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The ideal magnetohydrodynamic (MHD) model is extended to include arbitary equilibrium flows and multiple fluids and an equivalent variational form is developed. This system is appropriate for the study of stability in any multi‐fluid flowing plasma, e.g., allowing for arbitrary poloidal and toroidal equilibrium flows and accounting for the Hall effect. This variational form was applied to the stabilization of the rotational instability in field‐reversed configurations (FRCs) by an energetic ion beam. It is found that if the ratio of the rotational frequency of beam ions to that of background plasma ions exceeds a critical value, the radial displacements of plasma and beam ions are opposite, and the rotational instability can be suppressed. It is also found that the beam energies and currents required for stabilization are small fractions of the energy and current of the background plasma.

A two-fluid equilibrium model with low-collisionality is developed including a new flow-singularity condition. This description is applied to the rapidly rotating, high-performance National Spherical Torus eXperiment (NSTX) [Peng et al., Plasma Phys. Controlled Fusion 47, B263 (2005)]. The model replicates the primary features of an example equilibrium, such as the profiles of electron and ion temperatures, density, and toroidal flow of an example equilibrium. This is the first full-two-fluid computation of two-dimensional equilibrium with rapid ion flow near the thermal speed. In consequence several important features emerge: (1) the ion toroidal current exceeds the toroidal plasma current as a result of electron rotational flow reversal; (2) the ion flow in the core region is roughly parallel to the magnetic field, i.e., the ion fluid in the core is nearly force free; (3) E+ui×B differs considerably from zero, so that the E×B drift fails to describe the ion and electron flows perpendicular to the magnet...

QUEST focuses on the steady state operation of the spherical tokamak by controlled PWI and electron Bernstein wave current drive. One of the main purposes of QUEST is an achievement of long duration discharge with MW-class injected power. As the result, QUEST should be operated in the challenging region on heat and particle handling. To do the particle handling, high temperature all metal wall up to 623 K and closed divertors are planned, which is to realize the steady-state operation under recycling ratio, R = 1. This is a dispensable check to DEMO, because wall pumping should be avoided as possible in the view of tritium retention. The QUEST project will be developed in increment step such as, I. low β steady state operation in limiter configuration, II. low β steady state operation in divertor configuration, III. relatively high β steady state operation in closed divertor configuration. Phase I in the project corresponds to these two years, and final goal of phase I is to make full current drive plasma up to 20 kA. Closed divertor will be designed and tested in the Phase II. QUEST is running from Oct., 2008 and the first results are introduced.

The nearby-fluids model is an improvement of the basic two-fluid flowing equilibrium system developed elsewhere [L.C. Steinhauer, Phys. Plasmas 6, 2734 (1999)]. The two-fluid system is a singular perturbation problem in which the usually small ion-inertia length (ion skin depth) gives rise to a small parameter. This has frustrated attempts to find practical equilibria. The nearby-fluids ordering assumes that the ion and electron flow surfaces are close to (“nearby”) each other but do not coincide exactly. This eliminates the singularity and “softens” the stiff differential equations, thus facilitating numerical solution. Previous treatments of two-fluid equilibria did not find a smooth transition to the single-fluid magnetodynamics (MHD) model in the small ion-inertia-length limit. This difficulty is only partly eliminated by recognizing that the electric field is ordered “large” in MHD. A small but nonzero ion-inertia length produces several important effects, including the appearance of a transition lay...

The Translation-Confinement-Sustainment facility has been operated in the 'translation-formation' mode in which a plasma is ejected at high-speed from a {theta}-pinch-like source into a confinement chamber where it settles into a field-reversed-configuration state. Measurements of the poloidal and toroidal field have been the basis of modeling to infer the safety factor. It is found that the edge safety factor exceeds two, and that there is strong forward magnetic shear. The high-q arises because the large elongation compensates for the modest ratio of toroidal-to-poloidal field in the plasma. This is the first known instance of a very high-{beta} plasma with a safety factor greater than unity. Two-fluid modeling of the measurements also indicate several other significant features: a broad 'transition layer' at the plasma boundary with probable line-tying effects, complex high-speed flows, and the appearance of a two-fluid minimum-energy state in the plasma core. All these features may contribute to both the stability and good confinement of the plasma.

The three magnetohydrodynamic (MHD) waves are followed as they transition under the influence of an increasingly strong Hall current effect to the characteristic waves of the Hall-MHD model. Also followed are the wave normal surfaces and the ray surfaces (approximating wave fronts) of these waves. The changes in the nature of the waves are found to be considerable, and are described both analytically and numerically. Most notably, the incompressible MHD shear Alfven wave becomes a compressible fluid-dynamical wave with negligible perturbation of the electromagnetic field, while the two MHD compressible waves become incompressible, the fast wave becoming mostly electromagnetic and the slow wave becoming mostly fluid-dynamical.

