No abstract available

[en] Equilibrium experiments have shown Pu⁺⁴ to be absorbed from nitric acid onto an anion resin as a complex anion Pu(NO₃)₆^-2. The amount of absorption is dependent on the plutonium and nitric acid concentrations in the equilibrium solution with a maximum at 7N to 8N HNO₃. A low cross-linked resin has a higher capacity and reaches equilibrium more rapidly than the normally supplied resin. Saturation capacity of one per cent cross-linked Nalcite SBR (Dowex 1), 50 -- 100 mesh, is 385 mg Pu/gram dry resin. (author)

No abstract available

[en] The total number of delayed neutrons per fission, v-bar_d and the time dependence of the delayed neutron emission rate are important parameters for reactor design and safety studies, as they determine the behavior of reactors to rapid changes in operation. The parameters for fissioning systems important for current reactor technology have been determined experimentally, for others, important for potential future technologies, where accurate measurements are difficult to make they can be determined from estimates of fission product yields and decay data, by the summation method. This submission describes delayed neutron validation work carried out on JEF-2.2 in the 1990’s with some small recent additions that attempts to gauge the accuracy of this method for delayed neutron time dependence against experiment

[en] An experimental search has been made for isotopic mass effects in a system where small light molecules diffuse in a solvent of larger and heavier molecules. No effect was observed within the experimental precision of a few tenths of a percent. This result does not agree with the hard-sphere molecular dynamics study of Alder, Alley, and Dymond

[en] The concept of gauge invariance has been generalized to apply isotopic spin conservation. It turns out that a very natural generalization is possible. The field that plays the role of the electromagnetic field is here a vector field that satisfies a nonlinear equation even in the absence of other fields. (This is because unlike the electromagnetic field this field has an isotopic spin and consequently acts as a source of itself.) The existence of a current density is automatic, and the interaction of this field with any fields of arbitrary isotopic spin is of definite form (except for possible terms similar to the anomalous magnetic moment interaction terms in electrodynamics)

[en] Reference is made to Miller (Nature 243 : 32 (1973)) who found that UO₂²⁺ ions diffusing in aqueous solution showed an isotope effect, and also that heavier ions diffuse faster than lighter ions. Miller attributed this to kinetic effects in the molecular diffusion process. The effects should apply generally to heavy ions diffusing in light solvents, and it was thought that the difference in diffusion coefficients should be measurable. Experimental work is here reported designed to test this supposition. The heavy ions chosen for study were the pairs ¹²⁵I^- -¹³¹I^- and ¹³⁴Cs⁺ - ¹³⁷Cs⁺, and diffusion coefficients for these ions were measured using the magnetically stirred diaphragm cell method. Conditions varied were temperature, concentration, and type of diffusion. Results are shown tabulated, and showed no detectable isotope effect under a variety of conditions. (U.K.)

[en] It is shown that if the Lagrangian density for a gauge field is taken as an appropriate nonlinear function of the usual Lagrangian density, there results a simple classical model of confinement that has nothing to do with the non-Abelian character of the gauge group. Plane-wave solutions are suppressed, suggesting confinement of the gauge quanta as well

[en] In recent years there has been a trend in Swedish Probabilistic Safety Analysis (PSA) work towards coordination of the tools and methods used, in order to facilitate exchange of information and review. Thus, standardized methods for fault tree drawing and basic event coding have been developed as well as a number of computer codes for fault tree handling. The computer code used by Asea-Atom is called SUPER-TREE. As indicated by the name, the key feature is the concept of one super tree containing all the information necessary in the fault tree analysis, i.e. system fault trees, sequence fault trees and component data base. The code has proved to allow great flexibility in the choice of level of detail in the analysis

[en] Extraction of coal ceased in the Weavers Open Cast Mine, Huntly, New Zealand in December 1993. A condition of the environmental Resource Consent for mine development was that following completion of mining, the pit void and adjacent overburden dumps were to be rehabilitated as a high quality lake environment suitable for wildlife and recreation. This paper describes the geotechnical aspect of the rehabilitation work. It focuses on development of the risk management strategy to manage pitwall instability during lake filling. The adopted strategy is expected to produce significantly lower capital costs for the rehabilitation work compared to an alternative strategy requiring expensive slope stabilisation works on sectors with low stability levels. 2 refs., 5 figs., 2 tabs