Nier mass spectrometer

The hydrogen-deuterium ratios were analyzed in the Consolidated Nier Mass spectrometer, while the hydrocarbons were analyzed in a General Electric Mass Spectrometer. The intensities for the various masses were converted into isotopic molecular composition using the procedure previously outlined (9). 

Fig. 1. Schematic diagram of a double-focusing Nier-Johnson magnetic sector mass spectrometer where ( " ) represents paths of ions having slightly...

The reactions were studied with a 6-inch 60°-sector mass spectrometer. The ion source is of the Nier type (11), machined from a block of... 

A. O. Nier. A Mass Spectrometer for Routine Isotope Abundance Measurements. Rev. Sci. Instrum., 11(1940) 212-216. 

Mass spectrometry is one of the oldest instrumental analytical methods. Positive rays were discovered by Goldstein in 1886 (after Barrie Prosser, 2000). The first mass spectrometer for routine measurements of stable isotope abundances was reported in 1940 and improved upon over the following ten years Nier, 1940, Nier, 1947, Murphey, 1947, McKinney et al, 1950, after Prosser, 1993. It is remarkable that the vast majority of active gas spectrometers in use today are little changed from those described around 50 years ago. For most people, mass spectrometry now means organic molecular structure determination. However, within the last 15... 

In 1935 A.O. Nier designed a relatively simple but accurate mass spectrometer employing the principle of double focussing. The essential features are the same as described above but some improvements have been made which are ... 

As the name implies, the sample is introduced into the mass spectrometer as a gas (Nier 1940). There are two types of sources, the classic viscous flow source and the continuous flow source. The viscous flow source typically consists of two identical inlet systems that are coupled to the mass spectrometer by a change-over valve, which allows rapid switching for comparison of isotope ratios measured for sample and standard gases. In the continuous flow source, samples gas is introduced as a bubble in a non-reactive carrier gas stream. 

In Inductively Coupled Plasma Mass Spectrometry. Montaser A (ed) Wiley-VCH, New York, p 83-264 Montaser A, Zhang H (1998) Mass spectrometry with mixed-gas and Helium ICPS. In Inductively Coupled Plasma Mass Spectrometry. Montaser A (ed), Wiley-VCH, New York, p 809-890 Nier AO (1940) A mass spectrometer for routine isotope abundances measurement. Rev Sci Instrum 11 212-216... 

Nier, A.O. The Development of a High Resolution Mass Spectrometer a Reminiscence. J. Am. Soc. Mass Spectrom. 1991,2,447-452. 

Between the early 1950s, when the dual viscous-flow mass spectrometer was introduced by Nier and the mid 1980s only minor modifications have been made on the hardware of commercial mass spectrometers. Special efforts have been undertaken in the past years to reduce the sample size for isotope measurements. This has led to a modification of the classic dual inlet technique to the continuous-flow isotope ratio monitoring mass spectrometer in which the gas to be analyzed is a trace gas in a stream of carrier gas, which achieves viscous-flow conditions. Today, the majority of gas mass spectrometers are sold with the continuous flow system, instead of the dual inlet system. 

The foundations of stable isotope geochemistry were laid in 1947 by Urey s classic paper on the thermodynamic properties of isotopic substances and by Nier s development of the ratio mass spectrometer. Before discussing details of the naturally occurring variations in stable isotope ratios, it is useful to describe some generalities that are pertinent to the field of non-radiogenic isotope geochemistry as a whole. 

The most recent metastable defocusing technique, which is referred to as mass-analyzed ion kinetic spectroscopy (MIKES) by Beynon (77, 270, 277) and as direct analysis of daughter ions (DADI) by Maurer (278) requires the interchange of the source and collector positions in a double-focusing mass spectrometer of Nier-Johnson geometry. With... 

Figure 1.14 Schematic of a 60° magnetic sector field mass spectrometer (Nier s mass spectrometer, 1940) 5, - entrance slit S2 - exit slit (H.Kienitz (ed.), Massenspektrometrie (1968), Verlag Chemie, Weinheim. Reproduced by permission of Wiley-VCH.)...

Nier s instrumentation, in comparison to the mass spectrometers existing at that time in 1934, was well developed and was extensively used for a quite different application during the Manhattan Project (1940-1945) for separation of uranium isotopes. It is well known that the 235U isotope... 

A mass spectrometer with Mattauch-Herzog geometry was also selected by Nier for space research due to its ability to meet the strict requirements imposed by rockets and satellites without seriously compromising performance and versatility.14... 

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