• Journal of the Korean Crystal Growth and Crystal Technology
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• v.7 no.4
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• pp.555-559
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• 1997

Lead scandium niobate $Pb(Sc_{1/2}Nb_{1/2})O_3$ powders were prepared by the sol-gel method using lead acetate, scandium acetate, and niobium isopropoxide as precursors. Crystallization behavior and phase formation were investigated for gel-derived powders. After the calcination at $700^{\circ}C$ for 1 hr, $Pb(Sc_{1/2}Nb_{1/2})O_3$ powder with the purity of 97% was formed and the average particle size of powder was below 0.2 $\mu \textrm{m}$.

• Journal of Environmental Science International
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• v.6 no.2
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• pp.189-194
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• 1997

Toxic peptides from hornet venom, mastoparan and mastoparan-B were synthesized us- ing the solid phase peptide synthesis method and investigated the interaction of them with phospholipid bilayer, antibacterial activity, and hemolytic activity. Both toxic peptides could induce dye release at a low concentration in neutral liposome. The binding affinity of mastoparan-B for neutral liposome was smaller than that for acidic one. Mastoparan and mastoparan-B had strong antibacterial activity for gram-positive bacteria, but weak or potent activity for gram-negative ones, respectively. Mastoparan and mastoparan-B lysed erythrocyte very little up to 5 $\mu$M.

• Bulletin of the Korean Chemical Society
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• v.23 no.11
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• pp.1623-1628
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• 2002

Tetracyclic pyrido[2,3-b]azepine derivatives 4a-d and 4f as analogues of mirtazapine were synthesized via N-acyliminium ion cyclization by using aromatic rings such as benzene and thiophene ring as a ${\pi}-nucleophile$, and evaluated for the binding affinity for ${\alpha}2-adrenoceptor$. Among tested compounds, 2,3,9,13b-tetrahydro-1H-benzo[f]pyrrolo[2,1-a]pyrido[2,3-c]azepine (4a) was the most potent (Ki = 0.26 ${\mu}M)$ but showed about 3-fold less binding affinity than mirtazapine (Ki = 0.08 ${\mu}M)$ for a2-adrenoceptor.

• Proceedings of the Korean Society of Food Hygiene and Safety Conference
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• 2002.05a
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• pp.147-147
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• 2002

This experimental study was carried out to investigate on the safety of Nog-yong aqua-acupuncture solution in primary culture of adult rat hepatocytes. Primary culture of adult rat hepatocytes has been considered as a ideal model for toxicological studies because cultured hepatocytes maintained many liver-specific functions. In this research, we investigated the effects of Nog-yong aqua-aqupunture(1-10$\mu\textrm{g}$/ml) on cytotoxicites in primary culture of adult rat hepatocytes using LDH release assays. Hepatic glutathione level. glutathione-S-transferase activity, and albumin synthesis were not affected by treatment with Nog-yong aqua-aqupuntur alone. Nog-yong aqua-aqupuncoure solution(0.5-$10{\mu}\textrm{g}$/ml) on cytotoxicites in primary culture of adult rat hepatocytes using LDH release not significantly affected normal functional charaterists.

• Bulletin of the Korean Chemical Society
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• v.32 no.4
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• pp.1293-1297
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• 2011

To improve the biological activities of rupestonic acid, 21 new rupestonic acid fatty ester derivatives (2a-2h) and aromatic ester derivatives (2i-2u) were synthesized and preliminarily evaluated for their anti-influenza activity in vitro by the national center for drug screening of China, using the Oseltamivir and Ribavirin as reference drugs. The results showed that 2l ($IC_{50}=0.5{\mu}mol/L$) exhibited potent anti-influenza $A_3$ viral activity among the synthesized compounds and was 10-fold more potent than that of the reference drug Oseltamivir ($IC_{50}=5.1{\mu}mol/L$).

