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Soliton formation in Earth’s mesosphere plasma is described. Nonlinear acoustic waves in plasmas with two-temperature ions and a variable dust charge where transverse perturbation is dealt with are studied in bounded spherical geometry. Using the perturbation method, a spherical Kadomtsev–Petviashvili equation that describes dust acoustic waves is derived. It is found that the parameters taken into account have significant effects on the properties of nonlinear waves in spherical geometry.

The nonlinear dust acoustic waves in dusty plasmas with two temperature electrons and the combined effects of bounded spherical geometry and the transverse perturbation are studied. Using the perturbation method, a spherical Kadomtsev-Petviashvili (SKP) equation that describes the dust acoustic waves is deduced.

Dust-acoustic solitary waves in unmagnetized dusty plasma whose constituents are inertial charged dust grains, Boltzmannian electrons and nonthermal ions have been investigated by taking into account finite dust temperature. The pseudopotential has been used to study solitary solution. The existence of solitary waves having negative potential is reported.

In the Li-ion technology, the diffusion of Li in the electrode is often limited by the quality of interfaces. Two synthetic approaches are proposed to develop the transition metal phosphides (TMP)/electrolyte interface. The first route consists in the preparation of nickel nanopowder by solution phase synthesis, and the second is based on the electrochemical synthesis of nickel nanorods in a template followed by vaporization of phosphorous. In the former, the nanosized metallic particles are foreseen to be used as starting nanomaterial to directly react with phosphorous agents (P or Li3P) during the cycling of the lithium battery. A preliminary electrochemical test of the NiPx nanorods/Li half-cell shows the feasibility of the use of such nanostructured TMP electrode in a Li battery.

Soliton formation in plasma is addressed. Nonlinear acoustic waves in plasma where the combined effects of bounded spherical geometry and the transverse perturbation are dealt with, in two-temperature electron plasma are studied. Using the perturbation method, a spherical Kadomtsev-Petviashvili equation (SKP) that describes the ion acoustic waves is derived. The plasma is modeled by a kappa distribution function for both electrons components as found in Saturn’s magnetosphere. It is found that parameters taken into account have significant effects on the properties of nonlinear waves. The model is applied to Saturn’s magnetosphere, where two temperature superthermal electrons are present. Hence, ion acoustic waves are deduced for three regions, namely, the inner, the intermediate and the outer Saturn’s magnetosphere. We point out, that this work has been motivated by recent observations of Saturn’s magnetosphere.

Plasma expansion and soliton formation in laser created plasma are addressed. Nonlinear acoustic waves in plasmas where the combined effect of trapped and nonthermal electrons are dealt with, in plasma expansion are studied. Using the perturbation method, a modified Korteweg-de Vries equation (mKdV) that describes the ion acoustic waves is derived. The plasma is modeled by a Cairns distribution function for nonthermal electrons combined with Gurevich distribution function for the trapped electrons. It is found that parameters taken into account have significant effects on the properties of nonlinear waves as well as on plasma expansion into vacuum. We point out, that this work has been motivated by space and laboratory plasma observations of plasmas containing energetic particles, combined with trapped particles. Furthermore, this study is of interest in the context of the investigation of mono-energetic ion beams from intense laser interactions with plasmas.

Plasma expansion and soliton formation in laser created plasma are addressed. Nonlinear acoustic waves in plasma where the combined effect of trapped and non-thermal electrons are dealt with, in plasma expansion are studied. Using the perturbation method, a modified Korteweg–de Vries equation (mKdV) that describes how the ion acoustic waves (IAW) are derived. The plasma is modeled by a Cairns distribution function for non-thermal electrons combined with Gurevich distribution function for the trapped electrons. It is found that parameters taken into account have significant effects on the properties of nonlinear waves as well as on plasma expansion into vacuum. We point out, that this work has been motivated by space and laboratory plasma observations of plasmas containing energetic particles, combined with trapped particles. Furthermore, this study is of interest in the context of the investigation of mono-energetic ion beams from intense laser interactions with plasmas.

Magnetosonic waves are investigated in plasma by using the reductive perturbation technic. Analytical solution of KP equation has been studied numerically and graphically. It is noticed that for stronger magnetic field the nonlinearity decreases.

