• 제목/요약/키워드: Applied Research

검색결과 38,374건 처리시간 0.071초

내부 확산법에 의한 $Nb_{3}Sn$ 초전도 선재에서 부분 가열이 초전도 특성에 미치는 영향 (The effect of local heating on superconductivities in internal tin Processed $Nb_{3}Sn$ wires)

  • 하동우;오상수;하홍수;이남진;권영길;류강식
    • 대한전기학회:학술대회논문집
    • /
    • 대한전기학회 1999년도 추계학술대회 논문집 학회본부 C
    • /
    • pp.876-878
    • /
    • 1999
  • Internal tin processed Nb3Sn wires with different diameter were locally heated before reaction heat treatment. Local heating at the intermediate state of drawing process decreased the superconducting properties and workability. When the local heating temperatures were higher than melting point of Sn, non-Cu Jc's decreased significantly.

  • PDF

Streptomyces sp.no. 46이 생산하는 살충성 물질의 구조 동정 (Identification of insecticidal compounds from Streptomyces sp. no. 46)

  • 오세량;이형규;구본탁;최수근;박상구;신병식;박승환;김정일
    • Applied Biological Chemistry
    • /
    • 제37권2호
    • /
    • pp.110-114
    • /
    • 1994
  • 토양에서 분리된 방선균에서 생산되는 살충성 물질을 스크리닝하는 연구과정중 선발된 no. 46균주가 생산하는 살충성 물질을 분리하였다. 분리된 물질 4가지는 UV, $^1H-NMR$, $^{13}C-NMR$, C-H COSY 방법으로 구조 분석한 결과, Piericidin $C_1$, $C_2$, $C_3$ 그리고 $D_1$으로 각각 동정되었다.

  • PDF

16 Tesla급 초전도 마그네트의 설계 (Design of 16 Tesla Superconducting Magnet)

  • 권영길;조진욱;이언용;진홍범;하동우;오봉환;류경우;오상수;류강식
    • 대한전기학회:학술대회논문집
    • /
    • 대한전기학회 1995년도 하계학술대회 논문집 A
    • /
    • pp.141-143
    • /
    • 1995
  • The design of a 16 tesla/ 45mm bore superconducting magnet is presented. The system consists of an 8.2 tesla(at 4.2K) outer NbTi coil with a bore I.D. of 261mm, a winding O.D. of 453mm and the length of 430mm which is connected in series with a 5.6 tesla(at 4.2K) middle and a 4.7 tesla(at 4.2K) inner insert coil constructed of multifilamentary $Nb_{3}Sn$. The middle and inner insert coil will be reacted after winding. Also, epoxy impregnation will be accomplished at $Nb_{3}Sn$ coils using a low viscosity crack resistant epoxy which is forced into the coil with a series of vacuum and over atmosphere pressure cycle.

  • PDF

68 cm 상온 보아를 갖는 MRI용 초전도마그네트에 관한 연구 (The Study on the Superconducting MRI Magnet of 68 cm in Room Temperature Bore)

  • 진흥범;오봉환;조전욱;오상수;권영길;하동우;이언용;김해종;김옥곤;최병주;류강식
    • 대한의용생체공학회:학술대회논문집
    • /
    • 대한의용생체공학회 1996년도 추계학술대회
    • /
    • pp.142-146
    • /
    • 1996
  • In this paper, we present the main research results on the 2 Tesla class - superconducting MRI magnet which we have developed. Multi section type superconducting MRI main coil and various superconducting shims were designed and fabricated for obtaining the high field homogeneity, which is requested in the MR imaging. After assembling the magnet with room temperature bore cryostat field homogenity has been measured and analyzed by NMR field mapping system. According to this, field homogeneity of 22 ppm / 30 cm dsv was confirmed.

  • PDF

The effect of mechanical working on processing the Bi-2223/Ag tapes using PIT method

  • Oh, S.S.;Ha, D.W.;Kim, S.C.;Bae, S.W.;Kwon, Y.K.;Ryu, K.S.;Ha, H.S.
    • 한국초전도학회:학술대회논문집
    • /
    • 한국초전도학회 2000년도 High Temperature Superconductivity Vol.X
    • /
    • pp.276-279
    • /
    • 2000
  • When high temperature superconducting tapes is fabricated using the PIT (Powder In Tube) method, the length of HTS tapes is increased more than 500 ${\sim}$ 1,000 times of initial powder packed billet. On mechanical processing, heterogeneous properties between the ceramic superconducting core and Ag/Ag alloy sheath occur the non-uniformity deformation as like sausaging that deteriorate the critical current properties of HTS tapes. In this study, we investigated the workability of Bi-2223/Ag/Ag alloy sheath tapes fabricated by the PIT method involving a number of different mechanical processes, multi drawing and rolling. In order to obtain the high critical current density and high uniformity of Bi-2223/Ag sheath tapes, the influences of powder packing density, drawing die angle and rolling parameters were studied. We found that the roll diameter is an important variable in the rolling process, as critical current of tapes rolled using 250 mm rolls was higher than that using 150 mm rolls.

  • PDF

고온초전도 코일 제작을 위한 겁합특성 연구 (A Study on Joint Characteristics for High Tc Superconducting Coils)

  • 손명환;김석환;백승규;조영식;서무교;이언용;권영길
    • 대한전기학회:학술대회논문집
    • /
    • 대한전기학회 2002년도 하계학술대회 논문집 B
    • /
    • pp.741-743
    • /
    • 2002
  • Some different types of joining between two parallel high Tc superconducting tapes were prepared and I-V characteristic curves were obtained at the atmosphere of liquid nitrogen. Resistances in joint parts were estimated from I-V curves. We selected the best jointing method among these methods and its resistance were obtained at 28K. The availability of this joint method for fabricating HTS field coils is discussed.

  • PDF