著者

相山 義道 梅田 政一

出版者

公益社団法人 低温工学・超電導学会 (旧 社団法人 低温工学協会)

雑誌

低温工学 (ISSN:03892441)

巻号頁・発行日

vol.36, no.9, pp.516-524, 2001

被引用文献数

1

---

The historic story of the superconducting (SC) magnet for MHD ETL Mark V Facility (cf. Fig. 1) is presented. This SC magnet was developed in the MHD Project (1966-75), which was one of the first MITI/AIST Large-Scale R & D Projects and the first national project for superconductor applications in Japan. This SC magnet had been the largest in Japan through 1982 when the Japanese LCT coil was made by JAERI. It was completed in 1973 after many difficulties, some fatal and some trivial, because of a lack of knowledge, before it could generate maximum magnetic field 7T with stored energy 65MJ. Because technological problems had piled up and because no management know-how of national projects on technology development had been accumulated before then in the forefront of worldwide technological advances, “step by step” advances and “trial and error” attempts in the progress of the project had to be done over again. The paper is divided into three parts. Part I describes the process of determining the specifications of the magnet and the conductor tests before the magnet was manufactured.

著者

力石 浩孝

出版者

公益社団法人 低温工学・超電導学会 (旧 社団法人 低温工学協会)

雑誌

低温工学 (ISSN:03892441)

巻号頁・発行日

vol.53, no.3, pp.122-129, 2018-05-20 (Released:2018-07-14)

参考文献数

6

---

The Large Helical Device (LHD) is a fusion plasma experimental device operating at the National Institute for Fusion Science. The LHD uses superconducting coils to generate a magnetic field for plasma confinement, and each coil is excited by a large-scale DC power supply. This paper introduces the DC power system and its design concept.

著者

冨中 利治

出版者

公益社団法人 低温工学・超電導学会 (旧 社団法人 低温工学協会)

雑誌

低温工学 (ISSN:03892441)

巻号頁・発行日

vol.49, no.4, pp.192-201, 2014-04-25 (Released:2014-05-20)

参考文献数

19

被引用文献数

1 1

---

The analytical formulae of the magnetic field, the vector potential and the inductances of long helical conductors with an arbitrary pitch are given as a unified scheme from a helical solenoid to a straight conductor. It is also shown that the obtained expressions are consistent with the well-known expressions for a closely wound helical solenoid and a straight conductor in both limits of the infinitesimal and infinite twist pitches, respectively. In addition, the right-handed and left-handed long helical conductors are clearly treated for this unified scheme.

著者

秋山 庸子 野村 直希 三島 史人 西嶋 茂宏

出版者

公益社団法人 低温工学・超電導学会 (旧 社団法人 低温工学協会)

雑誌

低温工学 (ISSN:03892441)

巻号頁・発行日

vol.55, no.3, pp.172-178, 2020-05-20 (Released:2020-06-04)

参考文献数

16

被引用文献数

3

---

An investigation as to whether or not superconducting high-gradient magnetic separation is capable of reducing the volume of cesium in contaminated soil is reviewed. This unique physical method can selectively remove paramagnetic 2:1-type clay minerals that strongly trap cesium inside the interlaminar site from soil suspensions. However, there are technical issues, such as wide particle size distribution and particle aggregation. To solve these problems, advanced pretreatments of advanced classification and alkaline dispersion treatments were performed, and the radioactivity concentration reduction rate was successfully increased. Based on the results, issues for practical application were discussed.

著者

中川 久司

出版者

公益社団法人 低温工学・超電導学会 (旧 社団法人 低温工学協会)

雑誌

低温工学 (ISSN:03892441)

巻号頁・発行日

vol.50, no.6, pp.298-305, 2015-06-25 (Released:2015-07-07)

参考文献数

24

被引用文献数

1

---

In order to ensure the reliability of research results obtained in very low temperature fields, it is important that very low temperature measurement is traceable to the internationally agreed the Provisional Low Temperature Scale of 2000 (PLTS 2000). The PLTS-2000 is defined by the relationship of 3He melting pressure pm to temperature T2000 in the range of 0.9 mK to 1 K and provides four intrinsic fixed points on the melting curve. In order to realize the PLTS-2000, it is necessary to cool 3He at melting pressure down to the possible lowest temperature using a nuclear demagnetization cryostat. This cryostat must be capable of working reliably and continuously over long periods of time during ultra-low temperature experiments. In this article, we give information about low-temperature techniques for realizing the PLTS-2000 based on our experiences of designing and constructing in-house ultra-low temperature apparatus.

