Application to environmental problems

M. Gascoyne, in Uranium Series Disequilibrium Applications to Environmental Problems, ed. M. Ivanovich and R. S. Hannon, Clarendon Press, Oxford, 1982, pp. 32-55. 

M. Scott, in Uranium Series Disequilihria Applications to Environmental Problems, ed. M. 

Scott MR (1982) The chemistry of U- and Th-series nuchdes in rivers. In Uranium series disequilibrium Application to environmental problems. Ivanovich M, Harmon RS (eds) Oxford Sciences Publications, Oxford, p 181-201... 

Within Severn Trent a modified version of this procedure is utilised for the analysis of malodorous emissions. The most significant difference in this approach compared to those already discussed is the use of high resolution gas chromatography in combination with olfactory detection. This method also combines physico-chemical and olfactometric or sensory techniques but in an alternative manner. Utilisation of gas chromatography combined with odour detection is not a new concept and has been employed fairly commonly for the analysis of food aromas, essential oils and other fragrances. The technique is equally applicable to environmental problems and is used frequently in this laboratory for the analysis of atmospheric emissions and taste and odours in water. Three important benefits accrue from this approach in the context of odour emission analysis. 

Jendrzejewski N, Eggenkamp HGM, Coleman ML (2001) Characterization of chlorinated hydrocarbons from chlorine and carbon isotopic compositions Scope of application to environmental problems. Appl Geochem 16(9-10) 1021-1031... 

System Characterization. A further limitation to the adequate testing of chemical models and to their application to environmental problems is the extensive system characterization (especially chemical analyses) often required. Adequate characterization often necessitates many difficult and time-consuming analyses, some of which must be done on site, and the collection— with adequate preservation—of numerous subsamples. 

Scott, M.R., The chemistry of U- and Th-series nuclides in rivers, pp. 181-201. In M. Ivanovich and R.S. Harmon (ed.) Uranium series disequilibrium applications to environmental problems. Oxford Univ. Press, Oxford, 1982. 

One difficulty in conducting a large number of applications is organizing the applications and their data. A standardized approach is needed to allow a consistent definition of environmental problems. For example, a formal classification of environmental problems can provide a framework for data organization. Although the approach was largely dictated by the Environmental Survey s classification, the MEPAS structure should be applicable to environmental problems in general. 

Thus, historical problems with NRS, primarily high detection levels and interference with fluorescence, severely hampered applications to environmental problems in the past. However with the development over the last decade of CCD-based systems and FT-Raman systems, the severities of these problems have been greatly reduced. For example, NRS is now capable of 10 M detection levels with CCD-based systems in some cases [26]. Also, it is now possible to observe the NRS spectrum of humic acid (extremely fluorescent when excited with visible excitation) with an FT-Raman system using 1064-nm excitation. The great promise of NRS for environmental analysis (including trace analysis) of aqueous systems has truly arrived. 

Since 1970, researchers have recognized that RS offers great promise for environmental analysis because measurements can be made directly on contaminants in water [9]. Unfortunately, developments in this area were slow until recently because of the historical problems associated with RS, namely high detection levels, severe problems with fluorescence backgrounds, and the need for large and complex instrumentation. However, as we have described, the sensitivity of NRS has increased considerably over the decade prior to this writing. This improvement is due to advances in instrumental components that make up the modem dispersive Raman instmment. Also, advances in instmmental components have made these spectrometers more compact and portable, able to record spectra much quicker, less hindered by fluorescence, much simpler and less dependent on specialized facilities, more amenable to remote application, and much easier to operate. All of these improvements have led recently to more widespread application to environmental problems in aqueous systems, as illustrated in Table 1. However, further improvement will be needed for the full potential of RS to be realized in this arena. 

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