Nuclear method

The neutron activation technique mentioned in the preceding paragraph is only one of a range of nuclear methods used in the study of solids - methods which depend on the response of atomic nuclei to radiation or to the emission of radiation by the nuclei. Radioactive isotopes ( tracers ) of course have been used in research ever since von Hevesy s pioneering measurements of diffusion (Section 4.2.2). These techniques have become a field of study in their own right and a number of physics laboratories, as for instance the Second Physical Institute at the University of Gottingen, focus on the development of such techniques. This family of techniques, as applied to the study of condensed matter, is well surveyed in a specialised text 

Nuclear magnetic resonance is another characterisation technique of great practical importance, and yet another that became associated with a Nobel Prize for Physics, in 1952, jointly awarded to the American pioneers, Edward Purcell and Felix Bloch (see Purcell et at. 1946, Bloch 1946). In crude outline, when a sample is placed in a strong, homogeneous and constant magnetic field and a small radiofrequency magnetic field is superimposed, under appropriate circumstances the 

Another relatively recent technique, in its own way as strange as Mossbauer spectrometry, is positron annihilation spectrometry. Positrons are positive electrons (antimatter), spectacularly predicted by the theoretical physicist Dirac in the 1920s and discovered in cloud chambers some years later. Some currently available radioisotopes emit positrons, so these particles arc now routine tools. High-energy positrons are injected into a crystal and very quickly become thermalised by 

Laboratory, particularly to study ferrimagnetic materials. In 1994, a Nobel Prize in physics was (belatedly) awarded for this work, which is mentioned again in the next chapter, in Section 7.3. A range of achievements in neutron crystallography are reviewed by Willis (1998). 

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Nuclear methods which include a variety of radioactive elements as in organic reagents, complexes or salts. 

Schatz, G. and Weidinger, A. (1996) Nuclear Condensed Matter Physics Nuclear Methods and Applications (Wiley, Chichester). 

Roark D, Yphantis DA (1969) Ann New York Acad Sci 164 245 Rinde H (1928) The Distribuhon of the Sizes of Particles in Gold Sols Prepared According to the Nuclear Method. PhD Thesis, University of Uppsala, Uppsala, Sweden Harding SE (1988) Gums and Stabilisers for the Food Industry 4 15 http //www.wyatt.com/... 

Analytical Chemistry Division, Nuclear Methods Group, Bid. 235, Rm. B-125 Gaithersburg, MD 20899, USA E-mail rolf.zeisIer nist.gov... 

The characteristics of radiochemical methods are well known [435]. An overview of the determination of elements by nuclear analytical methods has appeared [436]. Some selected reviews of nuclear methods of analysis are available charged particle activation analysis [437,438], instrumental neutron activation analysis [439-441] and ion-beam analysis [442]. 

INAA was recently reviewed [452,453]. Various books deal with radioanalytical chemistry and nuclear methods of analysis [435,454-458]. A nuclear spectrometry handbook is available [459]. 

W.D. Ehmann and D.E. Vance (eds), Radiochemistry and Nuclear Methods of Analysis, Wiley-Interscience, New York, NY (1991). 

Roth, E. and B. Poty (1989), Nuclear Methods of Dating, Kluwer, Boston. 

It is necessary to pay attention to environmental radioactivity when peaceful applications of nuclear methods are developed for various fields of science and technology. The importance of technetium in environmental safety was socially recognized not so long ago. The Commission of the European Communities... 

Heft, R. E., Harrison, F. L. and Phillips, W. A. (1971). Radioecological study of the Humboldt Bay marine environment, page 158 in Nuclear Methods in Environmental Research, USAEC Report No. CONF-710818, Vogt, J. R., Parkinson, T. F. and Carter, R. L., Eds. (University of Missouri, Columbia, Missouri). 

Howe, L., Swanson, M., and Davies, J. (1983). Methods of Experimental Physics Solid State Nuclear Methods 21, 275. 

Glascock, M.D. (1994). Nuclear reaction chemical analysis prompt and delayed measurements. In Chemical Analysis by Nuclear Methods, ed. Alfassi, Z.B., John Wiley, Chichester, pp. 75-99. 

M. Baldo (Ed.), Nuclear Methods and the Nuclear Equation of State (World Scientific, Singapore, 1999). 

Ehmann, W.D. and Vance, D.E. (eds) (1991) Radiochemistry and nuclear methods and analysis, Blackwell Scientific Publications, UK. 

Shortly after the development of the early mass spectrometers, Li isotopes were identified by Francis Aston (1932). Although mass spectrometric techniques are those most commonly applied to the measurement of isotope ratios in geochemistry, attempts to quantify Li isotopes have been made using non-mass based emission methods (e.g., atomic absorption Zaidel and Korennoi 1961 various nuclear methods Kaplan and Wilzbach 1954 Brown et al. 1978 ... 

L.H. (1990) Magnetic properties of some selected, sod-related iron oxides and oxyhydroxides as probed by Fe Mossbauer spectroscopy. In Stanek, J. Pedziwiatr, A.T. (eds.) Condensed matter studies by nuclear methods. Proc. XXIV Zakopane School on Physics. 

Rhelngrover, S. W. Gordon, G. E. " Identifying Locations of Dominant Point Sources of Elements In Urban Atmsopheres from Large, Multi-Element Data Sets", In Proc. of the 4th Int. Conf. on Nuclear Methods In Environmental and Energy Research, Unlv. of Missouri, Columbia, MO, Apr., 1980, J. R. Vogt, ed. (In press). 

Heft, R.E., paper presented at the Third International Conference on Nuclear Methods in Environmental Energy Research, Columbia, Mo., Oct 10-13, 1977. 

Table 16-2. The time-, energy-, and diffusivity ranges for various nuclear methods [W. Petry, O. Yogi (1987))...

Finally, the perturbed y-y angular correlation (PAC) nuclear method has been shown to register adequately with in-situ solid state chemical reactions, both on microscopic and macroscopic scales. The analysis of PAC is, in principle, more complicated than that of MS because two consecutive y-emissions and their correlation are involved in the spectroscopic process. 

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