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Mixed cationic Ca2+/Na+(Mg2+) polyphosphates, regarded as potential biocomposite fillers, were fabricated by solid-state reactions. Most of them demonstrated low solubility (assessed also by the Glasser and Jenkins approach) from 1 ± 0.2 g/L for Ca(PO3)2 to 5 ± 0.4 g/L for NaCa(PO3)3 and 50 ± 2 g/L for soluble phase of NaPO3. Liquid-state NMR of the soluble part of polyphosphates gave the degree of polymerization of their chains ranging from 10 to 30 for NaCa(PO3)3 and ca. 1000 monomeric units for NaPO3.

In this study, field electron emission current uniformity and stability of the well-aligned carbon nanotubes (CNTs) synthesized in methanol has been investigated by using the scanning probe field emission current (SPFEC) measurement system. The effect of crystallinity of the well-aligned CNT is also discussed.

Sumitomo Electric successfully developed drastically innovative Bi-2223 (DIBSCCO), namely, commercially produced Bi2223 long length wires using the controlled over pressure sintering (CT-OP) with unique properties quite different from conventional silver sheathed BSCCO wires. CT-OP prevented pores occurring in BSCCO cores, so it reformed conventional Bi2223 wires to DI-BSCCO with excellent properties of higher critical currents, stronger mechanical strength and better durability against temperature rise in cryogen such as pressurized liquid nitrogen. It enhanced the critical current by 50 percent conventional wires sintered in normal atmospheres. Critical tensile stress was also improved by more than 150 percent. Any ballooning defects and degradation of critical current, one of the critical problems for the conventional BSCCO wires, were not found in full length of several km long DI-BSCCO tapes after 24 hours immersion into 1MPa liquid nitrogen.

A magnetic sensor, constructed of bulk Bi-Pb-Sr-Ca-Cu-O (BPSCCO), was fabricated by use of the shock compaction method, employing a propellant gun-system, and then sintered under through use of an electronic furnace. The specimen as a magnetic sensor was maintained in the superconducting state at 77.4 K, under a current density J of approximately 40 A/cm2 in the absence of an excitation magnetic field Bex. The superconducting state was then broken and the specimen exposed to a Bex value of 40?10?4 T. That is, the resistance Rmeas of the specimen occurred when exposed to 40?10?4 T under a constant J of 40 A/cm2. The magnetic sensitivity S of the specimen was approximately 13 %/(10?4 T) over the range of measurement of the magnetic field Bmeas from 0 to ?5?10?4 T, under a constant 40?10?4 T for the value of Bex, being approximately 13 times greater than that of a giant magnetoresistance (GMR) sensor. It was, consequently, determined that it was possible to apply the bulk BPSCCO specimen as a highly sensitive magnetic sensor.

We have investigated the structure and magnetization of Co2(Cr1−xFex)Al (0 ≤ x ≤ 1) and Co2FeSi full-Heusler alloy films deposited on thermally oxidized Si (SiO2) and MgO (001) single crystal substrates by ultra-high vacuum sputtering at various temperatures. The films were also post-annealed after deposition at room temperature (RT). Magnetic tunnel junctions with a full-Huesler alloy electrode were fabricated with a stacking structure of Co2YZ (20 nm)/Al (1.2 nm)-oxide/Co75Fe25 (3 nm)/IrMn (15 nm)/Ta (60 nm) and microfabricated using electron beam lithography and Ar ion etching with a 102 µm2 junction area, where Co2YZ stands for Co2(Cr1−xFex)Al or Co2FeSi. The tunnel barriers were formed by the deposition of 1.2 nm Al, followed by plasma oxidization in the chamber. The x-ray diffraction revealed the A2 or B2 structure depending on heat treatment conditions and the substrate, but not L21 structure for the Co2(Cr1−xFex)Al (0 ≤ x ≤ 1) films. The L21 structure, however, was obtained for the Co2FeSi films when deposited on a MgO (001) substrate at elevated temperatures above 473 K. The maximum tunnelling magnetoresistance (TMR) was obtained with 52% at RT and 83% at 5 K for a junction using a Co2(Cr0.4Fe0.6)Al electrode. While the junction using a Co2FeSi electrode with the L21 structure exhibited the TMR of 41% at RT and 60% at 5 K, which may be improved by using a buffer layer for reducing the lattice misfit between the Co2FeSi and MgO (001) substrate.

