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Double pancake test coils are fabricated in order to examine the mechanical properties of Bi-2223 conductors under high hoop stress. The critical current of the high-[I.sub.c] test coil is shown to be 164 A, where the hoop stress is estimated at 323 MPa and the high-strength test coil has burst at a hoop stress of approximately 200 MPa.

The critical current and index value of Bi-2223/Ag superconductor is evaluated in high magnetic field. The Bi-2223/Ag conductor has reached enough potential to realize high field applications over 1 GHz NMR spectrometer.

The magnetic force enhancement by using a high temperature superconducting (HTS) bulk cylinder with a G-M cryocooler is discussed. Results suggest the enhancement of the magnetic force with the HTS bulk cylinder due to the generation of force field magnitude of 564 [T.sup.2]/m at 12 T for back up magnet.

The development of a workbench magnet generating magnetic fields on a room-temperature (RT) plate is discussed. Findings reveal the successful generation of magnetic fields of over 3 T at the center of the RT plate

A new fabrication process for the manufacture of various [Nb.sub.3]Sn conductors and filaments by employing the diffusion reaction between Nb and Ag-Sn alloys is being described. The results show that the superconductivity of the conductors linearly increases with the Sn content in the alloy.

A variable-field-direction superconducting magnet that can change its field direction continuously in a two-dimensional plane is developed. A cryo-stat with two types of room-temperature bores is constructed and a cooling test without solenoid coils and supporting structures is conducted.

New applications of bulk high-temperature superconductors such as BSCCO or YBCO in high magnetic fields is proposed. The results show that the magnetic flux concentration was observed even in the high magnetic field over 20 T.

The first 920 MHz high-resolution Nuclear Magnetic Resonance (NMR) magnets are installed at the Tsukuba Magnet Laboratory of the National Institute for Material Science. The signal-to-nose ratio of 0.1 percent ethylbenzene using a proton-selective probe is high as 2981.

New applications of bulk high-temperature superconductors (HTS) in high magnetic fields are described and discussed.

Noise reduction in high-field resistive magnets is achieved by means of shielding with a YBCO cylinder.

Operation of a 920-MHz high-resolution nuclear magnetic resonance (NMR) magnet at Tsukuba Magnet Laboratory (TML) is described and discussed.

Design of a superconducting magnet comprised of Nb[subscript 3]Sn and NbTi conductors is described. The magnet is meant to generate spatially uniform magnetic force fields up to 860 T[superscript 2]/m.

Research involving a high-field nuclear magnetic resonance (NMR) magnet is reported. The work was accomplished at the Tsukuba Magnet Laboratory at the National Institute for Materials ScienceTsukuba, Ibaraki, Japan.

Results involving switching behaviors of the persistent-current switch (PCS), and of field-decay behaviors in long-term operations, are reported. Compensation of magnetic fields, using a NbTi cylinder, is also discussed.

Representative studies involving superconducting inserts in high-field solenoids are presented and discussed.

Superconducting magnets were design for uniform and high magnetic force field generation.

The development of a 1 GHz superconducting NMR magnet at the Tsukuba Magnet Laboratory of the National Research Institute for Metals, is described.

Superconducting magnets for producing uniform magnetic force fields have been designed. The magnets generate a uniform force field of 240 T squared per meter in a cylindrical space of 10 mm in diameter and 10 mm in height. The magnetic force field fluctuation along the z-direction is better than 0.4%. It is made up of NbTi conductors and was able to achieve the design current in liquid helium. The magnet will be installed in its own cryostat cooled with a G-M refrigerator.

The results of engineering design and R&D studies conducted on candidate superconductors for the inner coil of the 1 GHz superconducting nuclear magnetic resonance (NMR) magnet at the Tsukuba Magnet Laboratory of the National Research Institute for Metals in Japan is presented. The engineering design of the high resolution NMR magnet, which requires high levels of field homogeneity and field stability, has been completed and the production of the superconductors has began.