In order to establish a design rule of the plasma reactors, a fundamental investigation was carried out. The results show that important points of the design criteria were flow speed of gas and power input to the discharge tubes. An engineering model of plasma reactor for 100 kVA diesel engine generating system was designed, constructed and tested. The reactor is composed of 3 blocks, 30 discharge tubes with 1 m long and they are driven by a high voltage inverter power source. The test results show that the fundamental data were applicable to the engineering model reactor and the required energy yield of NO oxidation process was almost attained. A scale up rule has also been confirmed

Fusion performance of reversed shear discharges with an {ital L}-mode edge has been significantly improved in a thermonuclear dominant regime with up to 2.8 MA of plasma current in the JT-60U tokamak. The core plasma energy is efficiently confined due to the existence of persistent internal transport barriers formed for both ions and electrons at a large minor radius of r/a{approximately}0.7 near the boundary of the reversed shear region. In an assumed deuterium-tritium fuel, the peak fusion amplification factor defined for transient conditions involving the dW/dt term would be in excess of unity. {copyright} {ital 1997} {ital The American Physical Society}

The nonlinear evolution of acoustic wave in unmagnetized dusty plasma in which electrons are completely depleted (corresponding to F Saturn ring) was shown to obey the Davey-Stewartson I equation which admits so called dromion solutions. The importance of these two dimensional localized solutions for recent satellite observations of wave structures in the day side polar cap regions was discussed.

We study the possibility of formation of voids in y Lorentzian plasmas containing of dust particles obeying to vortex‐like velocity distribution. The size of the void is found to be ion spectral index dependent.

The nonlinear evolution of dust acoustic wave in magnetized dusty plasmas is shown to obey the Davey‐Stewartson I equation, which admits the so called dromion solutions.

Recent lower hybrid current drive (LHCD), and heating (LHH) experiments on JT-60 are reported. The current drive product of neRpIRF approximately 12.5*1019 m-2 MA was achieved at the LH power of approximately 4.5 MW, and the CD efficiency, the energy confinement, the global power balance and the heat load on divertor plates were investigated in high power LHCD plasmas. Nearly steady state H-mode discharges were found during LHCD with two different frequency injections. Sawtooth suppression in NB heated plasmas by LHCD have shown an improvement in confinement near the plasma center. Parametric instabilities in LH heating experiments were significantly reduced by increasing the plasma current, and the stored energy increased linearly with heating power of up to approximately 9 MW at ne approximately 7*1019 m-3 and Ip=2.75 MA. Parametric instabilities near the plasma edge in the ion heating regime were also reduced in peaked density plasmas produced by pellet injection and LH waves increased the central plasma pressure at ne(0) > 1.4*1020 m-3.

The investigation of the formation of non‐linear coherent structures in dusty plasmas taking into account the dust size and non‐thermal ion distributions is conducted. Conditions of the existence of solitons in terms of the Mach number, concentration of non‐thermal ions, dust charge and the permeability of the grains are evaluated.

Summary form only given. In this work, the nonlinear evolution of dust acoustic wave in magnetized dust-ion plasma was investigated. The two component dusty plasma considered is valid as long as n e0 <

Emphases in JT-60 experiments are placed on (1) lower-hybrid (LH) current drive characteristics with a multi-junction type launcher, and (2) the confinement study with combination of neutral beam injection LH current drive and pellet injection. The new multi-junction LH launcher provides a sharp N/sub /// spectrum with high directivity for N/sub ///=1-3.4. The current drive efficiency and the radial distribution of high energy electron production show clear correlation with injected N/sub ///: the current drive efficiency has the maximum at low N/sub ///( approximately 1.3) while flattening of plasma current is more effective in large N/sub ///. A broad radial distribution of high energy electron current and approximately 30% reduction in sawtooth inversion radius were obtained by high N/sub /// ( approximately 2.5) LH injection. To fully suppress the sawtooth activity, low N/sub /// ( approximately 1.3) injection was found to be more effective. Improved energy confinement has been obtained with hydrogen pellet injection. Energy confinement time was enhanced up to 40% relative to usual gas fuelled discharges. The discharge has a strongly peaked electron density profile with ne(0)/(ne) approximately 5 and ne(0) approximately 2.0*1020 m-3. The improved discharges are characterized by a strongly peaked pressure profile within the q=1 magnetic surface, and degrades when a large sawtooth recovers or the pressure gradient may reach a critical value. When large (3 mm, 4 mm) and fast (2.2 km/s) pellets were injected, 30% energy confinement improvement was obtained even during the NB heating of 14 MW. Further investigations of IDC characteristics have been made. The oxygen impurity lines from the main plasma and the main radiative loss drop first. Then the plasma stored energy starts to rise. The particle recycling is reduced around the main plasma, and is localized in the neighborhood of the X-point with a time lag of approximately 0.2 sec. Eventually the discharge shows a significant remote radiative cooling power at the divertor region.