Recent progress in the physics and engineering design study for the modification programme of JT-60 is presented. In order to achieve a steady state high-β plasma operation, which is the dominant issue of this programme, physics design for the MHD control and the stability analysis is investigated. Engineering design and the R & D for the superconducting coils, irradiation shield are performed well towards the mission of programme.

A fully superconducting tokamak named JT-60SC is designed for the modification programme of JT-60 to enhance economical and environmental attractiveness in tokamak fusion reactors. JT-60SC aims at realizing high-β steady-state operation in the use of low radio-activation ferritic steel in a low ν* and ρ* regime relevant to the reactor plasmas. Objectives, research issues, plasma control schemes and a conceptual design for JT-60SC are presented.

The structural change between substitution-type ordered structures basically includes the competition of pairwise interactions, which can describe the stability of such structures. The purpose of this study is to investigate the frustration effect resulting from competition related to the L12 → D022 structural change in the Ni3Al0.52V0.48 alloy and to discuss the pattern bifurcation in the pseudobinary Ni3(Al, V) alloy. The present data obtained by transmission electron microscopy show that the change in microstructures during the structural change is characterized by the appearance and the subsequent annihilation of D022 regions in the L12 matrix. The final product of the structural change is the L12 single phase including topological defects, which is different from the equilibrium state known as the L12 + D022 checkerboard pattern. This indicates that the suppression of the L12 → D022 structural change occurs in this alloy. Such suppression can be explained as being due to an inability to accommodate the strain field in the vicinity of the L12/D022 boundaries when D022 precipitation occurs. The trigger of this inability is thought to be strong frustration originating from a small concentration deviation in the initial L12 matrix from the stoichiometry of the L12 structure. It is concluded that the formation of the L12 single phase as the final state, i.e. spontaneous L12 single crystallization, results from an effort by the alloy to accommodate the strain field, the occurrence of which is related to the frustration effect appearing during the L12 → D022 structural change.

JT-60U has conducted extensive experiments for 17 years to achieve equivalent break-even conditions and to establish the scientific and technological basis of ITER and future DEMO reactors such as SSTR. Two types of advanced scenarios, high βp H-mode (with weak positive shear) and RS mode (negative shear), are developed in JT-60U. High performance discharges are maintained by full non-inductive current drive, primary with neutral beam current drive. The results are quite promising in demonstrating principle of steady-state tokamak operation. The research clarified many important issues for future studies.

The bootstrap current is a plasma current associated with trapped particles in a toroidal plasma. Magnetic measurements, such as the surface voltage, the internal inductance, and the Faraday rotation, are consistent with the existence of the neoclassical bootstrap current in tokamaks. The neoclassical trapped-particle correction to the electrical conductivity is also systematically validated against experiments. These results support the assertion that the generalized Ohm's law along the magnetic field is valid, as predicted by the neoclassical transport theory, while the perpendicular transport deviates from the neoclassical transport theory.

The influence of the toroidal field ripple on global H-mode performance in JT-60U has been investigated. The ripple size was varied by changing the plasma volume. The ripple losses have been measured by monitoring the local heat load to the first wall and have been simulated by the Orbit Following Monte Carlo code. The global H factors are found to be not very sensitive to the ripple size when the net input power is corrected for the ripple-trapped and banana-drift losses. These results are confirmed by theoretical analysis of the ripple-induced transport coefficients at rho =0.9.

Based on recent progress in world tokamak research, the prospects of continuous operation of a tokamak fusion power reactor are discussed. Efficient steady state operation (Q>30) becomes feasible when a large fraction of the plasma current (>70%) is driven by the bootstrap current. Moderate current (Ip approximately 10-20 MA) and an enhanced confinement mode of operation are the key for efficient steady state operation. High magnetic fields (Bt=8-11T) and high Troyon factors ( beta N>3.5) are required to attain high beta p operation and a reasonably high fusion power density. Control of the current and edge pressure profiles is necessary for high beta N operation with a high bootstrap fraction. It is proposed that the Next Step Tokamak should be optimized for continuous operation as well as high current pulsed operation.

