Spectrometer for simultaneous

G. M. Levy, A. Quaglia, R, E. Lazure, and S. W. McGeorge. Spect. Acta. 42B, 341, 1987. Describes the diode array-based spectrally segmented spectrometer for simultaneous multielement analysis. 

N. Jakubowski, D. Stuewer and W. Vieth, Performance of a glow discharge mass spectrometer for simultaneous multielement analysis of steel, Anal. Chem., 59 (1987) 1825-1830. 

FIG. 1. Electronic circuit for adapting the - C probe of the Varian XL-IOO-15 spectrometer for simultaneous H and "B decoupling at 100 and 32 MFlz respectively. By altering the component values other frequencies can be accommodated. From ref. 76. 

MIO. Mavrodineanu, R., and Hughes, R. C., A multichannel spectrometer for simultaneous atomic absorption and flame emission analysis. Appl. Opt. 7, 1281-1285 (1968). 

The objective of this work is to simulate an industrial process on a bench scale, allowing a wide spectrum of operation conditions and measurements. Taking into account the complexity of the process as well as the fact that the calorimetric signal reflects the sum of physicochemical changes in the reaction system, an additional on-line mini-spectrometer (OceanOptics, S2000 spectrometer) for simultaneous in situ measurements as well as some off-line data furnished by TMDSC and gravimetric measurements have been used. 

XRD has also been coupled with DSC. An instrument based on a conventional X-ray source was described by Newman et al. that was used to study catalyst regeneration. This instrument incorporated a mass spectrometer for simultaneous EGA. A series of XRD spectra taken during the reduction of the spent catalysts is shown in Figure 12, and reveals the intermediate product copper(i) oxide, before final reduction to copper itself. 

Several instrument manufacturers offer echelle-lype spectrometers for simultaneous determination of a multitude of elements by atomic emission spectroscopy. The optical designs of two of these instruments are shown in Figures 10-7,10-9, and 10-11. 

Brenner 1. B., Vats S. and Zander A. T. (1999) A new CCD axially viewed ICP atomic emission spectrometer for simultaneous multi-element geoanalysis. Determination of major and minor elements in silicate rocks,... 

Since modern FTIR spectrometers can operate in a rapid scan mode with approximately 50 ms time resolution, TRIR experiments in the millisecond time regime are readily available. Recent advances in ultra-rapid scanning FTIR spectroscopy have improved the obtainable time resolution to 5 ms. Alternatively, experiments can be performed at time resolutions on the order of 1-10 ms with the planar array IR technique, which utilizes a spectrograph for wavelength dispersion and an IR focal plane detector for simultaneous detection of multiple wavelengths. ... 

For non-simultaneously operating multi-sources it is necessary to check whether the data quality achieved is sufficient, especially for fast LC systems with very narrow peaks. A switching source splits the available acquisition time for the offered ionization types and therefore reduces the true acquisition rate of the mass spectrometer. However, simultaneously operating sources do not explicitly show which compound ionized with what technique. If this information is really necessary, two separate runs must be performed. 

Yang, L. et al. 2001. Evaluation of a four-channel multiplexed electrospray triple quadrupole mass spectrometer for the simultaneous validation of LC/MS/MS methods in four different preclinical matrixes. Anal. Chem. 73 1740. 

Temperature programmed sulfidation or temperature programmed reaction spectroscopy usually deal with more than one reactant or product gas. In these cases a TCD detector is inadequate and one needs a mass spectrometer for the detection of all reaction products. With such equipment one obtains a much more complete picture of the reaction process, because one measures simultaneously the consumption of reactants and the formation of products. 

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. 

Cornish, T.J. Cotter, R.J. A Curved Field Reflection TOF Mass Spectrometer for the Simultaneous Focusing of Metastable Product Ions. Rapid Commun. Mass Spectrom. 1994, 8. 781-785. 

Other desirable features of a monochromator are stability and multi-element capabUity. Initially, direct reading spectrometers, based on a polychromator, were used for simultaneous multi-element analysis, although these were expensive, bulky and generally limited to specific elements. The development of rapid-scanning monochromators under... 

Figure 1.2 Principle of the operation of a mass spectrometer including sample introduction system, ion source, mass separator (e.g., a magnetic sector field) and ion detector system (e.g., double ion collectors for simultaneous measurements of two separated ion beams).

In 1977, Jochum et aZ.12,14 developed the multiple ion counting (MC) technique using an old spark source mass spectrometer with 20 separate channeltrons 1.8 mm wide for simultaneous electrical ion detection. The sensitivity was increased by a factor of 20 compared to SSMS with ion detection using a photoplate and the precision of the analytical results was improved. 

A direct mass spectrometric method for simultaneous detection of five benzimidazoles including levamisole, thiabendazole, mebendazole, fenbendazole, and febantel in sheep milk was reported (377). The method, which involves injection of crude milk extracts and selection and collision of the most abundant ionic species obtained under electron impact ionization, was highly sensitive and rapid. Another direct mass spectrometric approach for rapid and quantitative determination of phenothiazine in milk was also described (323). This method involves an extraction step using a Cig microcolumn disc, followed by thermal desorption of the analyte from the disc directly into an ion trap mass spectrometer. 

The HREELS, Auger electron spectroscopy (AES) and thermal desorption spectrometry (TDS) experiments were carried out in a UHV chamber described previously.6 Briefly, the chamber was equipped with a HREELS spectrometer for vibrational analysis, a single-pass cylindrical mirror analyzer for AES measurements and a quadrupole mass spectrometer for TDS measurements. The HREELS spectra were collected in the specular direction with an incident energy of 3.5 eV and with a spectroscopic resolution of 50-80 cm-1. The TDS data were obtained by simultaneously monitoring up to 16 masses, with a typical heating rate of about 1.5 K s-1. 

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