History spectrometry

Chemical analysis of the metal can serve various purposes. For the determination of the metal-alloy composition, a variety of techniques has been used. In the past, wet-chemical analysis was often employed, but the significant size of the sample needed was a primary drawback. Nondestmctive, energy-dispersive x-ray fluorescence spectrometry is often used when no high precision is needed. However, this technique only allows a surface analysis, and significant surface phenomena such as preferential enrichments and depletions, which often occur in objects having a burial history, can cause serious errors. For more precise quantitative analyses samples have to be removed from below the surface to be analyzed by means of atomic absorption (82), spectrographic techniques (78,83), etc. 

Benzo[c]furan, 1,3-dihydro-1,3-diphenyl-mass spectrometry, 4, 585 Benzo[c]furan, 1,3-dfmethyl-synthesis, 4, 699, 701 Benzo[c]furan, 1,3-diphenyl-cycloaddition reactions, 4, 67 electrophilic substitution, 4, 604 history, 4, 533... 

A History of Mass Spectrometry http //masspec.scripps.edu/information/history/... 

Many books deal with general mass spectrometry [6-10]. In recent mass spectrometry books, little specific attention has been paid to polymer additives. De Hoffmann and Stroobant [11] and others [12] have traced the history of mass spectrometry. 

Electrospray (ES) existed long before its application to mass spectrometry (MS). It is a method of considerable importance for the electrostatic dispersion of liquids and creation of aerosols. The interesting history and notable research advances in that field are very well described in Bailey s book Electrostatic Spraying of Liquids. 37 Much of the theory concerning the mechanism of the charged droplet formation was developed by researchers in this area. The latest works can be found in a special issue38 of the Journal of Aerosol Science devoted to ES. 

M. Regert, Investigating the history of prehistoric glues through gas chromatography mass spectrometry, Journal of Separation Science, 27, 244 254 (2004). 

R. White and J. Kirby, Preliminary research into lac lake pigments using HPLC/electrospray mass spectrometry, Dyes in History and Archaeology, 16/17, 167 178 (2001). 

The 6180 in Byrd core melted ice as a function of depth has been measured by mass spectrometry [4,5]. Since the 6180 scale depends on the temperature of the ocean water that developed into snow flakes [6], accurate dating of the core itself is necessary to reveal the temperature history of the ocean surface water. Oeschger et al., [7] measured the 14C contents of C02 extracted from 3 tons of ice melted i n situ, at depths of 100, 175, 270, and 380 m near the Byrd site, their 14C ages for 270- and 380-m depths are 1300 700 and 3000 500 years, respectively. 

The first part of this book is dedicated to a discussion of mass spectrometry (MS) instrumentation. We start with a list of basic definitions and explanations (Chapter 1). Chapter 2 is devoted to the mass spectrometer and its building blocks. In this chapter we describe in relative detail the most common ion sources, mass analyzers, and detectors. Some of the techniques are not extensively used today, but they are often cited in the MS literature, and are important contributions to the history of MS instrumentation. In Chapter 3 we describe both different fragmentation methods and several typical tandem MS analyzer configurations. Chapter 4 is somewhat of an outsider. Separation methods is certainly too vast a topic to do full justice in less than twenty pages. However, some separation methods are used in such close alliance with MS that the two techniques are always referred to as one combined analytical tool, for example, GC-MS and LC-MS. In effect, it is almost impossible to study the MS literature without coming across at least one separation method. Our main goal with Chapter 4 is, therefore, to facilitate an introduction to the MS literature for the reader by providing a short summary of the basic principles of some of the most common separation methods that have been used in conjunction with mass spectrometry. 

No tandem MS experiment can be successful if the precursor ions fail to fragment (at the right time and place). The ion activation step is crucial to the experiment and ultimately defines what types of products result. Hence, the ion activation method that is appropriate for a specific application depends on the MS instrument configuration as well as on the analyzed compounds and the structural information that is wanted. Various, more or less complementary, ion activation methods have been developed during the history of tandem MS. Below we give brief descriptions of several of these approaches. A more detailed description of peptide fragmentation mles and nomenclature is provided in Chapter 2. An excellent review of ion activation methods for tandem mass spectrometry is written by Sleno and Volmer, see Reference 12, and for a more detailed review on slow heating methods in tandem MS, see Reference 13. 

Gas-source mass spectrometry. Work on Se stable isotopes has a long history, dating back to the Ph.D. work of H. Roy Krouse around 1960. From 1960 to 1990, analyses were done by gas-source mass spectrometry using SeF (Krouse and Thode 1962). The sample Se was converted to Se(0), then reacted with Fj gas to produce SeF. This method required large quantities (e.g., tens of micrograms) of Se for measurements and thus was not widely applied. Recent continuous flow mass spectrometry methods could enable gas-source measurements on much smaller quantities, but will still use too much sample to compete with TIMS and MC-ICP-MS methods. 

R.B. Cody, Electrospray ionization mass spectrometry History, theory, and instrumentation. In B.N. Pramanik, A.K. Ganguly, M.L. Gross (Eds.) Applied Electrospray Mass Spectrometry, Marcel Dekker, Inc., New York, 2002, pp. 1-104. 

---