A method of power handling in tokamak power reactors using heavy impurity injection is discussed. In this method, iron powder is injected together with the fuel gas through holes in the divertor plate, which leads to strong impurity radiation from the divertor plasma. The method is effective in establishing a dense and cold plasma and in reducing the heat flux to the divertor plate under the conditions of a power reactor. In a simulation with a 2-D divertor code it is shown that the injected heavy impurity does not flow into the main plasma because of strong friction forces between impurity and fuel ions

The energy confinement properties of JT-60 during Ohmic and neutral beam heated discharges are analysed on the basis of the heat pinch model proposed by Callen and Cordey. The feature of temperature profile consistency during variation of the density profile sets an important constraint for the heat pinch term. A heat pinch term proportional to neBp seems to be consistent with the experimental observation. A transport model is proposed which reproduces quite well the parameter dependence of the JT-60 experimental data. The formation of an edge temperature pedestal during the H-mode is observed with this model when the edge convective energy loss is significantly reduced.

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.

A concept of a steady state tokamak fusion reactor based on the bootstrap current is presented. Operation at high poloidal beta (?p ? 2.0) and high q (4?5) with a relatively small limit on ??p (< 0.5) makes it possible to drive a bootstrap current constituting up to 70% of the total plasma current without exceeding the Troyon beta limit. The rest of the plasma current can be driven by the high energy neutral beam with an energy multiplication factor Q of 30. Energy confinement scaling laws predict that the reactor condition is attainable by increasing the major radius up to 9 m in such a high ?p and high q plasma at a relatively low plasma current (12 MA) with a confinement enhancement factor of 2 compared with the L-mode scaling. This reactor has a reasonable size (Vp = 1500 m3) and fusion output power (2.5 GW) and is consistent with present knowledge regarding tokamak plasma physics, namely the Troyon limit, the energy confinement scalings, the bootstrap current and the current drive efficiency (neutral beam current drive with a total power of 70 MW and a beam energy of 1 MeV) with good prospects for the formation of a cold and dense divertor plasma.