著者

山田 穣

出版者

公益社団法人 低温工学・超電導学会 (旧 社団法人 低温工学協会)

雑誌

低温工学 (ISSN:03892441)

巻号頁・発行日

vol.54, no.1, pp.37-42, 2019-01-20 (Released:2019-02-11)

参考文献数

7

著者

門奈 五兵

出版者

公益社団法人 低温工学・超電導学会 (旧 社団法人 低温工学協会)

雑誌

低温工学 (ISSN:03892441)

巻号頁・発行日

vol.8, no.3, pp.118-119, 1973

著者

山本 明保 Jeremy WEISS Mark AINSLIE Anatolii POLYANSKII David LARBALESTIER Eric HELLSTROM

出版者

公益社団法人 低温工学・超電導学会 (旧 社団法人 低温工学協会)

雑誌

低温工学 (ISSN:03892441)

巻号頁・発行日

vol.52, no.6, pp.397-404, 2017-11-20 (Released:2017-12-08)

参考文献数

47

---

This article reviews the recent development of bulk trapped field magnet made with iron-based superconductor (IBSC). A trapped field of over 1 T at 5 K and 0.5 T at 20 K has been measured between a stack of magnetized cylinders of bulk polycrystalline Ba0.6K0.4Fe2As2 superconductors 10 mm in diameter. Magneto-optical imaging revealed a trapped field distribution corresponding to uniform macroscopic current loops circulating through the sample. A standard numerical modelling technique using the measured Jc(B, T) characteristics of a small specimen reproduced the experimentally measured trapped fields well, again indicating the homogeneous current loops in the polycrystalline bulk. Given the untextured polycrystalline nature of the cylinders and their large irreversibility field, it is expected that larger IBSC bulks could trap much higher field.

著者

松下 照男 船木 和夫

出版者

公益社団法人 低温工学・超電導学会 (旧 社団法人 低温工学協会)

雑誌

低温工学 (ISSN:03892441)

巻号頁・発行日

vol.39, no.1, pp.2-9, 2004 (Released:2007-02-16)

参考文献数

10

---

This article focuses on Poynting’s vector which is defined by a vector product of electric and magnetic fields and plays an important role in considering a flow of electromagnetic energy between power supplies and various types of electromagnetic devices in electrical, electronical and information networks. Poynting’s vector is introduced from a law of energy conservation and its surface integral on an arbitrary domain is equal to the electromagnetic power inside it. This relation can be applied to any system in which there is an interest in the energy flow. Validity of the speculation that Poynting’s vector directly gives the energy flow is examined in various cases. It is pointed out that Poynting’s vector is not equal to the energy flow in some cases. Also discussed is the condition under which the equality holds.

著者

小林 慎一 中島 隆芳 山崎 浩平 佐藤 謙一

出版者

公益社団法人 低温工学・超電導学会 (旧 社団法人 低温工学協会)

雑誌

低温工学 (ISSN:03892441)

巻号頁・発行日

vol.47, no.7, pp.422-429, 2012-07-25 (Released:2012-09-12)

参考文献数

27

被引用文献数

2 2

---

Since the discovery of bismuth-based high-temperature superconductors in 1988 in Japan, much work has been done to develop superconducting wires and their applications. Applications include cables, motors, transformers and fault current limiters used at 77.3 K, high field magnets and motors used at 20 K and super-high field magnets and current leads used at 4.2 K. Some applications are already commercial products. This paper introduces the wire fabrication methods, wire characteristics and application apparatus.