• Proceedings of the Korean Vacuum Society Conference
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• 2013.02a
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• pp.138-138
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• 2013

Ni-CeO2 및 Ni-MgO와 같이 Ni이 포함된 나노복합물질을 고주파 유도결합 플라즈마를 이용하여 합성하였다. 이를 위해, 먼저, 1~100 ${\mu}m$ 크기의 가상 Ni 입자와 고융점 세라믹 입자가 플라즈마 유동 내에서 겪는 열전달 과정을 수치해석을 통해 묘사하였다. 묘사 결과로부터, 완전 기화한 Ni 증기가, 채 기화하지 못하고 고체 형태로 남은 세라믹 입자 위에서 균일하게 응축된 형태를 갖는 Ni-세라믹 나노입자 합성을 예측하고, 실제 합성 실험을 25 kW 급 고주파 유도결합 플라즈마에 0.1~10 ${\mu}m$ 크기의 Ni, CeO2 및 MgO 분말을 주입하여 수행하였다. 마지막으로, 실험을 통해 합성된 Ni 계 복합나노물질에 대해, FE-SEM 및 TEM 사진 분석과 EDS 및 ICP-AES 성분 분석을 진행하고, 수치해석을 통해 예측된 결과와 비교 검토하였다.

• Journal of the Korean Graphic Arts Communication Society
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• v.14 no.1
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• pp.1-15
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• 1996

In this paper, the preparation of lead zirconium titanate(PZT) thin film by sol-gel processing was descried. Thin film coated with thickness of 4${\mu}{\textrm}{m}$ on the stainless steel substrates using the multiple spin-coating process. The crystalline phases of PZT powder and film were investigated by X-ray diffraction pattern and PZT thin film has perovskite structure over 600 C annealing temperature. Corona charging characteristics of the ferroelectric PZT thin film at 600 C were investigated by electrophotographic measurement. A difference in the charging characteristics between positive and negative corona charging was found. The charge acceptance depended in the polarity of corona and the poling of film. According to the D-E hysteresis measurment, PZT thin film can be poled by corona charging without use of top electrode. The remnant polarization in the PZT thin film is generally in the order of 48$\mu$C/$\textrm{cm}^2$. From this results, the ferroelectric PZT thin film will be possible to apply for the add-on type imaging formation.

• Korean Chemical Engineering Research
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• v.44 no.3
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• pp.243-247
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• 2006

MFI zeolite membranes were prepared on anodic alumina (Anodisc) as support. First, silicalite-1(${\approx}1.2{\mu}m$) seed crystals were attached to the surface of the support via chemical bonding, and the a- and b-axis oriented zeolite membranes could be synthesized on the support coated with the monolayer of the seed crystals by secondary growth hydrothermal synthesis. The zeolite membranes prepared were characterized using scanning electron microscope and analyzed by X-ray diffraction.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.6 no.2
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• pp.254-262
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• 1996

$Pb(Zr_{0.52}Ti_{0.48})O_{3}$ (PZT) ceramics were prepared with uniform particle size of $1~3\;\mu\textrm{m}$ by hydrothermal synthesis at various conditions, such as hydrothermal reaction temperature, concentration of mineralizer and reaction time. PZT ceramics were formed above $180^{\circ}C$ for 2 hrs reaction using 10 M KOH solution as a mineralizer, but reaction condition was slightly different by starting materials. Morphology and characterization of PZT powders were investigated by XRD and SEM. By increasing the reaction temperature, KOH concentration and reaction time, the composition of the PZT phase tended to be homogeneous phase.

• Toxicological Research
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• v.19 no.1
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• pp.33-37
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• 2003

Asiaticoside has been tested for the ability as an anti-inflammatory drug using lipopolysaccharide (LPS)-stimulated macrophage cell line (RAW 264.7 cell). LPS treatment induced dramatically inducible nitric oxide synthase (iNOS) in RAW cells. However, asiaticoside inhibited LPS-stimulated iNOS induction in a concentration-dependent manner. Especially, higher concentrations (＞50 $\mu\textrm{M}$) of asiaticoside completely blocked iNOS induction. In addition, LPS-stimulated expression of inducible cyclooxygenase (COX-2) and interleukin-1 $\alpha$ (IL-1 $\alpha$) was inhibited by asiaticoside treatment. Asiaticoside up to 50 $\mu\textrm{M}$ still required to inhibit COX-2 and IL-1 $\alpha$ induced by LPS. Consistent with these findings, treatment with asiaticoside suppressed do novo synthesis and cellular accumulation of prostaglandin $E_2$ to a lesser extent, suggesting that asiaticoside blocked the induction as well as the activity of COX-2 These results suggest the possibility that asiaticoside may be effective therapeutic agents for septic shock and other inflammatory diseases.