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Contents:
Topics- 10th IEC/TC90 (Superconductivity) International Conference Held in Kyoto
Feature Articles: Refrigeration and Cooling Technologies for Superconducting Equipment- Current Status and View of Refrigeration and Cooling Technologies for Superconducting
Systems- Development of 0.1W 4K Compact GM Refrigerating Machine- Development of 2W Compact Pulse Tube Refrigerating Machine- Development of 300W Large Stirling Type Pulse Tube Cryocooler- View of Slush Fluid Technology as a Refrigerant
Feature Article: Forum on Superconductivity Technology Trends 2006
Feature Articles: Trends of Superconductivity Diagnostic and Medical Technologies- Trends of High-Magnetic Field MRI Diagnostic System Technology- Current Status of SQUID Immune Test Technology- Global Trends of Magnetocardiograph- View of MT-DDS (Magnetic Target Drug Delivery System) Technology- View of Technology for Miniaturization of Charged Particle Therapy Equipment- Patent Information- Standardization Activities

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This work was subsidized by the Japan Keirin Association using
promotion funds from the KEIRIN RACE

http://keirin.jp

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10th IEC/TC90 (Superconductivity) International Conference Held in Kyoto
The 10th International Conference of IEC/TC90 (90th Technical Committee of International
Electrotechnical Commission - Superconductivity) was held from June 6 to 8, 2006, at the Centennial ClockTower Memorial Hall of Kyoto University attended by 47 representatives in total (1 person from the U. S. A.,
4 from Germany, 8 from China, 5 from Korea and 29 from Japan). Two new projects were approved andthe conference ended successfully.
The international conference of IEC/TC90 is held in Asia, Europe and the United States every 18
to 24 months on a rotation basis. The first conference was held in Tokyo in 1990 and the 10th conference
was held in Kyoto.
The conference consisted of an ad hoc group meeting (June 6 and 7), working group meeting(June 6 and 7), plenary session (June 8) and social event (June 7). The conference meetings and eventswere held in accordance with the IEC conference manual.
Chairman Dr. Loren F. Goodrich declared the opening of the conference at the plenary session
held on June 8. This was followed by a welcome speech and message of expectations for IEC/TC90
activities by Mr. Makoto Yokota, director, Standards Development and Planning Division, Industrial Scienceand Technology Policy and Environment Bureau, Ministry of Economy, Trade and Industry. An extensionof the term of office of the chairman from April 1, 2006, to March 31, 2009, was confirmed. The groups
briefed their activities and confirmed the deliberations made. Lastly, the venue for the 11th International
Conference of IEC/TC90 was deliberated. It was decided to select a venue later with a lapse of two years
after the current meeting on a rotation basis.

Mr. Makoto Yokota, Director, Standards
Development and Planning Division, Ministryof Economy, Trade and Industry, making thewelcome speech.

Dr. Loren F. Goodrich opening theconference.

The meeting in Kyoto deliberated the following topics.
1) Ad hoc Group 1 (Current leads)
Prof. Kozo Osamura, the rapporteur, reported the activities conducted since the Argonne
conference and future procedures.

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It was approved by agreement among four countries (Germany, China, Korea and Japan) that all kinds ofcurrent leads for power supply applied to superconducting equipment should be within the applicable scope,that it should be advanced to general requirements standardization which includes definition of related
terms and major characteristic test items and simultaneously with new work item proposal (NWIP), to move
up to formal procedures to establish a new WG. Ad hoc Group 1 would continue to function until a formal
WG is inaugurated.
2) Ad hoc Group 2 (uncertainty)
Dr. L. F. Goodrich, the rapporteur, reported the activities conducted since the Argonne conference
and future procedures. The term “uncertainty” was used at about 40% of the other TCs of IEC. The five
participant countries recognized that it was time for TC90 also to use it. However, it was also confirmedthat the application of “uncertainty” by TC90 would require the following considerations. (1) To try
beginning a stage (WG4) before WG5 (Nb-Ti wire room temperature pull test method and CDV stage)
which is currently being maintained and FDIS. (2) Related terms will quote GUM (Guide to the Expressionof Uncertainty in Measurement). Dr. L. F. Goodrich, the rapporteur, will present a specimen. (3) The
conveners were instructed to give sufficient consideration, such as describing in the remarks column amatch with “accuracy,” when producers and manufacturing organizations issue specifications to avoid
confusion in the transitory period. Ad hoc Group 2 will be disbanded when specimens of related terms andcaution items are developed in two or three months.
3) Maintenance of current IEC standards and future maintenance◊ A proposal was made on maintenance of WG1 (superconductivity glossary) and was approved. Prof.
Teruo Matsushita was recommended as a new convener and was approved.
◊ All WG2 (Nb-Ti wire Ic test method), WG7 (Nb3Sn wire Ic test method), WG8 (surface resistance test
method) and WG11 (Tc test method) are in the FDIS stage. It was approved to upgrade them to the IS
stage (Ed.2) in accordance with the standard schedule. The result of FDIS voting was approved for WG3(Bi wire Ic test method) and WG3 will move to IS. WG4 (Nb-Ti wire RRR test method) will move to the
FDIS stage in August and will incorporate “uncertainty.” Standards of WG2, WG3, WG7, WG8 and WG11
are already in the FDIS edited stage and have missed the opportunity of incorporating “uncertainty.” It was
confirmed that the incorporation of “uncertainty” will be taken up in Ed.3 and subsequent editions.
◊ A proposal was made tostart maintenance of WG4(Nb3Sn RRR test method)
and was approved.
◊ It was confirmed that
WG5 (Nb-Ti wire room
temperature tensile test
method)wouldbecirculated as a CDV draft
taking “uncertainty” into
consideration.
◊ Comment confirmation in
DC stage was confirmed
completed for WG9 (NbTiwire AC loss test method).
Plenary session
Moving of two standards to
the MCR issue stage wasapproved.

