• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1998년도 춘계학술대회 논문집
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• pp.491-493
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• 1998

The SmBa$_2$Cu$_3$O$\sub$x/ single crystals were used as seeds to induced YBCO growth in MTG process. As the result, the large bulk oriented YBCO superconductors were prepared with dimension of plane 21mm and 32mm in diameter and 10mm in height. The typical Jc value of the sample is 6.5${\times}$10$^4$A/$\textrm{cm}^2$ and its flux float force is 4.6N/$\textrm{cm}^2$. The oxygen absorption in large bulk textured YBCO samples in pure oxygen was studied at several constant temperatures. It can be divided into two steps: a chemical reaction step and a diffusion step.

• 한국생물물리학회:학술대회논문집
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• 한국생물물리학회 1999년도 학술발표회 진행표 및 논문초록
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• pp.49-49
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• 1999

$H^{＋}$-ATPases play major roles in various cellular physiology. In order to characterize the effects of heavy metal ions on the activity of $H^{＋}$-ATPases, microsomes were isolated from the roots of tomato grown hydroponically. The activity of microsomal $H^{＋}$-ATPase was measured by an enzyme-coupled assay. H $g^{2＋}$ inhibited the activity of microsomal $H^{+}$-ATPase as a dose-dependent manner, F $e^{3+}$ and Z $n^{2+}$ inhibited the activity although they also blocked the activities of enzymes used in the assay, and C $s^{+}$ and $Ba^{2+}$ showed no significant effect.(omitted)d)ted)d)

• 한국초전도ㆍ저온공학회논문지
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• 제9권2호
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• pp.19-22
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• 2007

We report the phase and microstructure evolutions of metal trifluoroacetate (TFA) precursor films in the TFA-MOD process of YBCO films on the LAO (100) substrates. It was confirmed that the precursor films were decomposed into $Y_2O_3$, $BaF_2$, and CuO nanoparticles after the initial heat treatment up to 400$^{\circ}C$. After a subsequent heat treatment at higher temperatures ranging from 700 to 850$^{\circ}C$ for 2 h, these nano-sized phases are converted into YBCO films. High Jc(77K, sf)-YBCO thin films (over 2 MA/$cm^2$) were successfully fabricated with firing temperatures ranging from 775 to 850$^{\circ}C$ for 2 h, where films were composed of dense microstructures with large grains.

• 한국자원식물학회지
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• 제32권1호
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• pp.53-62
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• 2019

본 연구는 우리나라에 자생하고 있는 비비추속 식물 6종(일월비비추, 주걱비비추, 다도해비비추, 좀비비추, 한라비비추, 흑산도비비추)의 정단을 이용하여 대량증식과 품종개발 등을 위한 기내증식체계를 확립하고자 하였다. 정단은 0.5, 1.0, 2.0, 4.0 mg/L BA와 0.1, 0.5, 1.0, 2.0 mg/L TDZ를 0.1 mg/L NAA와 각각 혼용한 조건과 PGRs을 무첨가한 조건(control)의 MS배지에 배양하였다. 배양 8주 후에 embryogenic callus, somatic embryo, crown bud, 그리고 신초와 뿌리의 분화 및 생육, 생체중 등에 대하여 조사하였다. 6종의 비비추 식물 모두에서 control에 비하여 PGRs 처리구의 embryogenic callus와 somatic embryo 형성율, 다신초 분화율이 높았다. 분화된 신초의 개수는 일월비비추는 2.0 mg/L TDZ에서 5.4개, 주걱비비추와 다도해비비추는 1.0 mg/L TDZ에서 각각 3.3개, 5.8개, 좀비비추는 0.5mg/L BA에서 11.1개, 흑산도비비추는 0.5 mg/L TDZ에서 9.8개, 한라비비추는 1.0 mg/L BA, 0.1 mg/L TDZ에서 8.1개로 가장 많았다. Somatic embryo 형성에서는 다도해비비추와 흑산도비비추가 처리한 PGRs에 대해 효과적이었고, 일월비비추, 주걱비비추, 좀비비추, 한라비비추에서는 상대적으로 효과가 적었다. 4종의 자생 비비추(일월비비추, 주걱비비추, 다도해비비추, 흑산도비비추)에서 조사된 crown bud도 control에 비하여 PGRs 처리구에서 더많이 형성되었다. 주걱비비추는 cytokinin의 종류 및 농도와 상관없이 callus와 신초 분화에 큰 효과가 나타나지 않았지만, crown bud의 형성에는 TDZ에서 약간 증가하였다.

