Thermal emission mass spectrometry

This research effort has demonstrated the capability of spark source and thermal emission mass spectrometry for determining the fate of trace elements in coal-fired, central power plants. Additionally, isotope dilu-... 

Isotope Dilution By Thermal Emission Mass Spectrometry. A three-stage thermal emission mass spectrometer (TEMS) was used for quantitatively measuring lead and uranium in coal and fly ash and lead in gasoline (Figure 3). The basic design of the instrument is modeled on that developed by White and Collins, 1954 ( 6) and modified at ORNL. The addition of an electrostatic third stage increased the abundance sensitivity to 108 as described by Smith et al. (7). 

Thermal emission mass spectrometry 500 Mg Pb(N03)2 with NH4OH Catanzaro(1967, 1968) Catanzaro et al (1968)... 

Rameback H, Berglund M, Kessel R, Wellum R (2002) Modeling isotope fractionation in thermal ionization mass spectrometry filaments having diffusion controlled emission. Int J Mass Spectrom 216 203-208 Roe JE, Anhar AD, Barling J (2003) Nonhiological fractionation of Fe isotopes evidence of an equilibrium isotope effect. Chem Geol 195 69-85... 

Thermal ionization mass spectrometry (TIMS) is one of the oldest mass spectrometric techniques, first applied by Dempster in 1918.114 The thermal emission of positivly charged ions emitted from a salt on a heated surface was first observed by Gehrcke and Reichenheim 12 years before.115 The thermal surface ionization source is a very simple ion source and operates under high vacuum conditions. TIMS is mostly useful for elements with relatively low ionization energy ( )) - in... 

A number of analytical techniques have been used to determine ppm to ppt levels of vanadium in biological materials. These include neutron activation analysis (NAA), graphite furnace atomic absorption spectrometry (GFAAS), spectrophotometry, isotope dilution thermal ionization-mass spectrometry (IDMS), and inductively coupled plasma atomic emission spectrometry (ICP-AES). Table 6-1 summarizes the analytical methods for determining vanadium in biological materials. 

Nearly every area of measurement science can boast of progress in measuring ever-smaller quantities of chemicals, but several stand out in their stunning trace-analysis capabilities. Trace-metal analysis has come to be dominated by methods that volatilize the sample and then either measure its spectroscopic emission or absorption, or measure the masses of the gaseous metal ions using mass spectrometry. Volatilization is accomplished by various thermal means that include flames, furnaces, and inductively coupled or microwave plasmas. The com-... 

Spark source (SSMS) and thermal emission (TEMS) mass spectrometry are used to determine ppb to ppm quantities of elements in energy sources such as coal, fuel oil, and gasoline. Toxic metals—cadmium, mercury, lead, and zinc— may be determined by SSMS with an estimated precision of 5%, and metals which ionize thermally may be determined by TEMS with an estimated precision of 1% using the isotope dilution technique. An environmental study of the trace element balance from a coal-fired steam plant was done by SSMS using isotope dilution to determine the toxic metals and a general scan technique for 15 other elements using chemically determined iron as an internal standard. In addition, isotope dilution procedures for the analysis of lead in gasoline and uranium in coal and fly ash by TEMS are presented. 

The components in a mixture separate in the column and exit from the column at different times (retention times). As they exit, the detector registers the event and causes the event to be recorded as a peak on the chromatogram. A wide range of detector types are available and include ultraviolet adsorption, refractive index, thermal conductivity, flame ionization, fluorescence, electrochemical, electron capture, thermal energy analyzer, nitrogen-phosphorus. Other less common detectors include infrared, mass spectrometry, nuclear magnetic resonance, atomic absorption, plasma emission. 

K is transformed by emission to Ca. (89.05 %) and by electron capture to " °Ar (10.95 %) [24]. The measurement of activity can be analyzed in environmental samples, after drying and homogenizing, by gamma spectrometry with the use of energy spectrum of 1461 keV. In natural water samples, is measured using the Cherenkov counting technique [25, 26]. Thermal ionization mass spec-... 

Transport phenomena occur particularly when transporting the vapors themselves. They disappear completely when the sample is inserted directly into the signal generation source, where it is evaporated thermally. This approach is known from work with graphite or metal probes in atomic absorption, where for example W wire cups and loops are used. The technique is also used in plasma spectrometry with the inductively coupled plasma (ICP), both in atomic emission [189-191] and in mass spectrometry [192]. Its absolute power of detection is extremely high and the technique can be used both for the analysis of dry solution residues as well as for the volatilization of microamounts of solids. 

Both molecular and atomic detectors have been used in combination with SCF extractors for monitoring purposes. Thus, the techniques used in combination with SFE are infrared spectroscopy, spectrophotometry, fluorescence spectrometry, thermal lens spectrometry, atomic absorption and atomic emission spectroscopies, mass spectrometry, nuclear magnetic resonance spectroscopy, voltammetry, and piezoelectric measurements. 