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4) Reporting on activities of countries and organizations◊ China reported that it was adopting a policy to enhance standardization and that superconductivity was
overviewed by SAC/TC265 chaired by Mr. Yang Qiaysheng (CAS). China reported that standardization
activities on superconductivity were undertaken in seven categories, namely, Jc, AC loss, levitational force,
RRR, Tc, glossary and so on.
◊ Germany reported that superconductivity standardization was taken up by GNC/K184 “Supraleiter”
chaired by Mr. Helmut Krauth and vice-chaired by Mr. Manfred Thoener. Germany reported maintenanceand other standardization activities classified into eleven IEC/WGs.
◊ Japan presented an overview of standardization activities. In addition to standardization of new
measurement methods and maintenance activities of existing international standards, Japan made interim
reports on product standardization activities related to superconducting generator conductors, SMES
(superconducting magnetic energy storage) conductors, superconducting current leads and othersuperconducting equipment. Japan also made an interim report on standardization activities insuperconducting electronics related to microwave and Josephson junction devices.
◊ Korea reported that KNC was established in 1995, to which experts are dispatched interfacing with 11
IEC/WGs. Korea reported on national projects (KSTAR, ITER and power application NFP) and on future
standardization (magnetization method Tc, surface resistance, current leads, irreversible magnetic field).
Prof. S. Y. Lee presented a draft for a surface resistance test method for superthin films and wasunanimously approved to move it to formal NWIP procedure.
◊ VAMAS
VAMAS made an interim report on basic standardization centering on test methods by four WGs.
A draft reflecting the results of RRT was presented on standardization of a room temperature tensile test
method of Nb3Sn wires.
5) Revised standardization strategy◊ The member countries were requested to review the 2004 Superconductivity Standardization Strategy
Paper SMB/2935/R.
◊ The member countries register their experts in WGs through IEC/Web. The participant countries wererequested to update their information. International Secretary Sato was requested to notify absent
P-member countries to update their information.
6) New work item proposal (NWIP)◊ It was approved that standardization ofgeneral requirements on definition andcharacteristic test methods of current leads
should be moved up to formal procedures
as a new work item proposal (NWIP) andto a proposal to establish a new WG
simultaneously.
◊ It was approved to move up
standardization of a surface resistance test
method for superthin films in WG8 (surface
Social event
resistance test method) to a formal NWIP.
(Yasuzo Tanaka, Director, Standardization Department, ISTEC)(Published in a Japanese version in the July 2006 issue of Superconductivity Web 21)
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Feature Articles:
Refrigeration and Cooling Technologies for Superconducting Equipment- Current Status and View of Refrigeration and Cooling Technologies forSuperconducting Systems Yasuharu Kamioka, Corporate Officer, Deputy General Manager
Development and Engineering Division
Taiyo Nippon Sanso Corporation
Recently, superconducting system is approaching commercialization and refrigeration andcooling technology tuned to be very important for the commercialization. Refrigeration device used insuperconducting system includes G-M, stirling, pulse tube cooler and turbine Brayton cycle refrigeration
machines. There are cryo-coolers that can be used in superconducting system to be commercialized.
However, many of them have been developed for cryo-pumps, MRI coolers, and experimental
equipments. The development of refrigeration machines that are satisfactory to superconducting
system is necessary not only in terms of shape, dimensions, but also cooling temperature, cooling
capacity, efficiency and other performance parameters.
The cooling capacity required for a high-temperature superconducting system is several watts toseveral kilo watts at from 40 to 70K. The efficiency of refrigeration machines decreases the lower thetemperature is and a larger refrigeration machine is needed for lower temperature even though the cooling
capacity is the same. Due to market constraints and regulation by the High Pressure Gas Control Law,
refrigeration machines of 1kW or higher at 70K are not sold in Japan. Refrigeration machines of 5 to 6kW
at 65K will be needed for large superconducting system and these refrigeration machines have not been
manufactured.
However, refrigeration machines of less than 1kW in cooling capacity at 70K have been
manufactured and these machines can be used in superconducting system relatively easily. A series ofmodifications and improvements will be needed to supply superconducting system to the general market.
On the other hand, refrigeration machines of 1kW or higher has constraints such as foregoing reason andthe capacities of G-M, stirling and pulse tube cooler (which are generally used as cooling machines of thisclass) cannot be increased for the technical reason. Because of this, refrigeration machines of other types
are needed to be developed. One candidate is the turbine Brayton cycle refrigeration machines. These
refrigeration machines larger than several ten kW in capacity have been manufactured for a cryogenic air
separation plant, a helium liquefaction plant and other uses. However, machines with a capacity of several
kW at about 70K have not been manufactured. Technology development for miniaturization is needed forcomponents such as turbines and heat exchangers.
Thus viewed, there are cooling machines of two regions, namely, G-M, stirling and pulse tube
cooling machines, whose operating principles are basically the same as those of small cooling machines ofless than 1kW in capacity, and turbine Brayton cycle cooling machines of more than 1kW in capacity.
Additionally, heat exchangers, subcooled liquid nitrogen circulating devices and other cooling devices that
thermally connect cooling machines and superconducting system will be important components in actual
system cooling.
A High-temperature superconducting system is entering a commercialization phase at present.
Before it can be widely accepted in society, the rapid development of refrigeration and cooling systems withdimensions, shape, temperature, performance, efficiency, reliability and high maintainability suitable forcommercialization is necessary.
(Published in a Japanese version in the June 2006 issue of Superconductivity Web 21)
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Feature Articles:
Refrigeration and Cooling Technologies for Superconducting Equipment- Development of 0.1W 4K Compact GM Refrigerating Machine Toru Maruyama
Engineering Department
Precision Equipment Division
Sumitomo Heavy Industries, Ltd.
1. Preface
As scientific equipment, medical apparatuses, semiconductor manufacturing systems andequipment and other systems become higher in precision and sensitivity, low temperature environments
often become essential as in cooling of samples and detectors. Rather than large equipment and systems,
compact refrigerating machines that can be handled easily are needed for equipment and systems forresearch and experimental purposes such as physical property measurement, for which universities andresearch organizations are principal customers. To meet these needs, Sumitomo Heavy Industries
developed a 0.1W 4KGM refrigerating machine.
2. Principal Specification of Compact 0.1W 4K GM Refrigerating MachineThis refrigerating machine has the smallest refrigeration capacity among the 4KGM refrigeratingmachines. However, it is compact, light and consumes minimum power. The machine not only attains
4K, but also is powered by single-phase 100V AC and is an energy saving, compact 4K refrigeratingmachine that can be plugged into an AC plug socket in laboratories and offices.
1) Refrigerating machine unit type: RDK-101D, compressor unit type: CNA-11B
2) Input power: AC 100V single phase
Power saving (50/60Hz): Steady state 1.2/1.3kW, maximum 1.3/1.5kW
3) Compact, lightweight: 7.2kg, 442 x 226 x 130mm (refrigerating machine unit)
4) Refrigeration capacity: Single stage 60K 3W, dual stages 0.1W or more at 4.2K
Minimum ultimate temperature: 2.5K
5) Can be installed in all directions
6) UL and CE compatible
The working fluid is a helium gas. The refrigerating machine consists of a helium compressor
unit, refrigerating machine unit, flexible hose and refrigerating machine power cable. The compressor unit
is air cooled for convenience in operating it. The machine is powered by AC 100V single phase and its
power consumption is low, equal to operating a dryer. It can be used easily like other measuring
instruments if caution is exercised regarding the electric power capacity on the primary side.
3. System Characteristics
The refrigeration capacity is the capacity to maintain the temperature below a specified
temperature when a thermal load is applied to the cooling stage of the refrigerating machine being operated.
The 4K refrigerating machines manufactured by Sumitomo Heavy Industries maintain a stable 4K-level
refrigeration capacity through the special construction of its cold storage unit and optimization of its cold
storage material. The first stage of the prototype failed to attain the specified refrigeration capacity (about
2W at 60K). However, the refrigeration capacity specification is accomplished by improving the cold