Based on a two-fluid plasma model where the electron mass and the displacement current are neglected, the eigenmode properties such as the frequency and the compressibility are studied. It is found that these properties strongly depend on the two-fluid parameter kli, where k is the wave number of a mode and li is the ion skin depth. Especially it is found that as the two-fluid parameter kli increases beyond unity, the Alfven wave, which is an incompressible mode in the magnetohydrodynamics (MHD) limit, becomes compressible and its phase velocity approaches to the acoustic speed. The slow magnetosonic wave, which is compressible in the MHD limit, becomes incompressible as kli increases. Implications of these results are also discussed.

A discrepancy persists between field-reversed configuration experiments, which are generally stable, and theoretical predictions of instability. The common consensus has been that the stability is the result of finite Larmor radius (FLR) effects. An FLR analysis is presented that finds the self-consistent displacement functions and complex frequency. This is done using the linear gyroviscous model, a fluid-based representation of FLR that allows a wide range of equilibria and modes to be examined with modest computations. The conclusion is that FLR in static FRC fails to explain the observed stability. The cause of stability must lie elsewhere.

The development of catalase (EC 1. 11. 1. 6) activity in Saccharomyces cerevisiae was repressed by the presence of glucose during aerobic culture. The catalase activity of glucose-grown cells increased about 4 times when the cells were aerobically incubated with yeast extract for 3hr. Two catalases, A and T, were detected in the glucose-grown cells by polyacrylamide gel electrophoresis, and the content of catalase A increased with increase of catalase activity by the incubation.The increase of catalase activity was completely inhibited by cycloheximide and not by chloramphenicol. The increase of catalase activity was also markedly repressed by glucose, the repression not being eliminated by 3′, 5′-adenosine monophosphate.Microbody-like granules were detected cytochemically in the glucose-grown cells, but the increase of catalase content was not closely related to the appearance of microbody-like granules.

A general theory of wave energy in a plasma is developed in terms of a linear response of the field intensity to an externally applied infinitesimal disturbance. The theory is applicable to any situations, including the case when the conventional definition becomes invalid. An external disturbance can cause both frequency shift and amplitude change of the wave, and the sign of the wave energy in general depends on their relative importance and hence on the external disturbance. This feature is illustrated for the case of a cold-electron and cold-beam system. For the case when the dielectric function has a small anti-hermitian part, the conventional definition of the wave energy is recovered except for a special case where the frequency shift predominates over the amplitude change.

Effect of finite perpendicular extent of a cold relativistic electron beam on the two-stream instability excited in a warm plasma is investigated. It is shown that if the beam density profile is sufficiently slowly-varying the fastest growing modes are deeply trapped in the beam region and have growth rates comparable to the maximum growth rate of the usual two-stream instability by a uniform beam. The trapping is due to the frequency downshift of the space-charge wave below the Bohm-Gross frequency in the beam region. Both the dispersion relation analysis based on the WKB approximation and the eigenvalue analysis are presented.

The equilibrium properties of a rotating, non-neutral ion layer are examined within the framework of a steady-state Vlasov-Maxwell equations with a monoenergetic, single-canonical angular momentum distribution function. The analysis is carried out assuming that the ion layer is thin and the strength parameter of the ion layer v is much smaller than unity. As the ion layer becomes colder and colder, the influence of the self-fields on the radical thickness of the layer becomes more and more significant and can be large even though v<

A two-fluid energy principle is developed that leads to sufficient conditions for the low frequency stability of an axisymmetric, field-reversed ion ring immersed in a dense, background plasma. It is assumed that the ion ring is described as the rigidly rotating fluid with finite temperature while the background plasma as the stationary fluid. The stability condition is approximately given by the potential energy W (ξ p ,ξ b )>0, where ξ p and ξ b are the displacements of the ring and the background plasma, respectively. As an application, the stability condition for kink modes of a long ion layer immersed in a cold background plasma is examined in detail in order to compare the existing theories with the present theory.

The activity of catalase (EC 1.11.1.6) in Escherichia coli was profoundly repressed by growth with such substrates as glucose, mannose, galactose, ribose, glycerol, and pyruvate. The low catalase activity of the cells grown with glucose increased about twice when the cells were incubated with phosphate buffer containing yeast extract for 2hr. This increase of catalase activity was enhanced by continuous addition of H2O2 during the incubation. The increase of catalase activity was completely inhibited by chloramphenicol and Puromycin. The synthesis of catalase induced by H2O2 was repressed by glucose, and the repression was not eliminated by cyclic-AMP.