著者

大平 勝秀

出版者

公益社団法人 低温工学・超電導学会 (旧 社団法人 低温工学協会)

雑誌

低温工学 (ISSN:03892441)

巻号頁・発行日

vol.41, no.2, pp.61-72, 2006 (Released:2007-02-15)

参考文献数

29

被引用文献数

6 6

---

Since liquid hydrogen has a high specific impulse as fuel for rockets, its technology has been developed in connection with space technology programs. On the other hand, with the recent advance of technologies such as fuel-cell vehicles and stationary fuel-cell systems, liquid hydrogen is also expected to be used as an efficient means of transporting and storing hydrogen used as a source for clean energy. Slush hydrogen is a two-phase solid-liquid cryogenic fluid consisting of solid hydrogen particles in liquid hydrogen. Compared with liquid hydrogen, the density and cryogenic heat capacity of slush hydrogen with a solid fraction of 50% increase by 16% and 18%, respectively. Various applications of slush hydrogen are anticipated such as fuel for reusable space shuttles and fuel cells, and as a more efficient means of transporting and storing liquid hydrogen. This paper describes the applications and technology developments of liquid and slush hydrogen.

著者

春山 富義 吉崎 亮造

出版者

公益社団法人 低温工学・超電導学会 (旧 社団法人 低温工学協会)

雑誌

低温工学 (ISSN:03892441)

巻号頁・発行日

vol.17, no.3, pp.179-180, 1982-06-25 (Released:2010-02-26)

参考文献数

2

著者

川島 健司 伊豫 彰 荻野 拓

出版者

公益社団法人 低温工学・超電導学会 (旧 社団法人 低温工学協会)

雑誌

低温工学 (ISSN:03892441)

巻号頁・発行日

vol.52, no.6, pp.389-396, 2017-11-20 (Released:2017-12-08)

参考文献数

46

---

We report discoveries and properties of new 112-type (Ca,Ln)FeAs2 (Ln = La ~ Gd) and 1144-type AeAFe4As4(Ae = Ca, Sr, Ba, Eu, A = K, Rb, Cs) Fe-based superconductor structures. (Ca,Ln)FeAs2 has a monoclinic system with a space group P21/m composed of two Ca(Pr) planes, Fe2As2 layers, and As2 zigzag chain layers. (Ca,Ln)FeAs2 shows superconductivity with a transition temperature (Tc) at 20 ~ 40 K. Although (Ca,Ln)FeAs2 has thick blocking layers, it has relatively high critical current density over 106 A/cm2 at 5 K (self-field). AeAFe4As4 has a tetragonal system with a space group, P4/mmm, Ae and A layers are inserted alternately between the Fe2As2 layers in the c-axis direction. AeAFe4As4 is a stoichiometric compound having Tc = 31 ~ 36 K, depending only on the combination of Ae and A. Both new superconductors are promising materials for application due to their characteristic properties.

著者

田中 雅光 藤巻 朗 井上 弘士

出版者

公益社団法人 低温工学・超電導学会 (旧 社団法人 低温工学協会)

雑誌

低温工学 (ISSN:03892441)

巻号頁・発行日

vol.52, no.5, pp.323-331, 2017-09-20 (Released:2017-10-27)

参考文献数

50

---

The recent trend and perspectives for high-performance microprocessors based on superconductor single-fluxquantum (SFQ) logic families are described. The rapid single-flux-quantum (RSFQ) and its energy-efficient derivatives are promising as a next-generation digital circuit technology for very-large-scale integration in the post-Moore's era because of the capability of ultrahigh-frequency operation over 100 GHz and low energy consumption. Several ongoing research projects as well as results reported, including several demonstrations of SFQ-based microprocessors and their components, are reviewed.

著者

池田 博 土井 浩一郎 福田 洋一 野口 隆志 中嶋 俊哉 飯村 憲 渋谷 和雄

出版者

公益社団法人 低温工学・超電導学会 (旧 社団法人 低温工学協会)

雑誌

低温工学 (ISSN:03892441)

巻号頁・発行日

vol.39, no.8, pp.348-353, 2004 (Released:2008-03-10)

参考文献数

8

被引用文献数

3 3

---

From February 2003 to January 2004, a new superconducting gravimeter with a cryocooler was installed to replace the former device at the Syowa station in Antarctica. The new gravimeter has a high sensitivity of one nano-gal and is being used to survey the earth's core in the Global Geodynamics Project. A new type of diaphragm was confirmed to well isolate the vibration from the refrigerator cold-head and effectively prevent solid air contamination. A remote monitoring system from Japan is also going to be installed.

