Induction-coupled plasma emission spectra

Electron microscopy, X-ray diffraction, inductively coupled plasma emission spectra, and dynamic light-scattering measurements indicated the presence of multidomain spherical particles, containing Ag20, Y203, CuO,... 

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. 

In 1C, the election-detection mode is the one based on conductivity measurements of solutions in which the ionic load of the eluent is low, either due to the use of eluents of low specific conductivity, or due to the chemical suppression of the eluent conductivity achieved by proper devices (see further). Nevertheless, there are applications in which this kind of detection is not applicable, e.g., for species with low specific conductivity or for species (metals) that can precipitate during the classical detection with suppression. Among the techniques that can be used as an alternative to conductometric detection, spectrophotometry, amperometry, and spectroscopy (atomic absorption, AA, atomic emission, AE) or spectrometry (inductively coupled plasma-mass spectrometry, ICP-MS, and MS) are those most widely used. Hence, the wide number of techniques available, together with the improvement of stationary phase technology, makes it possible to widen the spectrum of substances analyzable by 1C and to achieve extremely low detection limits. 

Figure 3. Emission spectra obtained from an induction coupled plasma with an ultrasonic nebulizer (for sample introduction). Aim spectrometer, JACO model with a diffraction grating blazed at 250 nm, and a slit width of 20 pm, was used. The spectral resolution was 10.3 nm/500 channels = 0.0206 nm/channel. (a) Emission spectrum of a 1 pg/l bertjlium, 1% HNOj solution, (b) Emission spectrum of a 1% HN03 blank solution, (c) Difference spectrum obtained by subtracting spectrum (b) from (a). Spectra were obtained after an on-target integration for 8 sec.

Merten D., Broekaert J. A. C. and LeMarchand A. (1999) Spectrum scanning in rapid sequential atomic emission spectrometry with the inductively coupled plasma, Spectro-chim Acta, Part B 54 1377-1382. 

Inductively coupled plasma atomic emission spectrometry (ICP-AES) involves a plasma, usually argon, at temperatures between 6000 and 8000 K as excitation source. The analyte enters the plasma as an aerosol. The droplets are dried, desol-vated, and the matrix is decomposed in the plasma. In the high-temperature region of the plasma, molecular, atomic, and ionic species in various energy states are formed. The emission lines can then be exploited for analytical purposes. Typical detection limits achievable for arsenic with this technique are 30 J,g As/L (23). Due to the rather high detection limit, ICP-AES is not frequently used for the determination of arsenic in biological samples. The use of special nebulizers, such as ultrasonic nebulization, increases the sample transport efficiency from 1-2% (conventional pneumatic nebulizer) to 10-20% and, therefore, improves the detection limits for most elements 10-fold. In addition to the fact that the ultrasonic nebulizer is rather expensive, it was reported to be matrix sensitive (24). Inductively coupled plasma atomic emission spectrometry is known to suffer from interferences due to the rather complex emission spectrum consisting of atomic as... 

There are different spectrophotometric techniques for analysis of contaminants in biofuels. Simultaneous detection of the absorption spectrum and refractive index ratio with a spectrophotometer for monitoring contaminants in bioethanol has been carried out by Kontturi et al., 2011. Inductively Coupled Plasma Atomic Emission Spectrometry and optical emission spectral analysis with inductively coupled plasma (ICP-OES) have also been used to analyze biodiesel samples for trace metals (ASTM, 2007 ECS, 2006). An ICP-MS instrument fitted with an octopole reaction system (ORS) was used to directly measure the inorganic contents of several biofuel materials. Following sample prepwation by simple... 

The chemical composition of the natural beryl sample used in this study was analyzed by X-ray wavelength dispersive spectroscopy for major atomic contents, inductivity coupled plasma-atomic emission spectroscopy for Be content, and atomic absorption sp>ectroscopy for Li and Rb contents (Table 1). The type I/II H2O contents were determined from intensities of IR bands due to the asymmetric stretching of type I and the symmetric stretching of type II in a polarized IR spectrum at RT (See the spectrum in the next section), using their molar absorption coefficients of 206 L moH cm-i and 256 L moH cm-i. 

ICP-AES Induct. Coupled Plasma-Atomic Emission Spectroscopy Atomize (flame, electro, thermal, ICP, etc.) Emission spectrum Conceniralion of alomic species (guanlilalive, using slandards) 3... 

The optics are aligned with the base of the plume where atomic relaxation is most prevalent. The emitted radiation from the ICP torch is focused into the monochromator and detected by a photomultiplier tube (PMT) or polychro-mator detector. The output is then processed and displayed under computer control as the inductively coupled plasma-atomic emission spectrum (ICP-AES). 

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