Mass spectrometer manufacturers principle

Although the basic principle of mass spectrometry (MS) was discovered as early as 1910 by Sir J. J. Thomson, it was not untU the end of World War II that MS was first developed for analyses of gas and hydrocarbon mixtures [1], Almost all of the mass spectrometers at that time were made by researchers or specialists. The first commercial mass spectrometer manufactured by Consolidated Engineering Corporation (CEC) was delivered to the Atlantic Refining Company in 1946 for analysis of hydrocarbon fractions in gasoline boiling range [2]. Since then, the petroleum industry has pioneered the use of MS in chemical research. Many advances in MS were driven by the needs of the petroleum industry for analyzing components in complex mixtures. 

GC-C-IRMS was first demonstrated by Matthews and Hayes (1978). However, it was somewhat later that Barrie and others (Barrie et al., 1984) coupled a GC, via a combustion interface, to a dual collector mass spectrometer to produce the forerunner of today s GC-C-IRMS instruments. Even so, true determinations of 815N values of individual compounds by GC-C-IRMS remained elusive until finally demonstrated by Hayes and co-workers (Merritt and Hayes, 1994). More recently the precision of GC-C-IRMS instruments has been improved further still with uncertainties in 813C values as small as 0.5 %o for samples containing 5 pmol C and 0.1 %o for 100 pmol samples having been demonstrated (Merritt and Hayes 1994). Instruments available commercially today, from several manufacturers, all conform to the same general principles of design. 

There are many types of mass spectrometer, each having special design features, some offering very sophisticated modes of analysis and these details will not be described here. Rather, the fundamental principles and instrumental aspects associated with the technique in general are covered. More detailed information is available in specialist books or instrument manufacturers publications. 

In 1989, the Fuji group developed the method for detection of chemical species in the gas phase with use of Li ion attachment to chemical species [11-13]. The principle is based upon a phenomenon that LL ions get attached to chemical species (M) by means of intermolecular association reactions to produce (M + Li)+ adduct ions. Then they are transferred to a mass spectrometer for mass analysis. This approach is exactly the same to cationization for detection of molecular species. Since the potential of Li ion attachment in MS has not yet been reahzed, they attempted to reveal and explore some of the unique properties of Li I AMS. Li ions have been chosen as reactant ions, because the affinity of the species is the highest among all the alkali metal ions. This technique provides mass spectra of quasi-molecular ions formed by lithium ion attachment to the chemical species (M) under high pressure. Results are obtained in the form of trace of LL adduct ions (M + Li)+ (also referred as cationized molecules). The newly developed lAMS [10], manufactured by instmmental maker (Canon Anelva Corp., Japan), exhibits several advantages over conventional mass spectrometers. Currently, ion association MS is available commercially in a various form. Recently, some reviews have been published on the principles, instmmental techniques, unique characteristics, and applications of I AMS [15-20]. 

R 18] [A 1] Each module is equipped with a heater (H3-H8) and a fluidic cooling (C03-C06). Temperature sensors integrated in the modules deliver the sensor signals for the heater control. Fluidic data such as flow and pressure are measured integrally outside the micro structured devices by laboratory-made flow sensors manufactured by silicon machining. The micro structured pressure sensor can tolerate up to 10 bar at 200 °C with a small dead volume of only 0.5 pi. The micro structured mass flow sensor relies on the Coriolis principle and is positioned behind the pumps in Figure 4.59 (FIC). For more detailed information about the product quality it was recommended to use optical flow cells inline with the chemical process combined with an NIR analytic or a Raman spectrometer. 

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