When 18-8 stainless steel is soaked in sea water, a local attack is formed by adhesion of microbes comparatively in a short time. In order to investigate the effects of corrosion defects on the fatigue strength of this material, we carried out the rotating beam fatigue tests of plain specimens and notched specimens with stress concentration factor, α=2.0, 3.3, 4.9, which were soaked in sea water for 3 months, 6 months and 12 months.The results obtained are as follows.(1) The fatigue limit of plain specimens and that of notched specimens with α=2.0 and 3.3 are on the decrease with the soaked periods shortened. The lowering ratio during the 12 months stood at 33%, 27% and 19%, respectively.(2) The corrosion defects in the order of crack, pin hole, line and pit have a deteriorative influences upon the fatigue strength.(3) The lowering of fatigue limit of notched specimens with α=4.9 is not recognized, for this is the strength with nonpropagating crack.(4) In the case of notched specimens with α=2.0 and 3.3 notch strengthening is found out, because of formation of martensite by plastic deformation at the notch root.

The penetration of an ordinary wave into an infinite magnetoplasma slab is calculated by adopting the image-metal technique in treating the electrons reflected at the plasma boundaries. After general expressions are derived, the wave frequency is assumed to be near the electron cyclotron frequency because the influence of the thermal motion of electrons is remarkable only for this case. It is found that the evanescent wave penetrates deeply into the slab compared with the case of a cold plasma, and the size effect appears due to the increase of the wave reflection at the plasma-vacuum boundary. The absorptive power due to collisions, evaluated for the limiting case of infinite thickness of the slab, is much larger than the value for a cold plasma and shows the surface effect. These two effects become more noticeable for the higher density and higher temperature of the plasma.

The physical picture for the anomalous propagation of an ordinary wave at frequency near but below the electron cyclotron is discussed on the basis of the single-electron equation of motion in the magnetostatic and the wave fields. It is shown that the anomalous propagation originates from the forces along and across the magnetostatic field. The perpendicular force deflects the electrons and gives the density perturbation which contributes to the anomalous propagation, as shown by Fried. It is found, however, that the parallel forces connected with the gyration of the unperturbed motion also contribute to the anomalous propagation and accompany no density perturbation.

Aerobically grown cells of Escherichia coli contained several times as much cytochrome b1, cytochrome d, and protoheme as anaerobically grown cells. The activity for the synthesis of δ-aminolevulinic acid (ALA) from succinate and glycine was remarkably higher in aerobically than in anaerobically grown cells. Incubation of anaerobically grown cells for 4hr with ALA under either aerobic or anaerobic condition resulted in the synthesis of protoheme, but the aerobic incubation was more favorable for the heme formation. By prolonged aeration of anaerobically grown cells with ALA, porphyrins were accumulated inside and outside of the cells. If casamino acids were supplemented to the incubation mixture containing ALA, the aerobic protoheme formation was much more pronounced, and the heme synthesis was partly inhibited by chloramphenicol and by puromycin. Accompanied with the formation of protoheme by the aerobic incubation of anaerobically grown cells, a cytochrome-type pigment, which could be reduced by succinate or NADH and oxidized by air, accumulated in the cells. The reduced spectrum of the pigment showed peaks identical with those of cytochrome b1, but the shape of the absorption curve was not the same as that of the cytochrome.These results, and previous findings, reveal that the effect of oxygen on the formation of heme and cytochrome in E. coli is manifold; oxygen enhances (1) the formation of enzymes for succinyl-CoA synthesis, (2) formation of enzymes in some step between ALA and protoheme, (3) the reaction of preformed enzymes in some step between ALA and protoheme (probably the conversion of coproporphyrinogen to protoporphyrin), and possibly (4) the formation of ALA synthetase. In addition, oxygen may affect the formation of apoprotein moiety of cytochromes.