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storage material. Lowering of the refrigeration capacity when the refrigerating machine attitude is varied
one turn is kept low, 5% with Stage 1 and 15% with Stage 2, by employing a special construction with thesecond stage cold storage unit, allowing installation in all directions.
In electrical characteristics, the inrush current was 40A or less and maximum current duringcooling down, 15A or less, verifying that the machine can be connected to AC 100V single phase. Powerconsumption is 1.5kW maximum and is less than 1/5 that of a 1W 4KGM machine, attaining a 4K
temperature environment with low power consumption.

Refrigerating machine unit RDK-101D

Compressor unit CNA-11B(Published in a Japanese version in the June 2006 issue of Superconductivity Web 21)

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Feature Articles:
Refrigeration and Cooling Technologies for Superconducting Equipment- Development of 2W Compact Pulse Tube Refrigerating Machine Yukio Yasukawa
Equipment Technology Laboratory
Fuji Electric Advanced Technology Co., Ltd.
Compact pulse tube refrigerating machines are free of moving parts and feature low vibration andhigh reliability as expansion machines. They are attracting attention as a substitute for high-sensitivity
detectors that have been cooled by liquid nitrogen.
Fuji Electric Systems and Fuji Electric Advanced Technology have developed a compact
sterling-type pulse tube refrigerating machine with refrigeration output of a 2W class (Fig. 1). The machine
was developed incorporating “low vibration” and “high reliability” which were the features of the compact
sterling-type pulse tube refrigerating machine, aiming at achieving the compactness and ease of handling ofa sterling refrigerating machine. The expansion unit has a cooling unit at its end by connecting a cold
storage unit and pulse tube in “U” shape. A buffer tank, a component in the phase control mechanism, isintegrated with the compressor, achieving a monolithic construction as a refrigerating machine. Thisaffords ease of handling equal to that of a sterling refrigerating machine in mounting of material to be cooled
and in carrying and installing the refrigerating machine. The refrigeration capacity is 2.5 and 3.5W at
cooling-end temperature of 70 and 80K, respectively. (Power consumption 100W operation, 25°C
ambient temperature)
Vibration is not caused at the low-temperature end because no moving parts are installed.
However, it is important for the compressor to achieve low vibration equal to the level of vibration in coolingby liquid nitrogen. Fundamental vibration is canceled by installing opposite pistons in the compressor.
The flexure bearings supporting the pistons
have a higher linearity in piston operation byincreasing their radial rigidity. A reduced
imbalance of the unbalance force that is caused
by a constitutional unbalance between two
pistons has also contributed to attaining very
low vibration. The piston unit is fitted using an
automatic positioning device to build aclearance seal perfectly without any sliding.
Through these techniques, the vibration level at
the low temperature side can be confined to
1µm or less and on the fixed flange side, 0.1µm
or less. Continuous operation of 40,000 hours
at high reliability has been demonstrated.
One problem with the pulse tube
refrigerating machine is the low performance
100mm
caused by the installation direction. The
performancedifference
whenthe
low-temperature part is installed downward andFig. 1 2W compact pulse tube refrigerating machine
upward is 3% or less at 77K, which is

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considered entirely immune to problems in actual use. (Fig. 2) A separate refrigerating machine will be
put on the market in the future, built by separating the low temperature part from the compressor andconnecting it using a flexible connecting tube for use in manufacturing ultrahigh sensitivity detectors, withwhich impacts of electromagnetic noise caused by the compressor present a problem.
０°
+45°

-45°

-90°

+90°

18０°

5

Cooling Capacity（Ｗ）

4

Cold Head：70K(Input Power：100W)

Ambient Temp.
−10℃
＋10℃

3

＋25℃
2
1
0
-90

-45
0
45
Inclination of a piston axis （deg）

90

Fig. 2 Impact of cooling capacity by installation direction(Published in a Japanese version in the June 2006 issue of Superconductivity Web 21)

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Feature Articles:
Refrigeration and Cooling Technologies for Superconducting Equipment– Development of 300W Large Stirling Type Pulse Tube Cryocooler –Nobuo OkumuraGroup Manager
Vacuum and Cryogenic Group, Energy System Department
AISIN SEIKI CO., LTD.
A Stirling-type pulse tube cryocooler is being developed aiming at achieving a long lifetime andhigh efficiency. One of the characteristics of this cryocooler is an integrated configuration of a compressor
that has no wearing part and a pulse tube cold head that has no moving part. This cryocooler has nowearing part and few sources of gas pollution, inherently, affording far greater reliability than its same typepredecessor. Aisin Seiki has completed an endurance test of more than 50,000 hours using a compact
Stirling-type pulse tube cryocooler of model SPR-05, which has been sold since 1997 as a cryocooler used
for superconducting filters and radiation detectors.
The 300W large Stirling type pulse tube cryocooler now being developed is intended forincorporation in the Superconducting Magnetic Energy Storage System (SMES). This Cryocooler is mainlycomposed of three components, a compressor, pulse tube cold head and phase shifter. The compressor
uses clearance seal type piston supported by flexure bearings, and is expected long lifetime because of nowearing parts in it. The phase shifter with neck tubes realizes the system as the so-called third-generation
pulse tube cryocooler, and contributes to a high efficiency of this cryocooler.
One of the largest feature of this Stirling type pulse tube cryocooler is dual cylinder construction,
two regenerators and two pulse tubes with one cold head. This means as one compressor drives two
cryocoolers. This dual cylinder system is mainly designed for controlling less dispersions of gas flow in theregenerator and pulse tubes than usual construction of one cylinder. If one cylinder construction is adopted,
a regenerator and pulse tube become too thick to obtain the required PV work (expansion work), and thisconstruction induces gas flow disturbing and lowering of cryocooler
performance. This prevention of a dual cylinder construction make theStirling type pulse tube cryocooler fulfilled SMES system requirements.
This Stirling type cryocooler has accomplished cooling
performance of 300W at 77K with power consumption of 9kW.