Argon plasmas are used in optical emission spectrometry (cf. section 14.3.1) to atomize and ionize elements in order to provoke the emission of characteristic spectral lines. Hence, it is not surprising that the same plasma torches are employed to ionize inorganic samples in mass spectrometry. Thermal ionization is induced at high temperatures in a gaseous sample with microwave or an inductively coupled plasma. 

GPC (total radioactive strontium) = beta gas proportional counter Bq = Becquerel dpm = disintegrations per minute EDTA = ethylenediamine tetraacetic acid GFAAS (total strontium) = graphite furnace atomic absorption spectroscopy ICP-AES (total strontium) = inductively coupled plasma atomic emission spectroscopy ICP-MS (isotopic strontium composition) = inductively coupled plasma-mass spectrometry LSC (isotopic quanitification of 89Srand 90Sr) = liquid scintillation counting pCi = pico curies (10-12 curies) PIXE (total strontium) = proton induced x-ray emission TMAH = tetramethylammonium hydroxide TNA (total strontium) = thermal neutron activation and radiometric measurement TRXF (total strontium) = total-reflection x-ray fluorescence... 

GC can achieve the highest resolution of the essential oils, but there are some significant limitations with regards to preparative scale separations. Typically, as the sample capacity is increased, the resolution of the chromatographic separation is reduced. On a lab scale, equipment is available that permits 24-hour automated and unattended separations, however, the recovery yield and sample resolution are still problematic [57]. Capillary column GC has become so routine for essential oil analysis that one rarely finds a lab without that capability. A multitude of detectors exist for GC thermal conductivity (TCD), flame ionization (FID), flame photometric (FPD), thermionic specific (TSD), photoionization (PID), electron capture (ECD), atomic emission (AED), mass spectrometry (MS), and infrared spectroscopy (FTIR) [58,59]. The TCD is used primarily with preparative-GC (packed column) because it is... 

An experimental study has been carried out with peat samples from the forest area of Brunei Darussalam. We should note here that the measurement of emission products requires comprehensive analytical equipment. Hydrocarbons (C1-C4) are determined by gas chromatography with flame ionization detection (GC/FID), CO2 and O2 are analyzed by gas chromatography with thermal conductivity detection (GC/TCD), and CO, by gas chromatography with electron capture detection (GC/ECD). Aldehydes and polynuclear aromatic hydrocarbons (PAHs) are determined by gas chromatography with mass spectrometry (GC/MS). 

The separation of yttrium from the lanthanides is performed by selective oxidation, reduction, fractionated crystallization, or precipitation, ion-exchange and liquid-liquid extraction. Methods for determination include arc spectrography, flame photometry and atomic absorption spectrometry with the nitrous oxide acetylene flame. The latter method improved the detection limits of yttrium in the air, rocks and other components of the natural environment (Deuber and Heim 1991 Welz and Sperling 1999).Other analytical methods useful for sensitive monitoring of trace amounts of yttrium are X-ray emission spectroscopy, mass spectrometry and neutron activation analysis (NAA) the latter method utilizes the large thermal neutron cross-section of yttrium. For high-sensitivity analysis of yttrium, inductively coupled plasma atomic emission spectroscopy (ICP-AES) is especially recommended for solid samples, and inductively coupled plasma mass spectroscopy (ICP-MS) for liquid samples (Reiman and Caritat 1998). 

Electrothermal atomic absorption represents a suitable instrumental technique for the analysis of elements in petroleum products [1-5]. The technique shows very low detection limits, similar to or even better than those found for other spectroscopic techniques, such as Inductively Coupled Plasma Atomic Emission Spectrometry (ICP-AES) [6] and ICP-Mass Spectrometry (ICP-MS) [7-12]. Some problems were evidenced in the use of ETAAS when elements like Ni [3] and Pb [13] are analyzed, due to the different behavior of organo-metallic species during the thermal treatment of standards and samples. 

Shazali 1, Van t Dack L, Gijbels R (1987) Determination of precious metals in ores and rocks by thermal neutron activation/y-spectrometry after preconcentration by nickel sulfide fire assay and coprecipitation with tellurium. Anal Chim Acta 196 49-58 Stembeck J, Sjodin A, Andreasson K (2002) Metal emissions from road traffic and the influence of resuspension—results from two tunnel studies. Atmos Env 36 4735-4744 Sun Y, Guan X, Du A (1998) Determination of platinum group elements by inductively coupled plasma-mass spectrometry combined with nickel sulfide fire assay and tellurium coprecipitation. Spectrochim Acta B 53 1463-1467... 

For the determination of lead concentrations in drinking water, the analytical methods are atomic absorption spectrometry - electro-thermal atomization (AAS-ETA or AAS-fiimace), inductively coupled plasma with detection by atomic emission spectrometry (ICP-AES) or detection by mass spectrometry (ICP-MS). Laboratories are free to use their own chosen analytical techniques. More attention will be required to achieve the necessary analytical accuracy at the lower limit for lead. 

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