The Nuclear Fusion Award ceremony for 2009 and 2010 award winners was held during the 23rd IAEA Fusion Energy Conference in Daejeon. This time, both 2009 and 2010 award winners were celebrated by the IAEA and the participants of the 23rd IAEA Fusion Energy Conference. The Nuclear Fusion Award is a paper prize to acknowledge the best distinguished paper among the published papers in a particular volume of the Nuclear Fusion journal. Among the top-cited and highly-recommended papers chosen by the Editorial Board, excluding overview and review papers, and by analyzing self-citation and non-self-citation with an emphasis on non-self-citation, the Editorial Board confidentially selects ten distinguished papers as nominees for the Nuclear Fusion Award. Certificates are given to the leading authors of the Nuclear Fusion Award nominees. The final winner is selected among the ten nominees by the Nuclear Fusion Editorial Board voting confidentially. 2009 Nuclear Fusion Award nominees For the 2009 award, the papers published in the 2006 volume were assessed and the following papers were nominated, most of which are magnetic confinement experiments, theory and modeling, while one addresses inertial confinement. Sabbagh S.A. et al 2006 Resistive wall stabilized operation in rotating high beta NSTX plasmas Nucl. Fusion 46 635–44 La Haye R.J. et al 2006 Cross-machine benchmarking for ITER of neoclassical tearing mode stabilization by electron cyclotron current drive Nucl. Fusion 46 451–61 Honrubia J.J. et al 2006 Three-dimensional fast electron transport for ignition-scale inertial fusion capsules Nucl. Fusion 46 L25–8 Ido T. et al 2006 Observation of the interaction between the geodesic acoustic mode and ambient fluctuation in the JFT-2M tokamak Nucl. Fusion 46 512–20 Plyusnin V.V. et al 2006 Study of runaway electron generation during major disruptions in JET Nucl. Fusion 46 277–84 Pitts R.A. et al 2006 Far SOL ELM ion energies in JET Nucl. Fusion 46 82–98 Berk H.L. et al 2006 Explanation of the JET n = 0 chirping mode Nucl. Fusion 46 S888–97 Urano H. et al 2006 Confinement degradation with beta for ELMy HH-mode plasmas in JT-60U tokamak Nucl. Fusion 46 781–7 Izzo V.A. et al 2006 A numerical investigation of the effects of impurity penetration depth on disruption mitigation by massive high-pressure gas jet Nucl. Fusion 46 541–7 Inagaki S. et al 2006 Comparison of transient electron heat transport in LHD helical and JT-60U tokamak plasmas Nucl. Fusion 46 133–41 Watanabe T.-H. et al 2006 Velocity–space structures of distribution function in toroidal ion temperature gradient turbulence Nucl. Fusion 46 24–32 2010 Nuclear Fusion Award nominees For the 2010 award, the papers published in the 2007 volume were assessed and the following papers were nominated, all of which are magnetic confinement experiments and theory. Rice J.E. et al 2007 Inter-machine comparison of intrinsic toroidal rotation in tokamaks Nucl. Fusion 47 1618–24 Lipschultz B. et al 2007 Plasma–surface interaction, scrape-off layer and divertor physics: implications for ITER Nucl. Fusion 47 1189–205 Loarer T. et al 2007 Gas balance and fuel retention in fusion devices Nucl. Fusion 47 1112–20 Garcia O.E et al 2007 Fluctuations and transport in the TCV scrape-off layer Nucl. Fusion 47 667–76 Zonca F. et al 2007 Electron fishbones: theory and experimental evidence Nucl. Fusion 47 1588–97 Maggi C.F. et al 2007 Characteristics of the H-mode pedestal in improved confinement scenarios in ASDEX Upgrade, DIII-D, JET and JT-60U Nucl. Fusion 47 535–51 Yoshida M. et al 2007 Momentum transport and plasma rotation profile in toroidal direction in JT-60U L-mode plasmas Nucl. Fusion 47 856–63 Zohm H. et al 2007 Control of MHD instabilities by ECCD: ASDEX Upgrade results and implications for ITER Nucl. Fusion 47 228–32 Snyder P.B. et al 2007 Stability and dynamics of the edge pedestal in the low collisionality regime: physics mechanisms for steady-state ELM-free operation Nucl. Fusion 47 961–8 Urano H. et al 2007 H-mode pedestal structure in the variation of toroidal rotation and toroidal field ripple in JT-60U Nucl. Fusion 47 706–13 Günter S. et al 2007 Interaction of energetic particles with large and small scale instabilities Nucl. Fusion 47 920–8

To improve the mechanical properties of silver-sheathed BSCCO wire, the laminated BSCCO wires with stainless steel were made under some experimental conditions. The dependence of the stainless steel thickness and the dependence of the pre-tension of stainless steel tapes on the laminated BSCCO were investigated by mechanical tests (tensile test at 77 K and RT and double-bending test at RT) using short samples. Due to the difference of the coefficient of thermal expansion (CTE) and the relaxation to equilibrium after removing the total pre-tension of no laminated BSCCO (insert tape) and stainless steel tapes, the residual axial compressive strain applies to an insert tape after the lamination process. A high compressive strain up to the compressive yield of the silver-alloy is so useful for improvement of the mechanical properties of BSCCO wire. Measurement results were approximately the same as the simple model calculated from the residual strain applied to an insert tape by the difference of CTE and pre-tension. The stainless-steel-laminated BSCCO wire 'Type HT-SS' has been able to be achieved over 500 MPa at 77 K by increasing stainless steel thickness and the residual axial compression for an insert tape. The developed tough DI-BSCCO has a higher hoop force to compare with YBCO-coated conductor using Hastelloy substrates under the same circumstances such as magnetic field, winding diameter and transport current.

