Optical emissions spectrometer

The chemical compositions of the samples were obtained by ICP in a Varian 715-ES ICP-Optical Emission Spectrometer. Powder X-ray diffraction was performed in a Philips X pert diffractometer using monochromatized CuKa. The crystallinity of the zeolites was obtained from the intensity of the most intense reflection at 23° 20 considering the parent HZ5 sample as 100% crystalline. Textural properties were obtained by nitrogen physisorption at -196°C in a Micromeritics ASAP 2000 equipment. Surface areas were calculated by the B.E.T. approach and the micropore volumes were derived from the corresponding /-plots. Prior to the adsorption measurements the samples were degassed at 400°C and vacuum overnight. 

The instrument which uses this plasma torch is called an inductively coupled plasma atomic emission spectrometer (ICP-AES) or an inductively coupled plasma optical emission spectrometer (ICP-OES). It is similar to an... 

Silva, F.Y., Trevizan, L. C., Silva, C. S., Nogueira, A. R. A., and Nobrega, J. A. (2002). Evaluation of inductively coupled plasma optical emission spectrometers with axially and radially viewed configurations. Spectrochimica Acta B 57 1905-1913. 

Table 1.4 Inductively coupled plasma optical emission spectrometers available on the market... 

More than seventy elements may be detected by standard procedures. Atomic gases, such as O, N, H, He. Ar, Ne, Kr, Xe, and Rn and the halogens are excluded. Nonmetallic substances, such as C, S, and Se. require vacuum path specuometets foi optimum detection and measurement. Analytical ranges may extend from fractional parts per million to about 40% concentration. Computer-controlled photoelectric optical emission spectrometers will output printed percent concentrations for 30 to 50 elements per sample in just a few minutes. This form of analytical instrumentation is used widely in production and quality control, as well as for research studies. 

Optical-Emission Spectrometer. Similar to flame photometer (atomic-absoiption photometer) except that an electric spark rather than a flame is used to vaporize (atomize) unknown samples. 

Induced Coupled Plasma Spectrometry (ICP). An even more sensitive instrument has been developed to detect and quantitate, simultaneously, all inorganic species contained with a sample matrix. One such system is the ICP-OES (optical emission spectrometer) (Figure 25.5). The ICP-OES takes an aliquot of sample that has been acid digested and mixes it with a gas (e.g., argon) forming a plasma (i.e., an ionized gas) that is channeled into a nebulizer. Energy is applied to excite the atoms that are converted by the optics of the instrument into individual wavelengths. The... 

The continuous operation of LCVD could be controlled, in principle, by the strict controls of the flow rate, the system pressure, and the discharge power. The addition of a residual gas analyzer in each pumping system is advantageous in detecting abnormality in gas flow, occurrence of leakage, etc. The addition of more sophisticated diagnostic devices, such as an optical emission spectrometer, in-line XPS, etc., is often counterproductive because the stability of performance and the maintenance requirement cycle of these devices do not match those for the continuous mode operation of LCVD. The information obtainable by these devices... 

Fig. 98. ICP-optical emission spectrometer, (a) gas supply, (b) sampler, (c) peristallic pump, (d) nebulizer, (e) nebulization chamber, (f) hf generator, (g) ICP torch, (h) spectral apparatus, data acquisition, data processing.

Fig. 99. Volatilization of dry solution aliquots from a graphite boat evaporation system coupled to a simultaneous ICP optical emission spectrometer at different heating currents [34],...

Inductively Coupled Plasma-Optical Emission Spectrometer. 84... 

Figure 2.47 Schematic diagram of an inductively coupled plasma-optical emission spectrometer.

At the end of the deposition process some of the support material was stuck to the side of the inner SS cup, while most of the powder (-70-95%) was freely tumbling. In order to collect the powder, the inner SS cup was simply removed and inverted onto a piece of weighing paper. The powder stuck to the side remained in the cup and was not used for the subsequent work. Precious metal loading was determined using a Thermo Jarrell Ash IRIS Inductively Coupled Plasma (ICP) Optical Emission Spectrometer using procedures described previously.[l]... 

Figure 4.10, Schematic diagram of a direct reading optical emission spectrometer. ...

Such large amounts of data can only be sensibly and rapidly analysed and compared with reference spectra using microprocessors such as the fast 32 bit processors in PCs. The main systems in use today are discussed below, and in addition to the above mentioned techniques the microwave induced plasma (MIP) detector, a helium microwave plasma emission source coupled to a GC and an optical emission spectrometer are reviewed. 

Spectrochemical Analysis of Aluminum and Its Alloys by the Point-to-Plane Technique Using an Optical Emission Spectrometer, in Methods for Emission Spectrochemical Analysis, 6th ed., Philadelphia American Society for Testing and Materials, 1971, pp 196-207, ASTM E 227-67. 

GDMS (glow discharge mass spectrometry) is a similar technique to GDOES but GDMS uses a mass spectrometer instead of an optical emission spectrometer. 

A novel technique of atomisation, known as vapour generation via generation of the metal hydride, has been evolved, which has increased the sensitivity and specificity enormously for these elements [5-7]. In these methods the hydride generator is linked to an AAS (flame graphite furnace) or inductively coupled plasma-optical emission spectrometer (ICP-OES) or an inductively coupled plasma mass spectrometer (IPC-MS). Typical detection limits achievable by these techniques range from 3 pg/1 (arsenic) to 0.09 pg/1 (selenium). 

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