Specification (March 2006)
Refrigeration capacity
300W at 77K
Power consumption

9kW or less (200V AC, 3 phases)

External dimensions mm

1200 width x 700 depth x 1600 height(Published in a Japanese version in the June 2006 issue of Superconductivity Web 21)

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Feature Articles:
Refrigeration and Cooling Technologies for Superconducting Equipment- View of Slush Fluid Technology as a Refrigerant Katsuhide Ohira
Professor
Institute of Fluid Science
Tohoku University“Slush” is a two-phase (solid-liquid) single-component cryogenic fluid containing solid particles(about 1mm in size) in liquid. Technology development of slush hydrogen and slush nitrogen is carried out
from practical aspects. 1) Slush hydrogen (temperature 14K) at solid mass ratio (solid fraction) of 50wt%
increases about 16% in density compared with liquid hydrogen (temperature 20K) and its cryogenic heat
capacity increases about 18% until it evaporates and becomes gas at 20K. Similarly, in the case of slush
nitrogen (temperature 63K), density increases about 16% and the cryogenic heat capacity increases about
22%. Utilizing these characteristics, if slush nitrogen is used as the refrigerant of a high-temperature
superconducting material, higher performance of wire can be expected compared with cooling by liquid
nitrogen (temperature 77K) and an advantage of an increase in heat capacity against penetration heat fromambient temperature, quenching and other generations of heat can be expected. The spreading ofpolymer electrolyte fuel cells (PEFCs) has already put into practical use the technology of transportinghydrogen as a fuel by lorries in the form of liquid hydrogen and storing it in car-borne tanks of fuel cellvehicles. When more fuel cells are installed and more superconducting equipment that uses metallic hightemperature superconducting materials (MgB2) is used, the use of slush hydrogen as a refrigerant ofsuperconducting power transmission, superconducting magnetic energy storage equipment and otherequipment can be expected if
slush hydrogen is used inplace of gaseous hydrogenand liquid hydrogen as a fuelof fuel cells.
When
Slush
hydrogen in the form of slushhydrogenＬＨ
２hydrogen is transported andstored using pipelines as
HydrogenSlush hydrogen producer
illustrated in Fig. 1, forliquefierPower transmission
example, superconducting Power transmission terminal
terminal
power transmission using
metallic high temperature
superconducting materials(MgB2) will also become
Fuel of fuel cells
Superconducting power
Liquid
燃料電池の燃料
feasible and the synergetic
residential)hydrogen (automotive,
超電導送電（ＭｇＢ
超伝導送電（ＭｇＢ
transmission (MgB2２)）（自動車用、家庭用）
Superconducting
effect of simultaneously
冷媒：スラッシュ水素
Refrigerant: Slush hydrogen
超電導電力貯蔵
超伝導電力貯蔵magnetic energy storagetransporting a fuel for fuel
(MgB
使用SMES）（MｇB22SMES)
cells and power can be
expected. In short-distanceFig. 1 Synergetic effect of combination of slush hydrogen andpower transportation, phasesuperconducting equipmentchange of slush hydrogen

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from solid-liquid to liquid-gas two-phase state by penetration heat or other heat to pipe can be prevented,
thereby mitigating undesirable phenomena for superconducting materials such as temperature oscillationsof refrigerant, even though this depends on the quantity to be transported.
When solid-liquid two phase fluids are transported by pipelines as illustrated in Fig. 1, normally,pressure losses during flowing inside the pipe increase and an increase in pump drive power comes into
question. A flow test of slush nitrogen in a pipe (15mm inner diameter) is currently conducted by theauthor and the pressure loss characteristics are obtained as shown in Fig. 2. The pressure loss coefficient(λ) decreases with an increase in Reynolds number (Re) and the pressure loss coefficient tends to become
equal (solid line) to or smaller than that of a liquid (dotted line) in a practical region (Re > 105). A similarreport has also been submitted on slush hydrogen, suggesting that hydrogen can be transported efficiently
and the cooling temperature of superconducting materials can also be lowered.
Compared with liquid helium, slush hydrogen has good characteristics as a refrigerant in the
aspects of required power for production and latent heat of evaporation, and expectations are placed on thedevelopment of commercialization technologies such as the acquisition of experimental data on physicalproperties and implementation of design techniques for equipment. More information on density meters,
mass flow meters and characteristics of nucleate pool boiling heat transfer is available in the referenced
literature. 1), 2)
0.1
77K-Liquid
63K-Liquid
Slush [7.5-12.5wt%]
Slush [12.5-17.5wt%]
Slush [17.5-22.5wt%]
Slush [22.5-27.5wt%]
Prandtl-Karman

0.08

λ

0.06

1

0.04

λ

= 2.0 log10 (Re λ ) − 0.8

0.02
0
4
1.00E+04
10

5

1.00E+05
10

Re
Re

6

1.00E+06
10

Fig. 2 Reynolds number (Re) and pressure loss coefficient (λ) when slush nitrogen flows in a pipe

References:
1) Katsuhide Ohira, J. Cryo. Soc. Jpn, Vol. 41 (2006), pp. 61-72. (in Japanese)
2) Katsuhide Ohira, Cryogenics, Vol. 44 (2004), pp. 59-68.

