• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2001년도 추계학술대회 논문집 Vol.14 No.1
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• pp.278-280
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• 2001

BSCCO thin films have been fabricated by co-deposition at an ultralow growth rate using ion beam sputtering(IBS) method. The growth rates of the films was set in the region from 0.17 to 0.27 nm/min. MgO(100) was used as a substrate. In order to appreciate stable existing region of Bi 2212 phase with temperature and ozone pressure, the substrate temperature was varied between 655 and $820^{\circ}C$ and the highly condensed ozone gas pressure($PO_3$) in vacuum chamber was varied between $2.0{\times}10^{-6}$ and $2.3{\times}10^{-5}$ Torr. Bi 2212 phase appeared in the temperature range of 750 and $795^{\circ}C$ and single phase of Bi 2201 existed in the lower region than $785^{\circ}C$. Whereas, $PO_3$ dependance on structural formation was scarcely observed regardless of the pressure variation. And high quality of c-axis oriented Bi 2212 thin film with $T_c$(onset) of about 90 K and $T_c$(zero) of about 45 K is obtained. Only a small amount of CuO in some films was observed as impurity, and no impurity phase such as $CaCuO_2$ was observed in all of the obtained films.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2001년도 추계학술대회 논문집
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• pp.278-280
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• 2001

BSCCO thin films have been fabricated by co-deposition at an ultralow growth rate using ion beam sputtering(IBS) method. The growth rates of the films was set in the region from 0.17 to 0.27 nm/min. MgO(100) was used as a substrate. In order to appreciate stable existing region of Bi 2212 Phase with temperature and ozone pressure, the substrate temperature was varied between 655 and 820$^{\circ}C$ and the highly condensed ozone gas pressure(PO$_3$) in vacuum chamber was varied between 2.0x10$\^$-6/ and 2.3x10$\^$-5/ Torr. Bi 2212 Phase appeared in the temperature range of 750 and 795$^{\circ}C$ and single phase of Bi 2201 existed in the lower region than 785$^{\circ}C$. Whereas, PO$_3$ dependance on structural formation was scarcely observed regardless of the pressure variation. And high quality of c-axis oriented Bi 2212 thin film with T$\sub$c/(onset) of about 70 K and T$\sub$c/(zero) of about 45 K is obtained. Only a small amount of CuO in some films was observed as impurity, and no impurity phase such as CaCuO$_2$ was observed in all of the obtained films.

• Journal of Microbiology and Biotechnology
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• 제33권12호
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• pp.1576-1586
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• 2023

Vaccination is the most effective method for preventing the spread of the influenza virus. Cell-based influenza vaccines have been developed to overcome the disadvantages of egg-based vaccines and their production efficiency has been previously discussed. In this study, we investigated whether treatment with forskolin (FSK), an adenylyl cyclase activator, affected the output of a cell-based influenza vaccine. We found that FSK increased the propagation of three influenza virus subtypes (A/H1N1/California/4/09, A/H3N2/Mississippi/1/85, and B/Shandong/7/97) in Madin-Darby canine kidney (MDCK) cells. Interestingly, FSK suppressed the growth of MDCK cells. This effect could be a result of protein kinase A (PKA)-Src axis activation, which downregulates extracellular signal-regulated kinase (ERK)1/2 activity and delays cell cycle progression from G1 to S. This delay in cell growth might benefit the binding and entry of the influenza virus in the early stages of viral replication. In contrast, FSK dramatically upregulated ERK1/2 activity via the cAMP-PKA-Raf-1 axis at a late stage of viral replication. Thus, increased ERK1/2 activity might contribute to increased viral ribonucleoprotein export and influenza virus propagation. The increase in viral titer induced by FSK could be explained by the action of cAMP in assisting the entry and binding of the influenza virus. Therefore, FSK addition to cell culture systems could help increase the production efficiency of cell-based vaccines against the influenza virus.

