• Bulletin of the Korean Chemical Society
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• 제30권12호
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• pp.3016-3020
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• 2009

The chemical bond parameters of Y-123, Eu-123, Pr-123 and Gd-123 compounds have calculated using the chemical bond theory of complex crystals. Their hardness have been predicted by the chemical bond definition of hardness. The calculated results indicate that the Ba-O and RE-O types of bond have a lower covalent character and the Cu-O types of bond have greater covalency. The hardness values increase as the unit cell volume of the rare earth superconductor structures decrease.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2007년도 하계학술대회 논문집 Vol.8
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• pp.243-243
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• 2007

We have studied the electrical properties and microstructure of $(Y_{0.5}Nd_{0.25}Sm_{0.25})Ba_2Cu_3O_y[(YNS)-123]$ Oxides by rod-type seeded melt growth process(RSMG) in air atmosphere. Rod-type $NdBa_2Cu_3O_y${Nd-123) seed crystals made a extrusion process method, were used for achieving the ab-plane alignment having large grains perpendicular to the center of (YNS)-123 samples. The observations using SEM and TEM micrographs of the melt-textured (YNS)-123 samples revealed that the nonsuperconducting $(Y_{0.5}Nd_{0.25}Sm_{0.25})Ba_2Cu_3O_y[(YNS)-211]$ inclusions are uniformly distributed in the superconducting matrix. The microstructure and electrical properties were investigated by XRD, SEM, TEM and DC SQUID magnetometer. The sample showed a sharp superconducting transition at 90 K. The magnetization values of the (YNS)-123 sample exhibited the enhanced electrical properties, compared with $YBa_2Cu_3O_y$(Y-123) sample.

• 한국응용약물학회:학술대회논문집
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• 한국응용약물학회 1996년도 춘계학술대회
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• pp.191-191
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• 1996

BQ-123, a selective $ET_{A}$ receptor antagonist, reverses various responses induced by Endothelin-1 and it has been reported that BQ-123 ameliorates the cerebrovascular constriction, hypertension, and decrease of blood flow. Previously, we announced that the level of Endothelin-2 increase in the brain and spinal cord of EAE-induced lewis rat and showed the origin of ET-1 is activated macrophages. Intracisternal injection of $ET_{A}$ receptor antagonist, BQ-123(10nmol) was done for visualizing the role of endothelin-1 on the pathogenesis of EAE. BQ-123 apparently blocked the severity of clinical score of EAE and decreased the histologically observed inflammatory region. The blocking effect on the progression of EAE model following BQ-123, suggests that BQ-123 is a physiological antagonist in terms of development of the sign of multiple sclerosis.

• 대한핵의학회지
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• 제26권1호
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• pp.116-123
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• 1992

$^{123}I$ has ideal half life of 13 hours, suitable 159 keV gamma energy for imaging, and easy labeling methods. In Korea Cancer Center Hospital, $^{123}I$ has been produced by MC-50 cyclotron. The purpose of this study is looking for good labeling condition of $^{123}I$ and $^{99m}Tc$ to nonspecific human polyclonal IgG, and comparing these with $^{67}Ga-citrate$ in the abscess bearing mice. Human polyclonal nonspecific IgG was labeled with 0.2 M phosphate buffer added $^{123}I$ by chloramine T method. Human polyclonat nonspecific IgG was labeled with $^{99m}Tc-gluconate$ after activation with $\beta-mercaptoethanol$. In the abscess bearing mice, the radioactivity in the abscess was higher in 24 hours than 6 hours after injection. In the abscess, $^{123}I$ nonspecific IgG had higher uptake than $^{99m}Tc-IgG\;or\;^{67}Ga-citrate$. There was no significant difference in absecess uptake of $^{123}I-IgG$ among 24, 72, 120 hours abscess age. Further clinical researches with $^{123}I-nonspecific$ IgG, and other immunoscintigraphies using $^{123}I$ are expected.

• 한국재료학회지
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• 제8권12호
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• pp.1082-1089
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• 1998

$YBa_2$$Cu_3$$O_{7-y}$ (123) 초전도체에서 은 입자의 미세분산을 얻고자 말릭산을 사용한 발화합성과 고상반응법으로 123와 123-Ag 복합 초전도분말을 제조하였다. 발화합성분말을 원료로 사용할 시 마이크론 미만의 미세한 123 분말과 은 분말의 복합체를 얻을 수 있었다. 원료로 사용된 산화은($Ag_2O$) 분말은 발화합성과정 중금속 은으로 환원되었다. 원료분말에 첨가된 금속 은에 의한 반응 물질간의 확산 촉진으로 123상이 단시간내에 생성되었고 입자성장도 촉진되었다. 발화합성법으로 제조한 시편은 기계적 혼합공정으로 제조한 시편에 비해 은 입자들은 미세하게 분산시킬 수 있어서 초전도체의 임계전류밀도가 향상되었다.

