Emission spectrometers

Schematic diagram of an argon plasma emission spectrometer.

Schematic diagram of a muitichannei atomic emission spectrometer, showing the arrangement of muitipie exit siits and detectors for the simuitaneous anaiysis of severai eiements.

M. D. Hester, Gas Plasma Analysis Using an Emission Spectrometer, AUiedSignal Inc., Kansas City, Mo., Jan. 1990, p. KCP-613-4169. 

Recently it has been shown that rotating coiled columns (RCC) can be successfully applied to the dynamic (flow-through) fractionation of HM in soils and sediments [1]. Since the flow rate of the extracting reagents in the RCC equipment is very similar to the sampling rate that is used in the pneumatic nebulization in inductively coupled plasma atomic emission spectrometer (ICP-AES), on-line coupling of these devices without any additional system seems to be possible. 

Diphenylcarbazide as adsorption indicator, 358 as colorimetric reagent, 687 Diphenylthiocarbazone see Dithizone Direct reading emission spectrometer 775 Dispensers (liquid) 84 Displacement titrations 278 borate ion with a strong acid, 278 carbonate ion with a strong acid, 278 choice of indicators for, 279, 280 Dissociation (ionisation) constant 23, 31 calculations involving, 34 D. of for a complex ion, (v) 602 for an indicator, (s) 718 of polyprotic acids, 33 values for acids and bases in water, (T) 832 true or thermodynamic, 23 Distribution coefficient 162, 195 and per cent extraction, 165 Distribution ratio 162 Dithiol 693, 695, 697 Dithizone 171, 178... 

Thermal Emission Spectrometer) instrument indicated the metallic nature of the rock [340]. Observations made with the panoramic camera and the microscopic image revealed that the surface of the rock is covered with pits interpreted as regmaglypts and indicate the presence of a coating on the surface. The a-Particle-X-ray spectrometer (APXS) and the Mossbauer spectrometer were used to investigate the undisturbed and the brushed surface of the rock. Based on the Ni and Ge... 

Table 8.29 shows the main characteristics of ICP-AES as a fast multi-element technique. Analytical figures of merit for ICP emission spectrometers are... 

At a terminal voltage of 4 V and a frequency of 300 Hz the anion Tb(TTFA) shows a very weak eel. It was identified by a broad-band interference filter to appear around 565 nm. The intensity was too low to record the eel spectrum on the emission spectrometer. 

The chemical composition of the samples was determined using an inductively Coupled plasma atomic emission spectrometer (ICP-AES) JY 38 from Jobin Yvon. Specific surface area values were determined by BET method using a Micromeritics Instrument Corp. FlowSorb 2300. The basicity of the materials was studied by temperature programmed desorption (TPD) of C02 used as a probe molecule. The equipment was described in a previous work [7]. FTIR spectra of pellets pressed at 2.5xl08 Pa were recorded with a Vector 22 spectrometer from Brucker. The samples were diluted with KBr (lOOmg KBr - 1.5mg of the sample). 

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 application of the Spectroscan DC plasma emission spectrometer confirmed that for the determination of cadmium, chromium, copper, lead, nickel, and zinc in seawater the method was not sufficiently sensitive, as its detection limits just approach the levels found in seawater [731]. High concentrations of calcium and magnesium increased both the background and elemental line emission intensities. 

Nygaard [752] has evaluated the application of the Spectraspan DC plasma emission spectrometer as an analysis tool for the determination of trace heavy metals in seawater. Sodium, calcium, and magnesium in seawater are shown to increase both the background and elemental line emission intensities. Optimum analytical emission lines and detection limits for seven elements are reported in Table 5.8. 

An increase in specificity, permitting a lesser concern with clean-up procedures, can be gained by using a microwave emission spectrometer as the... 

Francesconi, K.A., P. Micks, R.A. Stockton, and K.J. Irgolic. 1985. Quantitative determination of arsenobe-taine, the major water-soluble arsenical in three species of crab, using high pressure liquid chromatography and an inductively coupled argon plasma emission spectrometer as the arsenic-specific detector. Chemosphere 14 1443-1453. 

Emission spectrometer incorporating sample and counter electrodes, means of excitation, prism or grating monochromator, photomultiplier detection system, microprocessors or computers for data processing, interference correction and data display. 

A diagram of an emission spectrometer is shown in Figure 8.3. The electric discharge occurs between a pair of electrodes (preferably enclosed in a special housing for reasons of safety) one of which contains the sample. Emitted radiation is dispersed by a prism or grating monochromator and detected by photomultipliers. 

Glow discharge lamp (analogous to hollow cathode lamp) in which the sample acts as the cathode. Attached to a standard atomic emission spectrometer. 

Emission spectrometer incorporating a sample nebulizer, grating monochromator, photomultiplier detection system and microprocessor controller. Excitation by dc-arc plasma jet, or inductively coupled plasma. Laser excitation sometimes used. 

The outline of the construction of a typical plasma emission spectrometer is to be seen in Figure 8.10. The example shown has an inductively coupled plasma, excitation source, but the outline would be similar were a dc source to be fitted. Different combinations of prisms and diffraction gratings may be used in the dispersion of the emitted radiation, and in the presentation of the analytical signal. Instruments are computerized in operation and make use of automatic sample handling. Sophisticated data handling packages are employed routinely to deal with interferences, and to provide for clarity in data output. 

The APXS and MB in-situ dataset from individual stratigraphic units can be placed in a geologic context when reconciled with the MER remote sensing Miniature Thermal Emission Spectrometer (Mini-TES McSween et al. 2008) and Panoramic Camera (e.g. Farrand et al. 

Selecting an approach A nearby lab specializes in mass spectrometric analysis and can perform the EPA screening method for pesticides and other toxic chemicals. Your own lab just bought an inductively coupled plasma emission spectrometer and can analyze the water for heavy metals. 

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. 

The current generation of inductively coupled plasma emission spectrometers provide limits of detection in the range of 0.1-500pg L 1 in solution, a substantial degree of freedom from interferences and a capability for simultaneous multi-element determination facilitated by a directly proportional response between the signal and the concentration of the analyte over a range of about five orders of magnitude. 

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

These workers used an ARC 34000 inductively coupled plasma emission spectrometer with flow-injection hydride generation. The 189.04nm line (3nd order) was used for arsenic measurement. The flow-injection block and Buckler peristaltic pump, as described by Liversage et al. [125] were also used for the determination of arsenic by hydride generation. 

Detailed operating conditions for the inductively coupled plasma emission spectrometer have been described by Brzezinska et al. [126]. 

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