[en] The purpose of this paper is to discuss the role of biosphere modelling in relation to the overall assessment of disposal of solid radioactive waste. Model structure and data requirements are strongly influenced by a number of basic factors. Firstly, the alternative forms of safety criteria and regulatory requirements imply different end-points for biosphere models. Secondly, alternative disposal concepts can influence the significance of the biosphere as a barrier or diluting/concentrating feature affecting exposure of man. Thirdly, the range of different possibilities for release to the biosphere, including releases following intrusion, is very extensive. The requirements and state of development of biosphere models are discussed in relation to these factors along with methods being adopted to provide some expression of confidence in model results. 37 refs

[en] A range of structural materials are considered including conventional steels and low activation steels and alloys. waste management options considered are shallow land burial, deep geological disposal, deep ocean disposal, and recycling with useful product returned to the fusion reactor and disposal of secondary wastes. The implications of a range of intermediate cooling times are also examined. The main conclusions are that none of the waste materials considered is likely to be suitable for shallow land burial; for the other options there are no major post-disposal safety advantages in using the lower activation materials considered, although there will be operational advantages; recycle of wastes could have some post-disposal radiological advantages, but the impact on workers and the economic and strategic advantages need also to be taken into account; more information is required about the arisings of some radionuclides and their behaviour in recycling plant, the geosphere and biosphere, notably ¹⁴C and sup(186m)Re, in order to guide the further development of suitable candidate structural materials. (author)

[en] This report describes a compartment model, BIOS, for predicting rates and patterns of dispersal of radionuclides in the biosphere following release of activity from the geosphere, and for calculating individual and collective doses. The model is intended primarily for use in the calculation of the radiological impact following geologic disposal of radioactive wastes, but it can also be used for other purposes. To apply the model in site-specific assessments, the user needs to provide data on the local environment. Important features of the model are its comprehensiveness (all parts of the environment, all major pathways and individual and collective doses are considered), its flexibility, and its ability to take account of changes in biosphere conditions with time. (author)

[en] The purpose of the work described is to provide estimates of the radiological impact following disposal of unit activity via each of several options, including shallow burial, engineered trench disposal, disposal in a geologic repository and disposal on the deep ocean bed. Results are presented for a range of important representative radionuclides. No single option is clearly the best from the radiological point of view. However, in conjunction with waste inventory data the results may be used to provide a preliminary view of the relative radiological merits of the various disposal options. (author)

[en] The novel unesterified alkyl glycerol monoethers, (2S)-1-(hexadecyloxy)-2,3-propanediol (1), (2S)-1-(16-methylheptadecyloxy)-2,3-propanediol (2) and (2S)-1-(15-methylheptadecyloxy)-2,3-propanediol (3) were isolated from the marine sponge Tethya aurantia and were characterized by spectroscopic methods. These three saturated ethers as well as a series of alk-1'-enyl glycerol monoethers were also encountered in the phospholipids of the same sponge after reduction with LiAlH4. Incorporation experiments with dissociated cells of T. aurantia indicated that [1-¹⁴C]-hexadecanol was incorporated into the unesterified alkyl glycerol monoethers

[en] This paper describes the approach being adopted to improve confidence in biosphere modelling for the assessment of the post-disposal radiological impact of disposal of low and intermediate solid radioactive waste at alternative sites proposed by UK Nirex Ltd. (author)

[en] Short note

[en] The ¹⁵N-enriched ferrocytochrome c₂from Rhodospirillum rubrum was studied by ¹⁵N NMR at different solvent pH values. The mobility and chemical shift to the N-terminal glutamic acid (335.4 ppm at pH 5.1) were found to depend on pH. It was least mobile between pH 8 and 9.0, which is explained in terms of pH-dependent conformational changes and formation of salt linkages and/or hydrogen bonds. The resonances of the lysine side chains are centered around 341.7 ppm at low pH and move upfield with pH by about 8.4 ppm with pH/sub a/ values of 10.8. The exchange rates of the εNH protons are lowest near the pK/sub a/ values. The protein is very stable in the pH range between 4.9 and 10.0 but unfolds abruptly at pH 10.5-11. Denaturation was verified by the measurement of several parameters by NMR. The renaturation of the protein demonstrates that the folding begins with reformation of home coordination and establishment of a hydrophobic core, followed by positioning of side chains and peptide backbones linking the nucleation centers. The repositioning processes had time scales of minutes to hours in contrast to the reported values of seconds in some studies

No abstract available

[en] The main purpose of the Annex is to describe the methodologies and models used in this study to calculate the radiological impact of /sup 129/I management. Sect. 10 of the Joint Report covers the same topics, but more briefly and for the non-specialist reader. A small amount of material has been reproduced from the Joint Report without further elaboration, in order to achieve continuity of presentation in the Annex, though most topics are treated here in more detail. The Joint Report contains a full discussion of the results obtained, so in the Annex the results are presented without comment. Finally, some recent related studies are briefly reviewed in order to set the present work into context