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Nuclear Fission Energy
Published in Heinz Knoepfel, Energy 2000, 2017
The enrichment of uranium with its fissile isotope uranium 235, from its natural concentration of 0.7% to around 3%, is a major operation in the preparation of the nuclear fuel required by light water reactors. Enrichment presupposes the capability of separating the isotope uranium 235 from the more abundant uranium 238. On an industrial scale this is done by diffusion or centrifuge methods of the chemical compound UF6-uranium hexafluoride, commonly known as “hex.” On the laboratory scale, or in pilot plants, separation is also obtained by means of supersonic nozzles, electromagnets, lasers, or by exploiting special effects in chemical reaction dynamics or in plasma rotation. The laser separation method looks promising and has been chosen by the U.S. Department of Energy as the method for the future. Historically, the first method applied in 1944 on a large scale was the electromagnetic mass separation obtained in the huge “Calutron” magnet units at Oak Ridge (Fig. 3.6).
The Hamiltonian Approach to Electrodynamics
Published in V. L. Ginzburg, Oleg Glebov, Applications of Electrodynamics in Theoretical Physics and Astrophysics, 2017
Since the energy of the field of a point charge is infinite, it is often useful to assume, at least for intermediate calculations, that the charge is smeared out over a region of radius r0. Then we have ℋ1~e2/r0. The electrostatic (classical) radius of the electron given by the equation re = e2/mc2, where e and m are the observed charge and mass of the electron, is re = 2.8 × 10−13 cm. We shall ignore here the problems arising from the electromagnetic mass of the electron (and other particles), the singularity of the point charge etc. (see the relevant discussion in Chapter 2).
Role of surface gauging in extended particle interactions: the case for spin
Published in Maricel Agop, Ioan Merches, Operational Procedures Describing Physical Systems, 2018
If it is to assign masses to forces by an extended principle of inertia, then these masses cannot be tensors, as in the classical case of the electromagnetic mass, but coefficients connecting the forces to the spin properties of matter which, again, cannot be revealed but within an extended particle model. The masses are simply three coefficients which, if geometrically conceived, cannot be but coordinates in a threedimensional Lorentz geometry. The whole theory of forces is then a gauge theory based on spin properties of matter, of which we presented in this work a representative, based on the following general philosophy.
Modeling and structural control of a building with holonomic constraints
Published in Australian Journal of Structural Engineering, 2022
Carlos F. Rengifo, Diego A. Bravo
Structural control is an active area of research (Chiaia et al. 2020; Shih and Sung 2020; Reksowardojo and Senatore 2020; Di Girolamo et al. 2020). (Zhang and Ou 2015) propose an electromagnetic mass driver system (EMDS) for the control of structural vibrations. The EMDS consists of a rod made of tiny permanent magnets, which moves horizontally along the axis of an electric coil fixed to the structure to be controlled. The Lorenz force exerted on the coil counteracts earthquake-induced vibrations and varies with the voltage applied to the coil. This means that there is no mechanical contact between the rod and the structure, which leads to an unlimited mass stroke, lower operating noise, and limited wearing of moving parts. In addition, EMDS is faster and simpler than active mass dampers based on hydraulic systems or electric motors.