(Published in a Japanese version in the June 2006 issue of Superconductivity Web 21)
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Feature Article: Forum on Superconductivity Technology Trends 2006
On Monday, May 29, 2006, ISTEC held a forum on superconductivity technology trends titled“New Evolution of Applied Superconductivity Technology: Age of Competition - Superconductivity
Development at Turning Point” at the Toshi Center Hotel in Tokyo. Approximately 250 persons participatedincluding those from industry, academia, government, the press and general public. Results challenges andtrends in superconductivity technology development aiming at industrialization were reported and lively
discussions took place.
Yuuko Yasunaga, Director, Researchand Development Division, Industrial Science andTechnology Policy and Environment Bureau,
Ministry of Economy, Trade and Industry, andYukao Tanaka, Director, New Energy Technology
Development Department, New Energy andIndustrial Technology Development Organization(NEDO), delivered congratulatory messages.
Results of research and development reported at
the meeting gave the impression that thesuperconductivity
technology
wasfast
approaching commercialization. As one of the
key technologies in the 21st century, the direction
for the superconductivity technology in the
Shoji Tanaka, Director General, Superconductivity
medium to long range was discussed using a
Research Laboratory, delivering keynote lecture.
technology strategy map. New technologies
were expected to create new business ventures.
In a keynote lecture titled “Superconductivity Entering the Practical Phase in 2006, ” Shoji Tanaka,
Director General, Superconductivity Research Laboratory (SRL), stated that the superconductivity
technology has achieved great results overcoming various technical difficulties now that the technology wasentering its 20th anniversary after the discovery of high-temperature superconductivity. Tanaka indicatedthat a future image of the technology toward 2010 to 2020 was steadily unfolding thanks to thedevelopment of practical equipment and application to new spheres was more visible such as theenvironmental and medical fields in addition to energy saving and resource saving.
Koichi Nakao, Acting Director, Division of Material Science & Physics, SRL, reported on thedevelopment of a non-contact measuring method of long wires and cables and that measurement results
were fed back to wire development to expedite the development work.
Izumi Hirabayashi, Director, Bulk Superconductor Laboratory, SRL, reported on discovery of a
new material (Gd210) from analysis of a sample obtained in a space experiment. Hirabayashi introduced
application cases to various industries through the manufacture of large high performance bulk materials by
a new synthesis method using the new material, through significant improvement in the characteristics oftrapped magnetic fields thanks to recent technology development and through improved mechanicalstrength by impregnation of a resin.
Titled “NMR Application of Bulk Superconductor,” Takashi Nakamura, The Institute of Physicaland Chemical Research (RIKEN), reported the development of NMR equipment using bulk
superconductors. Nakamura stated that the technology could be applied to various fields for equipment
miniaturization through high magnetic fields of high-temperature superconducting bulk materials.

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Keiichi Tanabe, Director, Division of Electronic Devices, SRL, reported results of the projectfor development of superconducting network devices of a low power consumption type. The results
included verification of 120GHz clock operation by an SFQ 8-bit shift register using an advanced
process for nine Nb9 layers in LSI process development for low temperature device development andperfection of a design automation tool for logic synthesis in the development of basic circuit design
technology. In the development of high-temperature devices, recent results and future challenges
were reported including validation of high-speed operation by development of a new SFQ circuit layout(SBL method).
Titled “Application of Scanning Laser SQUID Microscope to LSI Inspection and Failure
Analysis,” Kiyoshi Nikawa, NEC Electronics Corporation, reported usefulness of a new scanninglaser SQUID microscope including success in identifying (inspecting) acceptable and non-acceptablechips from entire 256-DRAM wafers and identification of open circuits (failure analysis) in entire chips.
Yuh Shiohara, Director, Division of Superconducting Tapes and Wires, SRL, reported therecent status of high critical current density and long-wire process technology development as targetsof the applied and basic project. Activities in advanced R&D of application to equipment aimed atrefining wires were also reported.
Titled “Activities in Development of Transformer Using Bi and Y Wires,” Hidemi Hayashi,
Kyushu Electric Power Co., Inc., reported a large critical current of Y wires in a magnetic field, low AC
losses and development of element technologies of the transformer toward more practicaldevelopment at low cost.
Titled “High-temperature Superconducting Magnets in Test Run on Yamanashi Linear Motor
Train Experiment Line,” Motohiro Igarashi, Central Japan Railway Company, reported that applicationof high-temperature superconducting magnets based on basic technology for commercialization ofsuperconducting linear-motor trains established incorporating low-temperature superconducting
magnets developed in the past will enable conductor cooling without using a refrigerant. Igarashi
reported that this would simplify the construction and will enhance reliability of the linear-motor trainsystem and that the recent test run verified that high-temperature superconducting magnets could be
used in future linear-motor train systems.
Shigeo Nagaya, Chubu Electric Power Co., Inc. reported the development activities in Phase
II of the SMES Project of NEDO and on the current status and future challenges for real systeminterconnection tests to verify achievement of both economy and performance of the SMES systemtechnology based on the results obtained in the past development activities.
As a summary lecture, Osami Tsukamoto, Professor, Yokohama National University,
delivered a keynote lecture titled “Superconductivity Technology Contributing to Social Activities Superconductivity Technology Strategy Map.” Tsukamoto reported that recent results of thesuperconductivity technology showed that commercialization was feasible and that a medium and longrange direction could be visualized by drawing up an introductory scenario, technology map andtechnology roadmap having participated in the work to map out a superconductivity technology
strategy map sponsored by the Ministry of Economy, Trade and Industry and NEDO. Tsukamotoemphasized that the personnel concerned should be confident about the future of superconductivity.
The meeting reaffirmed the significance and importance of further activities by the industry,
academia and government for commercialization by moving in the direction shown in the
superconductivity technology strategy map after having taken the first step toward commercialization
based on the steady results achieved in R&D in various superconductivity segments.

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Lecture scene(Masaharu Saeki, Director, Research & Planning Department, ISTEC)(Published in a Japanese version in the July 2006 issue of Superconductivity Web 21)

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Feature Articles:
Trends of Superconductivity Diagnostic and Medical Technologies- Trends of High-Magnetic Field MRI Diagnostic System Technology Susumu Furuya
Chief Manager
Medical Community Relations Corporate Strategy Division
Hitachi Medical Corp.
Medium magnetic field superconducting systems ranging from 0.5 to 1.0T, which were theprincipal models in the MRI market of Japan, are being replaced by permanent magnet systems and themarket has been divided into two parts: these medium systems and high magnetic field systems higher
than 1.5T (See Fig. 1). In the future, 3.0T MRI systems for the whole body that have been approved under
the Pharmaceutical Affairs Law are expected to spread.
For high magnetic field MRI systems (Fig. 2), high function and high speed image pickup technologies
have been developed featuring a stable, high and uniform magnetic field and high S/N ratio by using
superconducting magnets and a reinforced gradient magnetic field power system. For high function image
pickup, research is underway on the imaging technology for the nerve system utilizing a high image resolution
and on so-called “molecular imaging” for bio function imaging aside from conventional form images. In
high-speed image pickup, the parallel imaging technology is spreading to shorten the image pickup time using
multiple receive coils that have different sensitivity distributions. High speed acquisition of 3D data of moving
organs such as the heart is also becoming feasible.