• 한국전기전자재료학회논문지
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• 제16권3호
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• pp.231-237
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• 2003

RE(Nd, Sm) elements doped (RE/Y)$_{1.8}$B $a_{2.4}$C $u_{3.4}$$O_{7-x}$ [(RE/Y)1.8] high $T_{c}$ superconductors were directionally grown by Top Seed Melt Growth(TSMG) process in air atmosphere. The (001)melt-textured N $d_{1.8}$B $a_{2.4}$C $u_{3.4}$ $O_{7-X}$(Nd1.8) seed crystals were used for achieving the c-axis alignment large grains perpendicular to surface of the samples. The (RE/Y)1.8 SEM micrographs of the melt-textured (RE/Y)1.8 samples revealed that the nonsuperconducting (RE/Y)211 inclusions are uniformly distributed in the superconducting (RE/Y)123 matrix except the region very close to the Nd seed crystal. The microstructure and superconducting properties were investigated by XRD, SEM, TEM and SQUID magnetometer. The Melt-textured (RE/Y)1.8 samples showed an onset $T_{c}$=91K and sharp superconducting transition. Also, the magnetization value of the (RE/Y)1.8 samples were compared with those of Y1.8 sample at 77 K. 77 K. 77 K. 77 K.K.

• 한국전기전자재료학회논문지
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• 제17권3호
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• pp.329-332
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• 2004

ZnO thin films were grown with different plume-substrate angles by pulsed laser deposition (PLD) to control the amount of ablated species arriving on a substrate per laser shot. The angles between plume propagation direction and substrate plane (P-S angle) were 0$^{\circ}$, 45$^{\circ}$ and 90$^{\circ}$. The growth time was changed in order to adjust film thickness. From the XRD pattern exhibiting a dominant (002) and a minor (101) XRD peak of ZnO, all films were found to be well oriented along c-axis. From the AFM image, it was found that the grain size of ZnO thin film was increased, as P-S angle decreased. UV intensity investigated by PL (Photoluminescence) increased as P-S angle decreased.

• 한국초전도저온공학회:학술대회논문집
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• 한국초전도저온공학회 1999년도 제1회 학술대회논문집(KIASC 1st conference 99)
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• pp.43-46
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• 1999

The microstructure of Top Seed Milt-Processed $YBa_{2}$$Cu_{3}$$O_{7-\delta}$ single crystal was studied. It was presumed that the segregation of Y211 is due to the difference of growth rates between a, b axis and c axis in crystal direction. Corn kernel lide structure which was grown by the diffusion of Y211 was observed. At the near corner of the seed crystal, the diagonal line on Y123 cry crystal is formed by the corn kernel like structure.

• 한국결정성장학회지
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• 제10권2호
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• pp.111-115
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• 2000

Ba과 Ti의 금속 유기 화합물을 이용하여 (100) $SrTiO_3$ 기판 위에 $BaTIO_3$ 박막을 코팅-열분해법으로 제조하였다. $450^{\circ}C$에서 사전 열처리한 비정질상의 박막은 $2\times 10^{-4}$ atm으로 조정된 산소 분압 하에서 $700^{\circ}C$ 이상의 온도로 열처리함으로써 결정화되었다. $800^{\circ}C$ 이하에서 제조한 박막의 기판에 수직한 면의 격자상수는 cubic $BaTIO_3$의 a 값에 가까우면 $800^{\circ}C$ 이하에서 제조한 박막의 tetragonal $BaTIO_3$ 의 a 값에 가까 웠다. 박막과 기판의 정렬상태를 XRD $\beta$ scan과 pole-figure로 분석한 결과 $BaTIO_3$ 박막은 $SrTiO_3$ 기판과 에피택시 관계가 있었다. $800^{\circ}C$에서 열처리한 박막의 표면은 0.4${\mu}m$ 정도의 섬 형태의 입자로 구성되어 있었고 약 0.8$\mu\textrm{m}$의 두께를 가진 단면은 구형의 입자가 층을 이루고 있었다.