• 한국초전도ㆍ저온공학회논문지
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• 제10권3호
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• pp.5-8
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• 2008

On highly-textured IBAD-MgO templates, we have tried to find proper buffer layers among various candidate materials, including $LaMnO_3$ (LMO), $La_2Zr_2O_7$ (LAO), $LaAlO_3$ (LAO), $LaGaO_3$ (LGO), $NdGaO_3$ (NGO), and $BaZrO_3$ (BZO). All buffer layers were deposited on the IBAD-MgO templates by KrF pulsed laser deposition(PLD). LAO layer showed an armorphous phase. LZO, LGO, and NGO layers showed polycrystalline growth. Only LMO and BZO layers exhibited c-axis oriented biaxially textured films. Optimally processed LMO buffer layer at deposition temperature of $750^{\circ}C$ and $PO_2$ of 100mTorr exhibited ${\triangle}{\phi}$ value of ${\sim}-5.2^{\circ}$ and RMS roughness of 5.6nm. Interestingly, BZO buffer layers with ${\triangle}{\phi}$ values of ${\sim}-6^{\circ}$ could be routinely produced over a wide PLD processing condition.

• 한국자기학회지
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• 제14권1호
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• pp.38-44
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• 2004

초거대 자기저항 물질인 페롭스카이트 구조의 망간 산화물 L $a_{0.67}$B $a_{0.33}$M $n_{1-x}$ F $e_{x}$ $O_3$(이하 LBMFO)에 대하여 에탄올을 용매로 한 졸겔법을 이용하여 미량의 철을 치환한 단일상의 LBMFO산화물 분말을 제조하였다. 결정학적 및 자기적 성질을 x선 회절법, 시료진동형 자화율 측정기(VSM), 중성자 회절 실험, 러더포드 후방 산란법, Mossbauer 분광법 및 자기저항 측정을 통하여 연구하였다. X-선 및 중성자 회절실험 분석 결과 결정학적 구조는 Pnma의 공간구조를 갖는 orthorhombic구조로 분석되었다. 미량의 철이 치환됨에 따라 격자상수 $a_{0}$ , $c_{0}$ 는 증가하며, $b_{0}$ 는 감소하는 경향을 보였다. VSM측정결과 포화 자화값과 보자력은 철의 치환량이 증가함에 따라서 각각 감소하는 경향을 보였다. 큐리(Curie)온도는 철의 치환량이 증가함에 따라서 360 K에서 점차 감소하는 경향성을 나타내었다. 철을 1 % 치환한 경우 1T 인가자장 하에 최대자기저항변화의 비($\Delta$$\rho$/$\rho$$_{H}$)는 281 K에서 9.5%였으며, 금속-반도체 전이 온도는 253 K로 관측되었다. Mossbauer 스펙트럼 분석결과 15 K에서 날카로운 Lorentzian 12 line(2 set)의 공명 흡수선으로 측정되었다. 이성질체 이동 값으로부터 미량 치환된 $^{57}$ Fe이온의 전자 상태는 +3가 임을 알 수 있었다.는 +3가 임을 알 수 있었다.

• Progress in Superconductivity
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• 제2권2호
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• pp.92-96
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• 2001

We have fabricated a modified hairpin-type YBa$_2$Cu$_3$O$_{7-{\delta}}$ (YBCO) 2-pole microstrip bandpass filter with the center frequency of 5.8 GHz. We designed a hairpin-type filter with interdigital-coupled inner poles to improve the filter performance. Compared to a typical hairpin-type filter of the same size, the center frequency, the bandwidth and the insertion loss appeared smaller by 14.5% ,29.6%, and 0.55 dB, respectively. The dimensions of the filter were 13.7mm ${\times}$3.3 mm. YBCO films deposited on r-cut sapphire buffered with a CeO$_2$thin layer were used fur making the filter.