著者

門奈 五兵

出版者

公益社団法人 低温工学・超電導学会 (旧 社団法人 低温工学協会)

雑誌

低温工学 (ISSN:03892441)

巻号頁・発行日

vol.8, no.3, pp.118-119, 1973-07-15 (Released:2010-02-26)

著者

東川 甲平 井上 昌睦 木須 隆暢

出版者

公益社団法人 低温工学・超電導学会 (旧 社団法人 低温工学協会)

雑誌

低温工学 (ISSN:03892441)

巻号頁・発行日

vol.49, no.9, pp.485-493, 2014-09-25 (Released:2014-10-24)

参考文献数

15

---

This article reviews a method for characterizing the local critical current density (Jc) distribution in superconducting tapes and wires based on scanning Hall-probe microscopy (SHPM). This method is very powerful for (1) finding the bottleneck that limits the global performance of a superconductor, (2) investigating the local inhomogeneity that may become the origin of local quench, especially in HTS applications, (3) establishing the processes for narrow and/or multifilamentary HTS conductors for reducing the magnetization in magnet applications and the AC losses in power applications. The principle and the functions of this technique are introduced by referring to characterization examples of REBCO coated conductors and an MgB2 wire.

著者

田辺 圭一

出版者

公益社団法人 低温工学・超電導学会 (旧 社団法人 低温工学協会)

雑誌

低温工学 (ISSN:03892441)

巻号頁・発行日

vol.47, no.7, pp.436-437, 2012-07-25 (Released:2012-09-12)

著者

林 秀美 永渕 尚志 畑辺 康宏 田口 彰 谷口 俊二 竹内 一浩 有可 光宏 仙波 智行 浅野 克彦 河島 巌 寺薗 完一 高祖 聖一 清水 延彦 辰田 昌功 大崎 博之

出版者

公益社団法人 低温工学・超電導学会 (旧 社団法人 低温工学協会)

雑誌

低温工学 (ISSN:03892441)

巻号頁・発行日

vol.40, no.5, pp.167-174, 2005 (Released:2005-10-28)

参考文献数

13

被引用文献数

3 3

---

The authors have developed a solenoid model coil to stabilize the power system in superconducting magnetic energy storage (SMES) system with the aim of drastically reducing system cost. The single solenoid model coil is designed with the rated current, maximum magnetic field and coil charge rates equivalent to those of a practical 100 MW/15 kWh-class SMES using multi-pole solenoid coils. In addition, the coil is characterized by the use of a stabilized Al-NbTi CIC conductor that has a graded structure, layered winding and a high magnetic field with a compact design. To verify coil performance, several tests such as a the measurement of rated current and AC loss, high-speed pulse operation, coil quenching, and insulation characteristics were conducted using a model coil at Kyushu Electric's Imajuku testing center. Test results proved that the SMES model coil performs as well as the initially designed coil, while doing so at a drastically reduced cost.

著者

辺見 努 松井 邦浩 小泉 徳潔 中嶋 秀夫 飯島 亜美 酒井 正弘

出版者

公益社団法人 低温工学・超電導学会 (旧 社団法人 低温工学協会)

雑誌

低温工学 (ISSN:03892441)

巻号頁・発行日

vol.47, no.3, pp.172-177, 2012-03-25 (Released:2012-07-04)

参考文献数

6

被引用文献数

3 3

---

The manufacturing process for ITER toroidal field (TF) coils must be demonstrated as effective in order to meet the criteria for qualification. Since impregnation of the insulation system is one criterion for qualification in this study, we performed impregnation tests using a cyanate-ester/epoxy blended resin, chosen for its excellent resistance to radiation. To establish the insulation and impregnation procedure in the TF coil manufacturing process, three types of trials were performed: 1) impregnation tests using an acrylic model to fix the impregnation conditions; 2) an impregnation test using a metallic model to confirm that no void remains in the insulation layer after curing in the D-shaped configuration; and 3) insulation and impregnation trials using a 1/3-scale double-pancake (DP) model. The results of these trials were used to determine the insulation and impregnation procedures for manufacturing ITER TF coils.