In the Indian Ocean, mid-depth oxygen minimum zones (OMZs) occur in the Arabian Sea and the Bay of Bengal. The lower part of the Arabian-Sea OMZ (ASOMZ; below 400 m) intensifies northward across the basin; in contrast, its upper part (above 400 m) is located in the central/eastern basin, well east of the most productive regions along the western boundary. The Bay-of-Bengal OMZ (BBOMZ), although strong, is weaker than the ASOMZ. To investigate the processes that maintain the Indian-Ocean OMZs, we obtain a suite of solutions to a coupled biological/physical model. Its physical component is a variable-density, 6 1 2 -layer model, in which each layer corresponds to a distinct dynamical regime or water-mass type. Its biological component has six compartments: nutrients, phytoplankton, zooplankton, two size classes of detritus, and oxygen. Because the model grid is non-eddy resolving (0.5°), the biological model also includes a parameterization of enhanced mixing based on the eddy kinetic energy derived from satellite observations. To explore further the impact of local processes on OMZs, we also obtain analytic solutions to a one-dimensional, simplified version of the biological model. Our control run is able to simulate basic features of the oxygen, nutrient, and phytoplankton fields throughout the Indian Ocean. The model OMZs result from a balance, or lack thereof, between a sink of oxygen by remineralization and subsurface oxygen sources due primarily to northward spreading of oxygenated water from the Southern Hemisphere, with a contribution from Persian-Gulf water in the northern Arabian Sea. The northward intensification of the lower ASOMZ results mostly from horizontal mixing since advection is weak in its depth range. The eastward shift of the upper ASOMZ is due primarily to enhanced advection and vertical eddy mixing in the western Arabian Sea, which spread oxygenated waters both horizontally and vertically. Advection carries small detritus from the western boundary into the central/eastern Arabian Sea, where it provides an additional source of remineralization that drives the ASOMZ to suboxic levels. The model BBOMZ is weaker than the ASOMZ because the Bay lacks a remote source of detritus from the western boundary. Although detritus has a prominent annual cycle, the model OMZs do not because there is not enough time for significant remineralization to occur.

A CO-binding hemochrome was accumulated in Escherichia coli cells, when intracellular heme concentration was increased by aerobic incubation of resting cell suspensions with ALA. Reduced minus oxidized difference spectrum of the hemochrome showed peaks at 560, 530, and 430 nm and a shoulder at 575 nm. The peaks of CO reduced minus reduced difference spectrum were located at 572, 540, and 422 nm. The CO spectrum was similar to but not identical with the spectrum of cytochrome o, a known terminal oxidase in E. coli. SDS-polyacrylamide gel electrophoresis of the CO-binding hemochrome showed its molecular weight to be about 33,000. The hemochrome in crude cell-free extracts was oxidized by aeration and reduced by the addition of succinate or NADH. The reduction by succinate was inhibited by inhibitors of succinate dehydrogenase [EC 1.3.99.1], and the reduction by NADH was inhibited by 2-heptyl-4-hydroxy-quinolin-N-oxide, which is an inhibitor of electron transport in E. coli cells.

Ocean general circulation models (OGCMs) have long been used to investigate oceanic circulations and their variation with various spatial and temporal scales. Mesoscale eddies, which diameters are about 100 km, should be resolve in order to reproduce not only basin-scale circulation but also eddy activities and proper path of western boundary currents. They also play an important role to meridional transport of heat and momentum. Recently, an eddy-resolving OGCM simulation with 0.1/spl deg/ horizontal grid spacing in the North Atlantic basin suggests that OGCM should have the grid spacing of the order of 0.1/spl deg/ or finer. Although computational resource was not enough to execute global eddy-resolving simulation, the Earth Simulator (ES) with 40 Tflops peak performance, which currently is the fastest massive parallel computer for general purpose, changed the computational environment. The ES and OGCM highly tuned for the ES provide us the opportunities to execute several decadal integrations of the eddy-resolving OGCM simulation in the global domain. In This work, successful outcomes and advanced visualizations from a series of eddy-resolving simulations in the world ocean: a 50 year spin-up run, hindcast run from 1950 to 2003 and tracer run incorporated with chlorofluorocarbons (CFCs), are reported.

By means of the two‐fluid model, the kink stability of a long thin field‐reversed ion layer immersed in a dense low‐temperature background plasma is studied theoretically. The two‐fluid variational quadratic form with the assumption of rigid displacements in the radial direction yields a new kink stability condition that includes the effect of the nonzero real frequency of the modes, which results from the inertia of the ion layer. Although it was neglected in previous analyses, this effect is essential to explain the numerical results of Harned [Phys. Fluids 25, 1915 (1982)]. As the ratio of the density of the background plasma to that of the ion layer increases, this new kink stability condition reduces to the conventional condition. The physical mechanism for the kink instability is discussed by means of an analogy with the electrostatic two‐stream instability.

Standard magnetohydrodynamic (MHD) equations are extended to include arbitrary equilibrium flows and multiple fluids and an equivalent variational form is developed. This system is appropriate for the study of stability in any multifluid flowing plasma, e.g., allowing for arbitrary poloidal and toroidal equilibrium flows and accounting for the Hall terms. The variational formalism is applied to the particular case of the internal tilting instability in a field‐reversed configuration (FRC). A solution by means of the Rayleigh–Ritz technique leads to the dispersion relation, from which the growth rate and marginal stability conditions are determined. A new stability regime is found for sufficiently elongated FRC’s, arising as a consequence of the Hall effect. These results are compared with experiment and related theory.