Year-on-year market share changes classified by magnetic field intensity segment
Number of systems per year

567
18

550

503

500
450

455

9

189

200

311

50
0

279

216
63
50

150
100

351

197

300
250

468

407

400
350

2

472

72

88
27
93

13
52
6
33

44

55

43

59

81

67

44

44

'00

'01

'02

'03

19 2
49

75

46

60

64

50

'04

'05

3T
1.5T
0.7〜1.0T
0.5T
0.4T
0.3T〜0.35T
0.2T
T or less

Source: Shin-iryoFig. 1 Shares of MRI systems in market in Japan by magnetic field intensity

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In MRI systems, a high magnetic field intensity increases the intensity of received MR signals andenhances the S/N ratio of images. This will be advantageous in picking up high definition and high speed
images. However, more caution is needed in operating super high magnetic field systems such as 3.0T
systems in terms of safety. The RF irradiation power used in signal excitation in particular increases
proportionally to the square of the magnetic field intensity and thus fast image picking up utilizing a highmagnetic field intensity is becoming difficult within safety standards. Therefore, the parallel imaging
technology mentioned above and the technology to control optimized irradiation waveforms are being
developed. R&D of superconducting magnets of 7T and 11T for whole body systems is also being
undertaken.
The tunnel type gantries are common for high magnetic field MRI systems because of the shapeof superconducting magnets. However, open-type MRI systems placing superconducting magnets
vertically in upper and lower positions are also manufactured in consideration of subjects (Fig. 3). MRI
systems are expected to become diverse in the future through technology development of superconducting
magnets such as high magnetic field systems, open systems and compact systems. Also the magnets
made in Japan are expected to reentry into the market. The technology will be applied to medical
treatment in the future such as drug delivery systems (DDS’s) using bulk magnets.

Fig. 2 Example of 1.5T superconducting
MRI system

Fig. 3 Open-type superconducting MRI system(Published in the Japanese version in the August 2006 issue of Superconductivity Web 21)

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Feature Articles:
Trends of Superconductivity Diagnostic and Medical Technologies- Current Status of SQUID Immune Test Technology Keiji Enpuku
Professor
Superconductivity System Science and Research Center
Graduate School of Information Science and Electrical Engineering
Kyushu University
Immune tests detect protein caused by various diseases using the coupling reaction of an antigen
and antibody and are frequently used in medical diagnoses such as blood tests. In recent years, theimportance of detecting various types of protein at a high speed and in high sensitivity is increasing and the
R&D of various high performance test systems is being undertaken. One such activity is SQUID(Superconducting QUantum Interference Device) immune test technology using magnetic markers and
SQUID magnetic sensors. In this test method, a test reagent (magnetic marker antibody) marked bymagnetic nanoparticles is coupled to the protein to be detected and the amount of protein is measured
based on a magnetic signal emitted by the magnetic marker. This test method assures a super highsensitivity that cannot be expected from the conventional optical technique and eliminates the so-called“washing” process, thereby affording fast tests. This method will allow fast detection of a very small
quantity of protein with high sensitivity.
For these reasons, R&D of SQUID immune test technology has been undertaken in various
countries and systematization research is conducted in Japan (Kyushu University, Toyohashi University ofTechnology, Advanced Research Laboratory, Hitachi Ltd. and others), the U. S. A. (UC Berkeley, Los
Alamos National Laboratory, Texas Center for Superconductivity, Magnesensor Inc. and others), Europe(PTB Berlin, Julich Laboratory, Braunschweig University, Chalmers University and others) and Taiwan(Taiwan National University). In system development, the aim is to make a test piece at room temperatureand SQUID cooled to a low temperature approach as near as possible (about 1mm). This is because themagnetic signal from the magnetic marker rapidly attenuates over the distance. A system of the SQUID
microscope type has been developed for this purpose.
Tests and experiments of various types of protein (IL6, IL8, IgE and others) using the SQUID test
technology are also being carried out. A detection sensitivity more than ten times compared with before is
exhibited, enabling detection of a trace amount on an atomic/molecular level. High-speed tests in theliquid phase eliminating the “washing” process are also being conducted. Usefulness compared with theconventional optical technique is being demonstrated. Nevertheless, the development of a magnetic
marker that shows a high dispersiveness without causing coagulation or sedimentation in a solution andthat emits a large magnetic signal that is optimum to this technique is an important objective in addition tohigh performance of systems to succeed in commercialization. Successful development of theseelements will ensure further enhancement in the SQUID test technology.

(Published in a Japanese version in the August 2006 issue of Superconductivity Web 21)

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Feature Articles:
Trends of Superconductivity Diagnostic and Medical Technologies- Global Trends of Magnetocardiograph Akihiko Kandori
Advanced Research Laboratory
Hitachi Ltd.

The magnetocardiograph features a very high sensitivity in detecting ischemia and is usefulfor detecting abnormal electrical excitation. For these reasons, the magnetocardiograph is attracting
attention as entirely new medical equipment. 1) The magnetocardiograph has started to be used by
medical organizations in Japan, the U. S. A., Germany, Finland, Italy, Taiwan, China, Korea and others
for research purposes. The number of papers on magnetocardiograms is increasing rapidly. Yearafter year, twice as many papers are published compared to the previous year. Papers onmagnetocardiograms are appearing in journals such as Circulation 2) and PACE 3) that are well known
as magazines specializing in heart diseases.
Against this backdrop, a satellite symposium “Global trends of magnetocardiograph” washeld on July 8, 2006, at the 23rd Annual Meeting of the Japanese Society of Electrocardiology as thefirst step toward standardization of magnetocardiograms. Presentations on the effectiveness ofmagnetocardiograms were made by Dr. Kirsten Tolstrup, Cedars-Sinai Medical Center, the U. S. A., Dr.
Chau-Chung Wu, National Taiwan University Hospital, Taiwan, Prof. Boyoung Joung, Yonsei
University College of Medicine, Korea, Prof. Shigeyuki Watanabe, University of Tsukuba, Japan, andProf. Satsuki Yamada, University of Tsukuba (currently at Mayo Clinic) and other purposes. The
presentation made by Dr. Tolstrup in particular was very interesting. Comparing scintigraphy under
exercised test (3-hour examination using radioisotope) and magnetocardiogram during a rest
(examination for about 10 minutes), Dr. Tolstrup reported that the sensitivities of ischemia detection
ratios of the two were almost equal. Dr. Tolstrup commented that magnetocardiographs were best
suited for screening examinations of patients with chest pains and that scintigraphy which ishazardous would be replaced by magnetocardiographs. The presentations made by the otherpresenters also reported that magnetocardiograms had a high ischemia detection ratio. Lastly, thesymposium agreed to cooperate in undertaking activities to standardize magnetocardiograms.
In Japan, a textbook on magnetocardiograms “Magnetocardiogram interpretation : A basic
manual,” authored and edited by Prof. Keiji Tsukada, Okayama University Graduate School, under thesupervision of Prof. Iwao Yamaguchi, director of Tsukuba University Hospital and councilor of
University of Tsukuba, in August by Corona Publishing Co., Ltd. 4) There are moves in Europe also
toward the standardization of magnetocardiograms. A workshop titled “European Taskforce of MCG”
is scheduled at BIOMAC ‘2006 in Vancouver, Canada, in August. Worldwide cooperation instandardization of magnetocardiographs will be undertaken in the future and magnetocardiographs
will be used as a more effective tool in clinical examinations.

