Tritium, representation

Fig. 9 Schematic representation of the scintillation proximity assay of (S)-propanolol using imprinted microspheres. The light green area represents the aromatic antenna element, (a) The bound, tritium-labeled (S)-propranolol triggers the scintillator to generate a fluorescent light, (b) When the tritium-labeled (S)-propranolol is displaced by the unlabeled (S)-propranolol, it is too far away from the scintillator antenna to transfer efficiently the radiation energy therefore, no fluorescence can be generated (as described in [62])...

When tritium-labeled sparteine is administered to the plant it gives rise to radioactive lupanine and hydroxysparteine. Lupinine- C is changed to sparteine in recognizable amounts. The equation below is a representation of the above facts. 

Fig. 4.1 Schematic representation of hydrogen isotopes protium (H), deuterium (D) and tritium (T).

Scheme 13.22. A representation of experiments showing the results of deuterium- and tritium-labeled phenyllactate feedings to Datura stramonium. The results shown must be accounted for in any subsequently formulated mechanism (yet forthcoming). After Chesters, N. C. J. E. Walker, K. O Hagen, D. Floss, H. G. /. Am. Chem. Soc., 1996,118,925 and Chesters, N. C. J. E. O Hagen, D. Robins, R. J. Kastelle, A. Floss, H. G. J. Chem. Soc. Chem. Commun., 1995,129.

The first isotcpe, with 235 — 92 = 143 neutrons in its nucleus, is used in nuclear reactors and atomic bombs, whereas the second isotr, with 146 neutrons, lacks the fffoperties necessary for these applications. With the exception of hydrogen, which has different names for each of its isotopes, the isotopes of other elements are identified by their mass numbers. The two isotopes of uratrium are called uranium-235 (pronounced Tiianium two thirty-five ) and uranium-238 (jx onounced uranium two thirty-eight ). Because the subscripted atomic number can be determined from the elemental symbol, it may be omitted from these representations without the loss of any inframatirai. The symbols and are sufficient to spediy the isotopes tritium and uranium-235, respectively. 

One should realize that the catalyst approaches the prochiral double bond from the a-si, p-re face. (For an introduction to the nomenclature used to differentiate the two carbons of a prochiral double bond see Section 4.2.1.) Deuterium ( H) and tritium ( H) atoms are heavy isotopes of hydrogen ( H) but for the clarity of the structural representations only, the symbols D and T are used throughout this text. 

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