• 한국결정성장학회지
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• 제15권4호
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• pp.141-144
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• 2005

[ $(Y_{0.5}Sm_{0.25}Nd_{0.25})Ba_2Cu_3O_y$ ] [(YSN)-123] high $T_c$ composite superconductors with $CeO_2$ addition were systematically investigated by top seeded melt growth (TSMG) process in air atmosphere. A melt textured $NdBa_2Cu_3O_y$ (Nd-123) single crystal was used as a seed for achieving the c-axis alignment large grains perpendicular to the surface of (YSN)-123 composite oxides. The size of $(Y_{0.5}Sm_{0.25}Nd_{0.25})_2BaCuO_5$ [(YSN)211] nonsuperconducting inclusions of the melt textured (YSN)-123 samples with $CeO_2$ addition were remarkably reduced and uniformly distributed within the (YSN)123 superconducting matrix except in the region very close to the Nd-123 seed crystal. The sample showed a sharp superconducting transition of 91 K.

• Transactions on Electrical and Electronic Materials
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• 제6권6호
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• pp.284-288
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• 2005

We have systematically studied the superconducting properties and flux pinning enhancement of $(Y_{0.33}Sm_{0.33}Nd_{0.33})\;Ba_2Cu_3O_y$ [(YSN)-123] composite oxides by melt growth process in air. A sample prepared by this method showed well-textured microstructure, and $(Y_{0.33}Sm_{0.33}Nd_{0.33})\;BaCuO_5$ [(YSN)211] nonsuperconducting particles were uniformly dispersed in large (YSN) 123 superconducting matrix. The sample showed a sharp superconducting transition at 91 K. The magnetization measurements of the (YSN)-123 sample exhibited the enhanced flux pinning, compared with $YBa_2Cu_3O_y$ (Y-123) sample without Sm and Nd. Critical current densities of (YSN)-123 sample was $2.5{\times}10^4 A/cm^2$ at 2 T and 77 K.

• 대한핵의학회지
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• 제35권5호
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• pp.324-333
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• 2001

목적: $^{123}I$ 표지된 지방산 유도체는 심근에너지대사를 평가하는데 사용되어 왔다. 본 연구는 $^{123}I$-BMIPP를 지방육종 진단물질로서의 유용성을 평가하기 위하여, 지방육종 세포주와 신경교종 세포주간의 시험관내의 섭취율을 비교하고 지방육종 형성 nude mice 동물모델에서의 생체분포와 생체영상을 확인하였다. 대상 및 방법: Cold-BMIPP에 $^{123}I$의 표지는 $Cu^{2+}$를 촉매로 이용하여 반응 후 Sep-pak으로 분리정제하여 TLC를 이용하여 방사화학적 순도를 확인하였다. 시험관내 섭취율 시험은 $^{123}I$-BMIPP를 지방육종 세포주인 SW872와 신경교종 세포주인 9L에 각각 시간대별로 5분, 15분, 30분, 60분, 120분, 180분씩 처리한 후 섭취율을 비교하였다. 정상 백서에서의 생체분포를 평가하기 위하여 18시간 금식시킨 군(n=6/군)과 식이를 한 군으로하여 $^{123}I$-BMIPP를 꼬리정맥에 주사하고 30분, 2시간, 24시간후의 각 장기별 방사능을 감마카운터로 계측하였다. 지방육종 세포주인 SW872를 왼쪽 대퇴부에 피하접종한후 종양이 형성된 누드마우스(n=5/군)를 18시간 금식시키고 $^{123}I$-BMIPP를 주사한 후 30분, 2시간, 24시간후의 생체분포와 2시간, 24시간의 생체영상을 평가하였다. 결과: $^{123}I$-BMIPP의 표지수율은 95 % 이상이었으며, 방사화학적 순도는 99 % 이상이었다. 지방육종 세포주인 SW872가 신경교종 세포주인 9L보다 180분에서 1.5배 정도의 섭취율의 증가를 나타내었다. 정상 백서에서의 생체분포를 확인한 결과, 24시간에서 금식을 한 경우가 식이를 한 경우보다 방사성표지 지방산의 제거율이 지연됨을 알 수가 있었으며 주요 배출장기는 위장관으로 확인되었다. 지방육종이 형성된 누드마우스에서 각 시간대별로 Tumor/Blood 비율은 0.94, 0.75, 1.38이었고, Tumor/Muscle의 비율은 0.66, 1.53, 1.11을 나타내었다. 24시간의 감마카메라영상에서 지방육종으로의 국소적인 집적이 확인되었다. 결론: 이상의 결과를 종합해볼 때 지방육종에서 $^{123}I$-BMIPP를 지방육종 영상물질로서의 사용 가능성을 확인할 수 있었다.

• 한국분말재료학회지
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• 제8권2호
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• pp.117-123
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• 2001

Formation of pores in melt-processed $YBa_2Cu_3O_{7-x}$ (123) oxides and its effect on the microstructure were studied. Spherical pores with a size of a few tens of microns were formed due to the evolution of oxygen gas during melting of a 123 oxide. Some of pores were converted into liquid pockets by liquid filling, but others remained unfilled. The liquid pockets were converted into spherical 123 regions with a lower $Y_2BaCuO_5$ (211)density through the peritectic reaction during subsequent cooling, while the pores were entrapped into the periteictically grown 123 grains. The spherical 123 regions often consists of a residual melt due to the unbalanced peritectically reaction.

• 레미콘
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• 1호통권54호
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• pp.123-123
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• 1998