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References
1) Yamada S et al., Internal Medicine 2005 Jan 44(1): 1-19
2) Wakai RT, et al., Circulation. 2003 Jan 21;107(2):307-12.
3) Kandori A, et al., Pacing Clin Electrophysiol. 2006 Jan;29(1):15-20.
4) http://www.coronasha.co.jp/np/detail.do?goods_id=2140(Published in a Japanese version in the August 2006 issue of Superconductivity Web 21)

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Feature Articles:
Trends of Superconductivity Diagnostic and Medical Technologies- View of MT-DDS (Magnetic Target Drug Delivery System) Technology Shigehiro Nishijima
Professor
Division of Sustainable Energy and Environmental Engineering
Graduate School of Engineering
Osaka University
Almost all medicines have side effects other than the originally intended efficacies. Side effects
are caused when medicines are used in excess of optimum concentrations, distributed in parts other thanthose intended or are used at a time when it is not necessary. In other words, the degree of side effects
can be mitigated significantly by controlling medicine distribution inside the body quantitatively, spatially andtimewise. Studies for optimization of medicine dosage examine the drug delivery system (DDS), which isconsidered in advanced medicine a key technology.
In DDS, endowing a character to a medicine to direct to a target is called “targeting.” A
substance that has an affinity with the target is used as a carrier and a drug as an object is delivered using
the in vivo behavior of the carrier. Methodologies to accomplish targeting include: (1) Local dose, (2)selective activation in a target area, (3) use of a medicine carrier and (4) control of in vivo behaviors from theoutside. As a technology to drastically enhance the targeting efficiency, “magnetic target DDS (MT-DDS),
which is one type of (4), has been attracting worldwide attention.
In MT-DDS, ferromagnetic (nano) particles are attached onto the drug and a magnetic field isimpressed to ferromagnetic particles to generate a magnetic force, by which a drug is guided. The drug isintroduced into the body by intravenous injection and is guided by placing a magnet outside the body. The
following three modes are considered for the MT-DDS system in practical use. 1) A system to prevent
dispersion of a drug by a magnetic force. 2) A system to trap and accumulate a drug in some part of ablood vessel. 3) A system to guide a drug in a desired direction to deliver it to an intended diseased part.
A development goal will be to implement System 3) in a deep part of the body when application to cancer
treatment is considered.
This concept has been proposed in the past, but development of technology to translate it into
reality has not been successful. One reason for this is that in human bodies, a drug cannot be madesufficiently voluminous so as to require a magnetic force. A large magnetic field and magnetic gradientcannot be formed several centimeters away from the magnet and there are requests that drug size should
be limited to about 200nm or less to avoid phagocytosis. These limits reduce the level of magnetic force.
These problems can be solved by generating a strong magnetic field and magnetic gradient in a deep partof the body. The goal will be to create a 5T/m magnetic field at 0.5T several centimeters inside the body.
Calculations and experiments have shown that this goal can be accomplished using a superconducting
magnet. Animal experiments have already been conducted and a consortium of the Medical,
Pharmaceutical and Engineering Departments and manufacturers of medical equipment is actively
undertaking R&D. This technology is expected to become key technology in advanced medicine in thenear future.

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Particle residence experiment with a rat applying a magnetic field. Ferromagnetic particles are
introduced into blood vessel of the rat and controllability of particles by the magnetic field has beenverified.

(Published in a Japanese version in the August 2006 issue of Superconductivity Web 21)

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Feature Articles:
Trends of Superconductivity Diagnostic and Medical Technologies- View of Technology for Miniaturization of Charged Particle Therapy
Equipment Satoru Yamada
Promotion of Carbon Therapy Section
Research Center for Charged Particle Therapy
National Institute of Radiological Sciences
Radiating protons, carbon and other ions into a substance, ions stop at a certain depth that isdetermined by ion energy. Large amount of the kinetic energy is transferred to the atoms of the substancein a narrow region immediately before the end points. This character of heavy charged particles produces
excellent results in heavy ion therapy.
The dose localization of heavy particle beams is far superior to X-rays and gamma-rays that havebeen used in conventional radiation therapy, suggesting possibilities for therapy with fewer side effects.
However, ions have to be accelerated to near the light velocity to use ions in deeply seated cancer
treatment, requiring a large accelerator such as a cyclotron and synchrotron. These large accelerators
cannot be housed in ordinary hospitals and special buildings to house them are needed. For example, afacility at the National Institute of Radiological Sciences can deliver silicone ions 30cm inside human bodies.
This facility requires a building of 65 x 120 m2, or the area of a soccer ground, to house it. As a result ofdevelopment research carried out by the Institute to make equipment more compact aimed at spreadingcarbon beam therapy, the equipment for carbon beam therapy can be reduced to a size housed in abuilding of about 50 x 60 m2. without any reduction in beam properties. Compared with carbon, protons
are far lighter and can be accelerated easily. Nevertheless, the equipment at the National Cancer Centerof Japan requires a building of about 40 x 60m2.
Miniaturization of accelerators using the superconducting technology has been studied.
Recently, two superconducting proton systems have been completed in Europe and test runs have beencommenced for the start of therapy. As far as the accelerator size is concerned, for example, a proton
synchrotron about 20m in circumference (average diameter 6.4m) can be made compact, to a cyclotron of
about 4m in outside diameter. One drawback with the superconducting cyclotron is that outgoing energy isfixed. For treatment of cancers, whose depths vary from one patient to another, proton energy is reducedby passing it through a carbon plate or other material. This process results in a wide spread in energy andprotons with energy widths below a predetermined value must be selected with an analizer magnet. This
greatly reduces the proton intensity and generates unwanted activation. Furthermore, a beam transportsystem, beam shaping equipment and other equipment occupy a far larger space than the accelerator itself
and the medical side is making a variety of requests including rapid switching of the magnetic field (about 1
minute) for this part. Application of superconductivity to heavy ion therapy is yet to start.

