Perspective on a Superconducting 30 T/1.3 GHz NMR Spectrometer Magnet

Markiewicz, W.D.; Miller, J.R.; Schwartz, J.; Trociewitz, U.P.; Weijers, H.W.

doi:10.1109/tasc.2005.869663

Cited by 66 publications

(38 citation statements)

References 12 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…It has been already demonstrated that such properties make Bi-2212 a very competitive conductor for high field applications (> 20 T) such as magnets for nuclear magnetic resonance or accelerators [4][5][6][7][8][9], however, in this context, an enhancement of J C of two or three times seems to be still needed to boost the successful use of this superconductor in such applications. This aim has driven the work of several groups, especially in USA -where, besides the research labs, Oxford Superconducting Technology (OST) is a company leader on Bi-2212 round wire fabrication -and in Japan and Korea.…”

Section: Introductionmentioning

confidence: 99%

Large critical current density improvement in Bi-2212 wires through the groove-rolling process

Malagoli¹,

Bernini²,

Braccini³

et al. 2013

Supercond. Sci. Technol.

View full text Add to dashboard Cite

Recently the interest about Bi-2212 round wire superconductor for high magnetic field use has been enhancing despite the fact that an increase of the critical current is still needed to boost its successful use in such applications. Recent studies have demonstrated that the main obstacle to current flow, especially in long wires, is the residual porosity inside these Powder-In-Tube processed conductors which develops in bubbles-agglomeration when the Bi-2212 melts. Through this work we tried to overcome this issue acting on the wire densification by changing the deformation process. Here we show the effects of groove-rolling versus drawing process on the critical current density J C and on the microstructure. In particular, groove-rolled multifilamentary wires show a J C increased by a factor of about 3 with respect to drawn wires prepared with the same Bi-2212 powder and architecture. We think that this approach in the deformation process is able to produce the required improvements both because the superconducting properties are enhanced and because it makes the fabrication process faster and cheaper.

show abstract

Section: Introductionmentioning

confidence: 99%

Large critical current density improvement in Bi-2212 wires through the groove-rolling process

Malagoli¹,

Bernini²,

Braccini³

et al. 2013

Supercond. Sci. Technol.

View full text Add to dashboard Cite

show abstract

“…기존의 구리선을 이용하여 고자장을 발생시키는 방식은 오래전에 한계점에 이르렀고, 현재는 저온 초전도 선재를 사용한 고자장 마그넷을 응용한 산업기기가 개발되었으나, 저온 초전도 선재는 냉각을 위해 액체헬륨을 사용하기 때문 에 냉각비용이 비싸고 무엇보다 자기장의 크기가 커질수록 초전도체로 흘릴 수 있는 전류의 크기가 제한된다는 임계전 류 특성으로 인하여 기존 저온초전도 마그넷의 경우 초고자 장 응용이 불가능하다 [1].…”

Section: 서 론unclassified

Nonlinear Characteristic Analysis of Charging Current for Linear Type Magnetic Flux Pump Using RBFNN

Chung¹,

Park²,

Kim³

et al. 2010

Journal of Korean Institute of Intelligent Systems

View full text Add to dashboard Cite

In this work, to theoretically analyze the nonlinear charging characteristic, a Radial Basis Function Neural Network (RBFNN) is adopted. Based on the RBFNN, an charging characteristic tendency of a Linear Type Magnetic Flux Pump (LTMFP) is analyzed. In the paper, we developed the LTMFP that generates stable and controllable charging current and also experimentally investigated its charging characteristic in the cryogenic system. From these experimental results, the charging current of the LTMFP was also found to be frequency dependent with nonlinear quality due to the nonlinear magnetic behaviour of superconducting Nb foil. On the whole, in the case of essentially cryogenic experiment, since cooling costs loomed large in the cryogenic environment, it is difficult to carry out various experiments. Consequentially, in this paper, we estimated the nonlinear characteristic of charging current as well as realized the intelligent model via the design of RBFNN based on the experimental data. In this paper, we view RBF neural networks as predominantly data driven constructs whose processing is based upon an effective usage of experimental data through a prudent process of Fuzzy C-Means clustering method. Also, the receptive fields of the proposed RBF neural network are formed by the FCM clustering.

show abstract

“…For these reasons, a research for obtaining the higher magnetic field using the HTS magnet is in progress to overcome the limitation of the maximum magnetic field of the LTS magnet. This research is currently conducted in Nuclear Magnetic Resonance (NMR) spectrometer because the magnitude of central magnetic field is significant factor in the NMR spectrometer [1,2]. Moreover, homogeneity of magnetic field is important factor in NMR spectrometer.…”

Section: Introductionmentioning

confidence: 99%

A simulation study on the variation of virtual NMR signals by winding, bobbin, spacer error of HTS magnet

Kim

Lee

Kim

et al. 2016

Progress in Superconductivity and Cryogenics

View full text Add to dashboard Cite

Recently, production technique and property of the High-Temperature Superconductor (HTS) tape have been improved. Thus, the study on applying an HTS magnet to the high magnetic field application is rapidly increased. A Nuclear Magnetic Resonance (NMR) spectrometer requires high magnitude and homogeneous of central magnetic field. However, the HTS magnet has fabrication errors because shape of HTS is tape and HTS magnet is manufactured by winding HTS tape to the bobbin. The fabrication errors are winding error, bobbin diameter error, spacer thickness error and so on. The winding error occurs when HTS tape is departed from the arranged position on the bobbin. The bobbin diameter and spacer thickness error occur since the diameter of bobbin and spacer are inaccurate. These errors lead magnitude and homogeneity of central magnetic field to be different from its ideal design. The purpose of this paper is to investigate the effect of winding error, bobbin diameter error and spacer thickness error on the central field and field homogeneity of HTS magnet using the virtual NMR signals in MATLAB simulation.

show abstract

Perspective on a Superconducting 30 T/1.3 GHz NMR Spectrometer Magnet

Cited by 66 publications

References 12 publications

Large critical current density improvement in Bi-2212 wires through the groove-rolling process

Large critical current density improvement in Bi-2212 wires through the groove-rolling process

Nonlinear Characteristic Analysis of Charging Current for Linear Type Magnetic Flux Pump Using RBFNN

A simulation study on the variation of virtual NMR signals by winding, bobbin, spacer error of HTS magnet

Contact Info

Product

Resources

About