Nonuniform radio-frequency plasma potential due to edge asymmetry in large-area radio-frequency reactors

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Aerobic granular sludge technology offer a possibility to design compact wastewater treatment plant based on simultaneous COD, nitrogen and phosphate removal in a sequencing batch reactor.Simultaneous nutriment removal was possible, because of heterotrophic growth inside the granules (denitrifying and PAO organisms). Selection for slow growing organisms such as PAO organisms (byincrease of the feeding period time) also allow to improve granule stability and density. This study was aimed to investigate the g

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We have investigated the effect of different ion cyclotron resonance frequency (ICRF) heating schemes, of error field modes, of the plasma shape and edge magnetic shear, and of the ion delB drift direction on the stability of Alfven eigenmodes (AEs). The use of multi-frequency or 2nd harmonic minority ICRF heating at high plasma density gives rise to a lower fast ion pressure gradient in the plasma core and to a reduced mode activity in the Alfven frequency range. Externally excited low-amplitude error fiel

We introduce a variational total-energy functional to treat finite homogeneous electric fields with periodic boundary conditions and show that this functional can be implemented within a Car-Parrinello molecular dynamics scheme. The Coupling to an electric field is achieved through the Berry-phase expression of the polarization. The minimization of this extended functional gives a ground state which describes the polarized state in ail electric field. For a crystalline system, the ground state of this exten

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An effective way to reduce the large quantities of Pu currently accumulated worldwide would be to use uranium-free fuel in light water reactors (LWRs) so that no new Pu is produced. Such a possibility could be provided by an LWR fuel consisting of Pu in a neutronically inert matrix. It may be necessary to add a burnable absorber or thorium to reduce the reactivity swing during burnup. The methods and data currently used for LWR analyses have not been tested in conjunction with such exotic fuel materials. An

In the scope of the study of low-frequency electrostatic microinstabilities in tokamak plasmas, attention has been focused on the effect of trapped ions. The ballooning transform has been applied to the gyrokinetic equation, for the case of a large aspect ratio plasma with circular magnetic surfaces. A new eigenvalue code has been developed to solve the resulting integral equation, for the case of adiabatic electrons and full ion dynamics, thus taking into account both circulating and trapped ions. The goal

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A solution to the full two-dimensional eigenvalue problem of electrostatic microinstabilities in a tokamak plasma is presented in the framework of gyrokinetic theory. The approach is the generalization of methods previously developed for a cylindrical system [S. Brunner and J. Vaclavik, Phys. Plasmas 5, 365 (1998)]. By solving the spectral problem in a special Fourier space adapted to the curved geometry, orbit width as well as Larmor radius can be kept to all orders. For a first numerical implementation, a

In this paper we present one-dimensional numerical simulations of compression and burn of a high-gain indirect drive inertial fusion target suitable for use in a reactor system. The target consists of a capsule that contains 4.45 mg of DT fuel and the capsule is enclosed in a solid gold casing. The inner radius of the casing is twice larger than the outer radius of the capsule so that the inner surface area of the hohlraum wall is four times larger than the capsule surface area. The cavity is filled with a

Nonuniform radio-frequency plasma potential due to edge asymmetry in large-area radio-frequency reactors

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Aerobic granular sludge reactor technology Aerobic granulation in bubble column reactor at unregulated temperature

Planar and Tubular perovskite-type membrane reactors for the partial oxidation of methane to syngas

Alfven mode stability and wave-particle interaction in the JET tokamak: prospects for scenario development and control schemes in burning plasma experiments

Car-Parrinello Molecular Dynamics in a Finite Homogeneous Electric Field

Geometry considerations for transport current applications of Bi-2223 conductors with anisotropic Jc(B) in external magnetic field

Comparisons of cell calculations for uranium-free light water reactor fuels

Applicability of the ballooning transform to trapped ion modes

Frequency dependence of A.c. loss in Bi(2223)Ag sheathed tapes

Stability analysis of the vertical position control loop in TCV using rigid and deformable plasma models

Topologic study of a magnetic perturbation in a 3D free boundary plasma equilibrium

Global approach to the spectral problem of microinstabilities in tokamak plasmas using a gyrokinetic model

Simulations of Compression and Thermonuclear Burn of an Indirect Drive Reactor-Size Inertial Fusion Target