(Published in a Japanese version in the August 2006 issue of Superconductivity Web 21)

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Patent Information
Introduction of Published Unexamined Patents in the 1st Quarter of Fiscal 2006
The following are ISTEC’s patents published from April through June, 2006. For more information,access the homepage of the Patent Office of Japan and visit the Industrial Property Digital Library (IPDL).
1) Publication No. 2006-101585 “Superconducting Bearing and Magnetic Levitation System”
This invention relates to superconducting members in a magnetic bearing and a superconducting
transfer vehicle, in which the pinning forces of the superconductors are utilized for levitation by facing thesuperconducting members to permanent magnetic members. Such superconducting members join pluralsuperconductors to obtain a large area of the facing surface. However, the trapped magnetic field
decreases near the junctions, causing a non- uniformity of the magnetic field and becoming a major factor
for generation of electric losses. This invention is applied a construction that stacks the superconductor
layers that join plural superconductors, and characterized that the superconductors of each layer areformed in a chevron form and junctions of superconductors of one layer are located in apexes of chevronsof other layer. The superconducting members of this invention excel in trapped magnetic field characteristics.
Junction

Junction

Magnetic
flux density

Magnetic
flux density

Example of conventional
construction

This invention

2) Publication No. 2006-117986 “Measuring and Evaluation Method for a Plume, Laser Ablation
Method and Laser Ablation System”
This invention relates to plume measuring and evaluation methods, laser ablation method and laser
ablation system. The purpose of this invention is to deposit a laser ablation thin film that has a good
crystalline property or stable electric characteristics with a good reproducibility. One of the causes for
non-uniform or unstable thin film characteristics in the laser ablation method is instability of laser oscillation.
This invention is featured by acquirement of light intensity data of plume, generated when a laser beam isradiated onto the evaporation source target, using an area image sensor and estimation of the plume shape inreal time using the foregoing measurement results. This enables control of laser oscillation intensity
according to the change of the plume shape. A plume with a stable shape can be maintained for a long time.
This invention is especially effective in the film deposition process of high-temperature oxide superconducting
devices that require high quality thin films.
(Katsuo Nakazato, Director, Research and Development Promotion Division, SRL/ISTEC)(Published in a Japanese version in the August 2006 issue of Superconductivity Web 21)
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Standardization Activities
Topics in June
- IEC-APC Honors Professor Shintomi and Murase and Other Persons forContribution to IEC International Standardization At its General Assembly of 16th IEC Activity Promotion Committee held on Wednesday, May 10,
2006, the IEC Activity Promotion Committee (IEC-APC) honored Prof. Takakazu Shintomi of Nihon
University, Prof. Satoru Murase of Okayama University and 11 other persons for a major contribution madeto IEC international standardization by conferring IEC-APC chairperson awards.
The IEC-APC chairperson awards are awarded each year to individuals or groups making aprominent contribution in the IEC segment such as development of IEC standards proposed by Japan.
The awards are presented by IEC-APC that was inaugurated in 1991 for contribution to IEC (International
Electrotechnical Commission) and for reflection of the views of the industry.
In 2006, one person received the special award, 11 persons received chairperson awards, andeight persons received letters of appreciation.
The IEC-APC chairperson award was awarded to Prof. Takakazu Shintomi of Nihon University(Graduate School) for his great contribution to standardization in Japan and in the world for IEC-APC
through his activities at WG6 of IEC/TC90 (Superconductivity) since 1995 in promoting international
standardization of IEC/TC90 and for his service as a WG6 convener.
The IEC-APC chairperson award was awarded to Prof. Satoru Murase of the National University
Corporation, Okayama University (Graduate School) for his great contribution to standardization in Japanand in the world for promotion of superconductivity standardization since 1990 when Japan accepted therole as an international secretariat and for his service as a WG11 convener.

Commemorative photograph of award recipients (Prof. Satoru Murase on right of back row)

(Published in a Japanese version in the June 2006 issue of Superconductivity Web 21)

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Topics in August- NEDO Awards Research Contract for “Standardization of Technical Infrastructure forSuperconducting Power Devices and Systems” to ISTEC -On May 11, 2006, the Independent Administrative Agency, New Energy and Industrial
Technology Development Organization (NEDO) awarded a research contract to the International
Superconductivity Technology Center (ISTEC), a foundation on standardization of technical infrastructure
for superconducting power devices and systems.
The contract is outlined in the following.
Purposes
As part of the standardization of technical infrastructure for superconducting power devices andsystems, the contract calls for a study of technologies related to product standardization of superconducting
magnetic energy storage systems (SMES, flywheels), superconducting power cables, superconducting
current limiters, superconducting transformers and other equipment for use in mapping out and developing
draft international standards documents. Studies under this project shall be undertaken in conjunction
with: (1) Ongoing project “Superconducting Power Network Control Technology Development” undertaken
between 2004 and 2007 and (2) Ongoing project “Research and Development of Superconductivity
Applied Basic Technology” undertaken between 2003 and 2007.
Study Themes
Studies shall be undertaken on the following themes.
(1) Study of current lead characteristics
To reflect the results of technical studies of characteristic test methods of current leads that are
essential to superconducting power devices such as superconducting power cables, superconducting
current limiters, superconducting transformers, SMES and superconducting rotating machines on draft
standards. To develop new work item proposals (NWIPs) targeting at completion in 2006 for contribution
to IEC international standardization.
(2) Study of characteristics of long wires
To study test technologies and test methods centering on a critical current (Ic) test method andmechanical characteristic test methods for long Nb-Ti, Nb3Sn and other low-temperature superconducting
wires and long-Bi, Y and other high-temperature superconducting wires. To develop draft standards
based on them and to seek an international consensus aimed at proposing them as international standards
at meetings with international experts.
(3) Study of technologies for SMES and other superconducting power devices
To determine objects for standardization of superconducting power devices based on results ofstudies in the study contract on technical infrastructure of superconducting power devices gained up to
March 2006 including superconducting power cables, superconducting current limiters, superconducting
transformers, SMES and superconducting rotating machines.

Fall, 2006

© ISTEC 2006 All rights reserved.

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Fall, 2006

Date of Issue: October 16, 2006

Superconductivity Web21
Superconductivity

Published by International Superconductivity Technology Center
5-34-3, Shimbashi, Minato-ku, Tokyo 105-0004, Japan
Tel: +81-3-3431-4002, Fax: +81-3-3431-4044

Study Period
April 2006 to March 2009
Study Organization
To be studied by Technical Study Committee chaired by Prof. Kozo Osamura (Research Institutefor Applied Sciences), by SMES Subcommittee chaired by Prof. Takakazu Shintomi (Nihon University), by
Current Lead Subcommittee chaired by Prof. Takakazu Shintomi, and by Long Wire Characteristic
Subcommittee chaired by Dr. Koichi Nakao (ISTEC/SRL).

(Published in a Japanese version in the August 2006 issue of Superconductivity Web 21)(Yasuzo Tanaka, Director, Standardization Department, ISTEC)

Top of Superconductivity Web21

Fall, 2006

© ISTEC 2006 All rights reserved.

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