solution for analysis, so that the direct... 

The inductively coupled plasma and the torch used in ICPMS are similar to that used in ICP-OES. In ICPMS, the torch is aimed horizontally at the mass spectrometer, rather than vertically, as in ICP-OES. In ICPMS the ions must be transported physically into the mass spectrometer for analysis, while in ICP-OES light is trans-... 

The Inductively Coupled Plasma (ICP) has become the most popular source for multielement analysis via optical spectroscopy since the introduction of the first commercial instruments in 1974. About 6000 ICP-Optical Emission Spectrometry (ICP-OES) instruments are in operation throughout the world. 

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