Sumitomo Electric has been developing the silver-sheathed Bi2223 multi-filamentary wires since the discovery of Bi-based superconductors. DI-BSCCO is the high performance wires produced using the controlled-overpressure (CT-OP) sintering technique. The present commercial DI-BSCCO can provide the uniform high critical current, Ic, up to 180 A with length over 2000 m, and recently 200 A were succeeded to be obtained by the same kind of 1000 m length wires, resulting from the improvement and control of the microstructure in Bi2223 multi-filaments. The short trial wires of several meters have exhibited the highest Ic over 240 A at 77K in self-field (corresponding to 580 A per 1 cm-width). Besides, the optimization of carrier density after CT-OP led to further enhancement of Ic, reached 250 A. All the derivative products also have uniform critical current properties over entire length even after lamination with the reinforcing metals. The performances of DI-BSCCO can meet the growing needs for various application of high temperature superconductor like high in-field applications, such as magnets and motors. The recent progress in transport properties of commercial DI-BSCCO and R&D short trial wires is shown.

The chain dimensions of free and immobilized polysulfobetaine in aqueous solution at various salt concentrations were investigated by size-exclusion chromatography with multiangle light scattering and neutron reflectivity measurement, respectively. The dependence of the z-average mean square radius of gyration ( z1/2) on the weight-average molecular weight (Mw) of free poly(3-(N-2-methacryloyloxyethyl-N,N-dimethyl)ammonatopropanesulfo-nate) (MAPS) in aqueous solution at salt concentrations of 74, 100, 200, and 500 mM was described by the perturbed wormlike chain model using the chain stiffness parameter λ−1 the molar mass per unit contour length ML, and the excluded volume effect B. B increased from 0 to 1.8 nm with increasing salt concentration to 500 mM due to the screening of attractive electrostatic interaction between ammonium cations and sulfonyl anions by salt ions. The swollen structure of the poly(MAPS) brush in D2O changed from a shrunken state to a relatively extended state with increasing salt concentration from 0 to 500 mM NaCl/D2O solution. The thickness of the swollen poly(MAPS) brush in 500 mM NaCl/D2O was 9.0 times greater than 2 z1/2 of free poly(MAPS) due to high osmotic pressure generated by the excluded volume effect of densely grafted polymer chains.

This paper describes a surface crack growth simulation using a new mesh generation technique. The generated mesh is constituted of all hexahedral elements. Hexahedral elements are suitable for an analysis of fracture mechanics parameters, i.e. stress intensity factor. The advantage of a hexahedral mesh is good accuracy of an analysis and less number of degrees of freedoms than a tetrahedral mesh. In this study, a plural crack growth simulation is computed using the hexahedral mesh and its distribution of stress intensity factor is investigated.

High Ic in DI-BSCCO has been demonstrated even in high temperature up to 90K and parallel magnetic field up to 200 mT. This performance is advantageous especially to power cables cooled with pressurized liquid nitrogen, where current and temperature fluctuates in real operation. Recent development has updated the highest Jc at 77K, self-field to 630 A/mm2 in a R&D tape. The evaluation by a scanning magnetic microscope has demonstrated the highest Jc of 900 A/mm2 at the midst of a tape which has Ic of 200 A. This property promises innovative Ic more than 300 A in future DI-BSCCO.

High-pressure behaviour of Ta3Si intermetallic compound was investigated by shock compression and static compression methods. Superconducting phase with TC = 9.3 K was found in the sample shocked to 50-61 GPa, however most of the shock recovered sample indicated the starting stable phase with the Ti3P-type structure. The new superconducting phase was not obtained from static compression up to 15 GPa and 800 ?C. Bulk modulus of Ta3Si with the Ti3P-type structure was determined to be K0 = 246(4) GPa. The present results suggest that a rapid phase transformation occurred during shock compression, but most of the high-pressure phase was reverted to the stable phase in the decompression process.

