• 제목/요약/키워드: $J_c$ (B)

검색결과 5,404건 처리시간 0.037초

Anti-microbial Activity of Saussurea lappa C.B. Clarke Roots

  • Chang, Kyung-Mi;Choi, Soo-Im;Chung, Sophia J.;Kim, Gun-Hee
    • Preventive Nutrition and Food Science
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    • 제16권4호
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    • pp.376-380
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    • 2011

  • We investigated the total phenolic and flavonoid contents and the antimicrobial activity of ethanol extracts obtained from Saussurea lappa C.B. Clarke. The ethanol extracts of S. lappa C.B. Clarke were fractionated with various solvents (n-hexane, chloroform, and n-butanol). The antimicrobial activity of S. lappa C.B. Clarke was examined by disc-diffusion and micro-dilution susceptibility assays with six food-borne pathogens, and compared to that of the synthetic antibiotics. It is found that the S. lappa C.B. Clarke ethanol extract and n-hexane fraction have strong activity against B. cereus and V. parahaemolyticus strains compared to ampicillin. The inhibitory concentration ($IC_{50}$) values of hexane fraction against L. monocytogenes, B. cereus, and B. subtilis were 62.5, 250 and 500 ppm, respectively. Therefore, these data suggest that S. lappa C.B. Clarke may be useful as antimicrobial agents against food-borne pathogens.

  • https://doi.org/10.3746/jfn.2011.16.4.376 인용 PDF KSCI

초전도 $MgB_2$ 박막의 온도와 장기장의 변화에 따른 광학적 성질 (Temperature and magnetic field dependent optical properties of superconducting $MgB_2$ thin film)

  • 정종훈;이해자;김경완;김명훈;노태원;;강원남;정창욱;이성익
    • Progress in Superconductivity
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    • 제3권1호
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    • pp.31-35
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    • 2001

  • We investigated the temperature and magnetic field dependent optical properties of a$ MgB_2$ thin film in the far-infrared region. In the superconducting state, i.e. 5 K, we obtained the values of superconducting gap $2\Delta$ ~ 5.2 meV and $2\Delta$ $_{k}$ $B/T_{c}$ ~1.8. Although the value of$ 2\Delta$$B/T_{c}$ was nearly half of the BCS value, the $2\Delta$ seemed to follow the temperature dependence of the BCS formula. Under the magnetic field (H), the superconducting state became suppressed. Interestingly, we found that the normal state area fraction abruptly increased at low field but slowly increased at high field. It did not follow the H-dependences predicted for a s-wave superconductor (i.e. a linear dependence) nor for a s-wave one (i.e. $H^{1}$2/ dependence). We discussed the complex gap nature of $MgB_2$ in comparison with two gap and anisotropic s-wave scenarios.ios.

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ITU-T J.83 ANNEX B의 Parity Checksum Generator를 위한 병렬 처리 구조 (Parallel Processing Architecture for Parity Checksum Generator Complying with ITU-T J.83 ANNEX B)

  • 이종엽;홍언표;하동수;임회정
    • 한국통신학회논문지
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    • 제34권6C호
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    • pp.619-625
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    • 2009

  • 이 논문은 ITU-T Recommendation J.83 Annex B에서 패킷 동기화와 에러 검출을 위해 사용된 패리티 체크섬 생성기의 병렬 구조를 제안한다. 제안된 병렬 처리 구조는 기존의 직렬 처리 구조에서 일어나는 병목현상을 제거하여 패리티 체크섬을 생성하는데 필요한 처리 시간을 상당히 줄여준다. 실험 결과는 제안된 병렬 처리 구조가 16%의 면적증가로 처리 속도를 83.1%나 줄일 수 있다는 것을 보여준다.

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Micromachined Millimeter-Wave Cavity Resonators

  • Song, K.J.;Yoon, B.S.;Lee, J.C.;Lee, B.;Kim, J.H.;Kim, N.Y.;Park, J.Y.;Kim, G.H.;Bu, J.U.;Chung, K.W.
    • 한국전자파학회논문지
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    • 제12권1호
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    • pp.27-36
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    • 2001

  • In this paper, micromachined millimeter-wave cavity resonators ar presented. One-port and two-port cavity resonators at Ka-band are designed using 3D design software, HP $HFSS^{TM}$ ver. 5.5 Cavity resonators are fabricated on Si substrate, which is etched down for the cavity, bonded with a Quartz wafer in which metal patterns for the feeding line coupling slot are formed. One-port resonator shows the resonant frequency of 39.34 GHz, the return loss of 14.5 dB, and the loaded $Q(Q_{L})$ of 150. Two-port cavity resonator shows the resonant frequency of 39 GHz, the insertion and return losses of 4.6dB and 19,9dB, the loaded($Q_{L}$) and unloaded $Q(Q_{U})$) of 44.3 and 107, respectively.

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