Nitrogen isotope separation

Some nitrogen isotope separation is also observed (6). 

Fractional distillation of NO is an effective method for concentrating N. Chemical exchange processes for nitrogen isotope separation include the following ... 

Alkali etching of glass was also employed by Bruner eind co-workers as well as by o er researchers [86-89]. They etched the column walls with 20% NaOH solution for 6 h with subsequent activation in a nitrogen stream at 200 °C. The finished column was useful in oxygen and nitrogen isotope separation. 

Laser isotope separation techniques have been demonstrated for many elements, including hydrogen, boron, carbon, nitrogen, oxygen, sHicon, sulfur, chlorine, titanium, selenium, bromine, molybdenum, barium, osmium, mercury, and some of the rare-earth elements. The most significant separation involves uranium, separating uranium-235 [15117-96-1], from uranium-238 [7440-61-1], (see Uranium and uranium compounds). The... 

Kirkley MB, Gurney JJ, Otter ML, HiU SJ, Daniels LR (1991) The application of C-isotope measurements to the identification of the sources of C in diamonds. Appl Geochem 6 477 94 Kirshenbaum I, Smith JS, Crowell T, Graff J, McKee R (1947) Separation of the nitrogen isotopes by the exchange reaction between ammonia and solutions of ammonium nitrate. J Chem Phys 15 44(M46... 

As of early September, 1985, the facility is being commissioned. Carbon, nitrogen and oxygen beams from the tandem have reached the interim target locations via the bypass line, and an iodine beam has been injected into the cyclotron. First attempts to accelerate iodine in the cyclotron are imminent Some experimental equipment, including the on-line isotope separator [SCH81J, is already set up and undergoing tests with tandem beams. 

Figure 6. Schematic diagram of a two section cascade for preparation of highly enriched nitrogen-15. Proceedings of the International Symposium on Isotope Separation (Ref. 17) North Holland Publishing Co.

Finally we emphasize that a number of interesting separations have been reported at isolated temperatures and for this reason have not been mentioned in the brief summary comprising this section. Examples include separations of 2 from 2 , (8), deuterated from non-deuterated trimethylsilyl derivatives of sugars (5), some assorted hydrocarbon separations on safrole (28), and a partial separation of the nitrogen isotopes (30). 

Fig. 6.13 Plot of carbon and nitrogen isotopes in pottery from Mesolithic (Tybrind Vig and Ringkloster) and Neolithic sites (Funnel Beaker). A distinct separation of these two groups is seen reflecting the more terrestrial diet of the Neolithic farmers. This pattern is also seen in the carbon and nitrogen isotope ratios in human bone collagen from the Mesolithic and Neolithic in this region...

Table 12.6 Methods used for separating nitrogen isotopes...

T2. Taylor, T. I., and W. Spindel Preparation of Hi y Enriched Nitrogen-15 by Chemical Exchange of NO with HNO3 > Proceedings of the International Sympomm on Isotope Separation, Interscience, New Yoric, 1958, p. 158. 

Saraceno, A. J., and C. F. Trivisonno (eds.) Uranium Isotope Separation by Chemical Exchange Reactions Between UF and UFj-Nitrogen Oxide, Report GAT-674, Feb. 4, 1972. 

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