• 한국자기학회지
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• 제19권4호
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• pp.126-132
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• 2009

Molecular-Beam Epitaxy 방법으로 합성된 MnAs 박막의 물리적 특성을 기판의 종류와 증착 온도에 따라 조사하였으며 더불어 이들 시료의 증착 후 열처리 효과를 조사하였다. 증착 온도가 $600^{\circ}C$일 경우에는 기판의 종류에 관계없이 type-B의 결정 방향성을 보였으나 $200^{\circ}C$ 이하에서 합성한 시료에 대하여는 type-A로 합성되었다. $600^{\circ}C$에서 GaAs(001) 기판에 성장시킨 시료에서는 자기화 용이축 내에서도 특히 한쪽 방향으로 자화가 되어 있음을 확인하였다. 강자성을 보이지 않던 $120^{\circ}C$에서 증착한 MnAs/Si(001)와 실온에서 강자성과 상자성이 공존하였던 $200^{\circ}C$에서 증착한 MnAs/GaAs(001) 시료의 경우 $600^{\circ}C$에서 열처리 하였을때 자기적 특성이 크게 향상되었다.

• 한국전기전자재료학회논문지
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• 제26권12호
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• pp.863-866
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• 2013

SiC crystal ingots were grown on 6H-SiC dual-seed crystals with different surface roughness and different seed orientation by a PVT (Physical Vapor Transport) method. 4H and 15R-SiC were grown on seed crystal with high root-mean-square (rms) value. The polytype of grown crystal on the seed crystal with lower rms value was confirmed to be 6H-SiC. On the other hand, all SiC crystals grown on seed crystals with different seed orientation were proven to be 6H-SiC. The surface roughness of seed crystals had no effect on the crystal structure of the grown crystals. However, the crystal quality of 6H-SiC single crystals grown on the on-axis seed were revealed to be slightly better than that of 6H-SiC crystal grown on the off-axis seed.

• 한국양식학회지
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• 제11권2호
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• pp.231-240
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• 1998

온도와 염분에 대하여 내성이 강하고 대량배양이 쉬워서 조개류의 인공종묘생산시 먹이로서 많이 사용하고 있는 5종의 Tetraselmis (T. tetrathele, T. suecica, T. subcordiformis, T. sp. (Haeundae), T. sp (China)) 중 우리나라 기후 환경에 대향배양이 가장 적합한 종을 선택하기 위핵서 최적 배양환경 (온도, 염분)을 조사하고 이때의 세포크기와 영양성분을 조사하였다. 5종의 Tetraselmis의 세포크기 및 체적은 T. sp. (Haeundea)가 장경 $17.6{\pm}1.87$${\mu}$m, 체적 727${\mu}$$m^3$로 가장 대형종이었으며 중국산 T. sp.가 장경14.6+- 1.46${\mu}$m, 체적 625${\mu}$$m^3$으로 가장 소형종이였다. Tetraselmis는 광염성, 광온성이나 최적성장을 위한 수온과 염분 구간은 각각 24~$30^{\circ}C.$와 27~30%.였다. 5종의 Tetraselmis에서 고수온에 대한 내성은 중국산 Tetraselmis, 저수온데 대한 내성은 T. tetrathele가 높은 것으로 나타났다. 5종의 Tetraselmis중 배양밀도가 가장 높았던 종은 T. suecica였으며, 이 종은 배양 7일째 $24^{\circ}C.$, 30%.에서 세포수가 $141{\times}10^4$cells/ml (s.g.r., 0.3906)로 성장이 가장 좋았다. 5종의 Tetraselmis의 화학성분중 조단백질 함량은 T. suecica가 44.50%로 가장 높게 나타났고 조지방은 해운대산 T. sp.가 7.13%로 높게 나타났다. 필수아미노산은 해운대산 .T.sp.에서 50.40%로 가장 높게 나타났고, 불포화지방산은 중국산 T.sp.에서 11.7%로 가장 높게 나타났다. 5종의 Tetraselmis의 성장과 영양성분 결과로 보아 우리나라에서 대량배양이 가장 적합한 종은 T. seucica임을 알수 있었다.