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Controlled overpressure (CT-OP) processing eliminates pores and heals cracks, which densifies the Bi2223 filaments and increases the critical current of Ag-sheathed Bi2223 wire. High current capacity wires with critical current values around 210 A at 77 K and self-field have been achieved. The enhancement of the current capacity seems to be due to reducing the weak links between Bi2223 grains and improving the flux pinning. In order to understand the mechanisms for transport critical current in Bi2223 wires, the dependence of the critical current on magnetic field and temperature has been investigated. The critical current is measured as a function of the perpendicular and parallel magnetic fields, up to 12 T, at temperatures ranging from 4.2 to 90 K. These results indicate that higher critical current is associated with highly textured and well connected Bi2223 grains. To further improve a critical current of Bi2223 wires, it is necessary to decrease the misalignment angle and reduce the fraction of Bi2212 and secondary phases.

The highest Ic of a latest DI-BSCCO® tape, which is the high performance silver sheathed Bi2223 tapes produced with CT-OP® technique, has reached 210 A (500A/cm-width) at 77K, self-field. The wide-range measurement of Ic using temperature variable system also has proved the highest performance at each temperature and external magnetic field. The combination of CT-OP® and stainless steel lamination techniques has concurrently obtained Ic higher than 200 A, rated tensile stress more than 300 MPa and rated tensile strain more than 0.4 % at 77 K. A texture analysis using synchrotron radiation has revealed explicit correlation between Jc and c-axis misalignment angle in CT-OP® processed tapes.

The relation between Mirnov coil signals and the current perturbation on the rational surface is examined analytically by using the approximate Green's function for the case of large aspect ratio circular tokamaks. Satellite island formation, phase modulation effect due to the poloidal variation of the field line pitch, and the shift effect of the plasma column with respect to the center of the vacuum chamber are examined. The detectability of these effects from Mirnov coil signals is discussed for TFTR.

Young's modulus and the Delta E effect of Fe-Pd Invar alloys have been investigated. The Delta E effect at room temperature exhibited a similar concentration dependence of the longitudinal linear magnetostriction. The temperature dependence of Young's modulus was analogous to that of Fe-Ni and Fe-Pt Invar alloys, namely Young's modulus increased below the Curie temperature with increasing temperature. The variation of Young's modulus at room temperature with Pd content showed a minimum around 30% Pd.

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.

Initial ohmic heating experiments in JT-60 were performed for a three month period of April-June 1985. A maximum plasma current of 1.6 MA was obtained for both divertor and limiter discharges. Low-q discharges of qeff=2.5 and high density discharges of 4.8*1019 m-3 in line-averaged density were obtained in the divertor configuration. In divertor discharges radiated loss from the main plasma can be kept at 20-30% of the ohmic input.

From June to October 1987, JT-60 achieved fusion product (ne(0). tau E*.Ti(0)) of 6*1019 m-3.keV.s with hydrogen plasma at plasma current of 2.8 to 3.1 MA with neutral beam power of approximately 20 MW. The central electron density of 1.3*1020 m-3 was obtained at plasma current of 3 MA with 13 approximately 20 MW neutral beam power and the confinement time reached 0.14-0.18 s. An offset linear scaling law like the Shimomura-Odajima scaling on confinement time will be able to reproduce experimental data better than that of the Goldston type scaling. With low beam energy injection approximately 40 keV, confinement degradation was found. Many short periods (0.05 approximately 0.1 s) of H-mode phase were found in outside X-point divertor discharges with NB or NB+RF(LH or IC) heating power above 16 MW. However, improvement in energy confinement time was limited to 10 %. The ballooning/interchange stability analyses were also made for the outside X-point divertor equilibrium in connection with H0-phase capability. Heating powers of 9.5 MW and 1.9 MW were obtained by LHRF, ICRF injection, respectively. In combined LHRF and NB heating, the incremental energy confinement time of 0.064 s was obtained, which is the same level of that of NB heating only. In combined NB and on-axis ICRF heating of low ne discharge, an incremental energy confinement time of 0.21 s was obtained, which is three times as long as those of NB or ICRF heating only. High energy beam ions were accelerated by ICRF in the central region of the plasma.

The frequency shift of a self-oscillating caesium vapour magnetometer, caused by misalignment of the light direction with respect to the RF coil axis, has been studied experimentally. The shift varies according to the light intensity and the orientation of the self-oscillator.