Microscopic Determinations of Fission Barriers, (MEAN-Field and Beyond)

With a help of the selfconsistent Hartree-Fock-Bogoliubov (HFB) approach with the D1S effective Gogny interaction and the Generator Coordinate Method (GCM) we incorporate the transverse collective vibrations to the one-dimensional model of the fission-barrier penetrability based on the traditional WKB method. The average fission barrier corresponding to the least-energy path in the two-dimensional potential energy landscape as function of quadrupole and octupole degrees of freedom is modified by the influence of the transverse collective vibrations along the nuclear path to fission. The set of transverse vibrational states built in the fission valley corresponding to a successively increasing nuclear elongation produces the new energy barrier which is compared with the least-energy barrier. These collective states are given as the eigensolutions of the GCM purely vibrational Hamiltonian. In addition, the influence of the collective inertia on the fission properties is displayed, and it turns out to be the decisive condition for the possible transitions between different fission valleys.Comment: 12 pages, 5 figures, presented at XIII Workshop of Nuclear Physics, Kazimierz Dolny, 2006 (Poland

Cautyʼs space enhanced

AbstractThe title refers to Cautyʼs example (Cauty, 1994 [3]) of a metric vector space which is not an absolute retract. It is shown that Cautyʼs space can be refined to the effect that the completion of the refined space can be isomorphically embedded as a subspace of an F-space which itself is an absolute retract

Valuation theory, generalized IFS attractors and fractals

Using valuation rings and valued fields as examples, we discuss in which ways the notions of “topological IFS attractor” and “fractal space” can be generalized to cover more general settings

Pea and faba bean symbiosis with Rhizobium.

Trial 89WH55, 89KA57, 89M26, 90A12, 90A13, 90M59, 90M60 Location: Merredin, Konnongorring, Dalwallinu, Wongan Hills, Kojonup, Avondale Research Station. To undertake relevant field studies to establish whether there are constraints to pea and bean symbiosis, arising from management, environment or genetics, and affecting crop N accumulation and productivity. Trial 90BA60 Using Le-mat (omethoate) insecticide and legume inoculant on seed. Location: Badgingarra Research Station, To measure the effect of Lemat on the nodulation and growth of medics and luceme

Alternative Routes from Fossil Resources to Chemical Feedstocks

The chemical industry depends very heavily on hydrocarbon feedstocks, which are presently derived almost exclusively from crude oil. Although only about seven percent of the hydrocarbons suitable for chemical processing are actually used in this way, it is already clear that there is a potential conflict between the needs of the energy sector and those of the chemical industry: they are competing for increasingly scarce liquid hydrocarbon resources. The authors suggest that the supply of hydrocarbon feedstocks to the chemical industry could be protected against the effects of changing patterns of energy use by modifying the underlying industrial structure. They have developed an approach which takes a variety of production processes (either in use or under development), compares their efficiency their consumption of different resources, etc., and finds the combination of technologies that best satisfies a particular demand while staying within the limits imposed by resource availability. This approach uses the techniques of interactive decision analysis to incorporate the unquantifiable social and political factors that must influence any development decision. By way of illustration, the method is applied to one very small part of the problem area: the different routes to the production of methanol. This report does not attempt to provide any final answer to the problem of feedstock supply, but rather to explain one possible approach to the problem and discuss some intermediate results. It is addressed not only to researchers, but also, and in particular, to all decision makers and industrial consultants facing problems of this type

Magnetoresistance of a semiconducting magnetic wire with domain wall

We investigate theoretically the influence of the spin-orbit interaction of Rashba type on the magnetoresistance of a semiconducting ferromagnetic nanostructure with a laterally constrained domain wall. The domain wall is assumed sharp (on the scale of the Fermi wave length of the charge carriers). It is shown that the magnetoresistance in such a case can be considerably large, which is in a qualitative agreement with recent experimental observations. It is also shown that spin-orbit interaction may result in an increase of the magnetoresistance. The role of localization corrections is also briefly discussed.Comment: 5 pages, 2 figure

First generation of optical fiber phase reference distribution system for TESLA

This report describes the design of a phase stable Fiber Optic (FO) link for the TESLA technology based projects. The concept of this long optical link, with a feedback system suppressing long term drifts of the RF signal phase is described. Stability requirements are given and most important design issues affecting the system performance are discussed. The technical design issues of system components like laser transmitter and optical phase shifter are described in detail. Last sections depict the software developed for system control and experimental results obtained after system was assembled