Progress on the development of the Bi-2212/Ag insert magnets is presented. The coils were constructed via a wind and react process using silver sheathed Bi-2212 multifilamentary tapes. The Bi-2212/Ag 54 filament tapes were fabricated using a powder-in-tube approach. Results indicate that understanding the bubbling phenomena is essential to further improvement of the transport properties of the Bi-2212/Ag magnet.

A round-shaped Bi-22212/Ag wire with tape-shaped multifilaments was developed including 126-960 tape-shaped filaments having a triple rotation symmetry and a good crystal alignment in every filament. The wire was referred to the Rotation-Symmetric Arranged Tape-in-tube wire (ROSATwire) because the ROSATwire structure produces complete symmetrical arrangement of the tape-shaped filaments and allows the use of an extrusion machine. The fabrication process is also found to be cost-effective.

A study was conducted on the current decay in four closed high temperature superconducting (HTS) coil circuits. The coil consists of a single conductor, persistent current switch and their joints. Tests reveal that the HTS persistent current switches functioned properly. A Hall probe was employed in monitoring the magnetic field of the HTS coil for current decay measurements.

Construction of the 40 T class hybrid magnet system was completed at NRIM. The hybrid magnet will be able to generates the world's highest continuous magnetic field of 40 T class in a 30 mm clear bore. Generation of high magnetic field with the hybrid magnet causes serious problems due to large electromagnetic force. To handle the problems, we have developed new type [(Nb,Ti).sub.3]Sn conductors, new coil clamp technique for 15 T class superconducting magnet, new copper alloy for 25T class polihelix-type water-cooled magnet and new manufacturing procedure which includes winding and machining process for water-cooled magnets through its research and development.

The construction of the 40 T class hybrid magnet system was completed at the Tsukuba Magnet Laboratory of NRIM. Now, the total system test is being performed. This system consists of a hybrid magnet composed of a water cooled magnet and a superconducting magnet, power supplies for these magnets, water cooling system, and control system. The power supply for the water cooled magnet is a low ripple power supply, and it also has a 'soft stop circuit' to prevent quenching of the superconducting magnet. In order to confirm the achievement of low current ripple and efficiency of the soft stop circuit, we carefully analyzed the behavior of this circuit. As a results, we confirmed that the performance of the power supply satisfies the specifications. Also, we verified efficiency of the soft stop circuit.

Two pancake coils wound from Bi2Sr2CaCuOx(Bi-2212)/Ag tape fabricated by the dip-coating and melt-solidification process are reported. The first, which is designed for use as an insert in a superconducting magnet, generates a magnetic field of 21.8 T in the full superconducting state. The second, which is designed for operation at 20 K, generates 1.53 T at 20 K in helium gas.

An automated control and monitoring system is developed for a 920 MHz NMR magnet that is installed at Tsukuba Magnet Laboratory (TML) in April 2002. The cryostat is equipped with an automated control and monitoring system in order to achieve a quick energization and long-term operation with a minimum number of operators.

A magnetic force booster device is developed to enhance magnetic force fields generated by superconducting magnets. The results show that the magnetic force booster could enhance the magnetic force fields generated by the commercial superconducting magnet to higher than 1360 T(super 2)/ m.

The design of a superconducting magnet that can change its field direction continuously in a 2-D plane is described and discussed.

A development plan for 1 GHz-class nuclear magnetic resonance (NMR) magnets, being implemented at the Tsukuba Magnet Laboratory, Tsukuba, Japan, is discussed. A related NMR facility, based on the Japanese genome science plan, is introduced.

In order to minimize the quantity of superconducting (s.c.) wire used in s.c. High Gradient Magnetic Separation (HGMS) systems, we developed two computational techniques to simulate the magnetic field created by s.c. solenoils: a detailed numerical model, and a simplified graphical method. We used the numerical model as a standard of comparison to evaluate the accuracy of the graphical method. The evaluated error in the graphical determination of s.c. wire volume was less than 4.6% in hypothetical HGMS systems for purifying dissolved fission products in nuclear reprocessing. Comparing with the case where an HGMS filter and an s.c. solenoid have the same length, our optimization technique shows that a large amount of wire reduction is possible.