• 한국의학물리학회:학술대회논문집
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• 한국의학물리학회 2003년도 제27회 추계학술대회
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• pp.75-75
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• 2003

Purpose: To investigate whether or not acupuncture of GB34 produces a significant response of the modulation of somatomotor areas by functional magnetic resonance imaging (fMRI) study. Methods: The acupoint, GB34, located in the back of the knee, is known to be effective in recovering motor function after stroke. Using 3T MRI scanner, functional MR imaging of the whole brain was performed in 12 normal healthy subjects during two stimulation paradigms; acupuncture manipulation on GB 34 and sham points. This study investigates the activation of the motor cortex elicited by a soft and an intensified stimulation of GB 34. Three different paradigms were carried out to detect any possible modulation of the Blood Oxygenation Level Dependent (BOLD) response in the somatomortor area to motor stimulation through acupuncture. Results: Group analysis from seven individuals showed that bilateral sensorimotor areas (BA 3,4,6 and 7) showed stimulation related BOLD signal contrast of approximately 6% whereas very few areas were activated when sham stimulation is given. Conclusions: The present study shows that acupuncture fMRI study can be safely conducted in 3T MRI environment, and acupuncture stimulation in GB34 modulates the cortical activities of the soma- to motor area in human. The present findings may shed light on the CNS mechanism of motor function by acupuncture and form a basis for future investigations of motor modulation circuits in the stroke patients. Acknowledgement: This study was supported by a grant of the Mid and Long Term Nuclear RID Plan Program, Ministry of Science and Technology, Republic of Korea.

• 한국의학물리학회:학술대회논문집
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• 한국의학물리학회 2002년도 Proceedings
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• pp.352-355
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• 2002

The purpose of this study was to investigate whether or not acupuncture of GB34 produces a significant response of the modulation of somatomotor areas by functional magnetic resonance imaging (fMRI) study. The acupoint, GB34, located in the back of the knee, is known to be effective in recovering motor function after stroke. Using 3T MRI scanner, functional MR imaging of the whole brain was performed in 12 normal healthy subjects during two stimulation paradigms; acupuncture manipulation on GB 34 and sham points. This study investigates the activation of the mortor cortex elicited by a soft and an intensified stimulation of GB 34. Three different paradigms were carried out to detect any possible modulation of the Blood Oxygenation Level Dependent (BOLD) response in the somatomortor area to motor stimulation through acupuncture. Group analysis from seven individuals showed that bilateral sensorimotor areas (BA 3,4,6 and 7) showed stimulation related BOLD signal contrast of approximately 6% whereas very few areas were activated when sham stimulation is given. The present study shows that acupuncture fMRI study can be safely conducted in 3T MRI environment, and acupuncture stimulation in GB34 modulates the cortical activities of the somatomotor area in human. The present findings may shed light on the CNS mechanism of motor function by acupuncture and form a basis for future investigations of motor modulation circuits in the stroke patients.

• 한국대기환경학회지
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• 제14권6호
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• pp.631-642
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• 1998

Fall-out particles were collected by the modified British deposit gauges at 35 sampling sites in Suwon area from January to November, 1996. Twenty chemical species (Al. Ba, Cd, Cr, K, Pb, Sb, Zn, Cu, Fe, Ni, V, F-, Cl-, NO3-, 5042-, Na+, NH4+, Mg2+, and Ca2+) were analyzed by AAS and If. The purposes of this study were to estimate qualitatively various emission sources of the fell-out particle by applying multivariate statistical techniques such as factor analysis, multiple regression analysis, and discriminant analysis. During the study, outlier sites were determined by a z-score method. Cl-, Na+, Mg2+, and SO42- were highly correlated due to their common marine related source. Wind speed was the most influential factor for the deposition fluxes of the particle itself and all the chemical species as well. When applying the factor analysis, 8 source patterns were qualitatively obtained, such as marine source, soil source, oil burning source, Cr related source, tire source, Cd related source, agriculture source, and F- related source. As a result of the multiple regression analysis, we could suggest that some chemical compounds may possibly exist in the form of CaSO4, NaN03, NaCl, MgC12, (NH4)2SO4, NaF, and CaCl2 in the fall-out particles. Finally, spatial and seasonal classification study performed by a discriminant analysis showed th.at SO42-, Ca2+, Cl-, and Fe were dominant in the group of spatial pattern; however, SO42-, Cl-, Al, and V were in the group of seasonal pattern.