Acronyms instrumental techniques

In-situ Fourier transform infrared spectroscopy. The final technique in this section concerns the FTIR approach which is based quite simply on the far greater throughput and speed of an FTIR spectrometer compared to a dispersive instrument. In situ FTIR has several acronyms depending on the exact method used. In general, as in the EMIRS technique, the FTIR-... 

A description of the many techniques, procedures and instrumentation used in gas-phase ion investigations is beyond the scope of this chapter and the interested reader is referred to the original works cited in the text. A few words are spent, however, on the most recent and less common ones. The acronyms currently used to refer to the various techniques and apparatus are also adopted here. A list of all abbreviations recurring in this chapter has been included above. 

An extensive list that defines acronyms and abbreviations in the field of mass spectrometry was published in 2002 [6], A single analytical technique or a type of instrument is abbreviated without hyphens or slashes. However, it is customary to use hyphens for a description of an instrument whereas an abbreviation that describes the method uses slashes. For example, LC-MS is an instrument where a liquid chromatograph is coupled with a mass spectrometer, while LC/MS is the method of liquid chromatography/mass spectrometry. Thus, one uses an LC-MS instrument to obtain a LC/MS spectrum. 

The final example of our applications engineering activity is a portable, hand-held X-ray instrument developed at the Goddard Space Flight Center. This device which is called a Lixiscope (an acronym for Low Intensity X-ray Imaging Scope) resulted from our work on X-ray and gamma-ray spectroscopic techniques for astrophysical and planetary observations. 

Where relevant it is usual for an acronym to be used for both the technique and the instrument, e.g. MS for Mass Spectrometry and Mass Spectrometer. The context of use should always be considered. 

Several instruments have been developed for measuring kinetics at temperatures below that of liquid nitrogen [M]- Liquid helium cooled drift tubes and ion traps have been employed, but this apparatus is of limited use since most gases freeze at temperatures below about 80 K. Molecules can be maintained in the gas phase at low temperatures in a free jet expansion. The CRESU apparatus (acronym for the French translation of reaction kinetics at supersonic conditions) uses a Laval nozzle expansion to obtain temperatures of 8-160 K. The merged ion beam and molecular beam apparatus are described above. These techniques have provided important information on reactions pertinent to interstellar-cloud chemistry as well as the temperature dependence of reactions in a regime not otherwise accessible. In particular, information on ion-molecule collision rates as a function of temperature has proven valuable in refining theoretical calculations. 

There are around a dozen GC detectors in common use. Detailed descriptions and illustrations of 16 dilferent types, together with representative application chromatograms, can be accessed at the www.srigc.com site fisted in Appendix 12.1. Spectroscopic instruments can be interfaced to the effluent of a GC and act as a form of detector which has the compound identification power of a spectroscopic measurement. This mating of a separation instrument to a spectroscopic instmment is called a hyphenated technique. The acronyms for the two classes of instruments are separated by a hyphen [or sometimes a slash (/)], as in GC-MS gas chromatography-mass spectrometry. These will be discussed later in Section 12.8. Some of the general characteristics of GC detectors which need to be considered are the following ... 

This chapter summarizes the principles of some of the many spectroscopic techniques that are available for the analysis or study of aspects of adhesive bonding science and technology. As indicated in Table 1, there are dozens of techniques and new acronyms appear almost on a daily basis. The number of instrumental spectroscopies available today to the scientist is bewildering, especially the many techniques for surface characterization. Therefore, it is likely that some techniques have been missed, although it was attempted to cover them all, at least in Table 1. The choice of techniques from that listing that were actually discussed in this chapter had to be limited and was in some cases somewhat arbitrary and subjective. However, some emphasis was put on techniques that can be used in the study of the science of adhesive bonding technology. Techniques for routine analysis, e.g., NMR or the various mass spectrometries, were not discussed in depth. 

This section deals with some general principles of tandem mass spectrometry and its applicability to quantitative analysis. The MS/MS acronym is used in this book as a general term for aU tandem mass spectrometry techniques. More detailed descriptions of how the principles are exploited in practice for the various instrumental types are given in later sections of this chapter. The general concept of tandem mass spectrometry in qualitative (structural) analysis is that additional chemical information, over and above that contained in a conventional onedimensional mass spectrum, can be obtained by examining the connectivity relationships among some or all of the ions in that mass spectrum. The connectivities arise as a result of the dissociation reactions that lead to the fragment ions in a mass spectrum, e.g. ... 

In this chapter, two areas are considered where the unique properties of microelectrodes have had a significant impact (i) the use of microelectrodes and arrays of microelectrodes in electroanalytical studies (in foodstuffs, in concentrated industrial solutions, analysis with minimal sample preparation), especially in combination with pulsed amperometric techniques and (ii) in scanning electrochemical microscopy (SECM note that the acronym is used for both the instrument and the technique). 

The acronym NIRA, or near-infrared analysis, is a term that implies the use of computer algorithms and multivariate data-handling techniques to provide either qualitative or quantitative analysis of a sample (or samples). NIRS includes a single spectral measurement and as such is a more generic definition. For example, an optical engineer involved in the design of a MR instrument would be involved with NIRS but not necessarily NIRA. 

The earliest forms of SECM experiments were carried out in the potentiometric mode. Evans reported how he used a traveling reference electrode to map equipotential surfaces in solution and calculate corrosion rates on a water pipeline. Isaacs and coworkers revived the idea in 1972 and coined the acronym SRET for scanning reference electrode technique. Instruments used to be homemade, often with rudimentary traveling devices such as the arm of an X-Y recorder and the spatial resolution was at best submillimeter. A computer-controlled instrument was commercially produced by Uniscan Instruments with a spatial resolution around 20 pm. The SRET has now been superseded by the scanning vibrating electrode technique, known as SVET, which achieves higher spatial resolution and improved sensitivity. A SVET manufactured by Uniscan Instruments is now commercially available from Uniscan Instruments and Princeton Applied Research. 

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