• Bulletin of the Korean Chemical Society
• /
• 제35권4호
• /
• pp.1182-1190
• /
• 2014

$Cd_{1-x}Zn_xS$-sensitized $K_4Nb_6O_{17}$ composite photocatalysts (designated $Cd_{1-x}Zn_xS/K_4Nb_6O_{17}$) were prepared via a simple deposition-precipitation method. The samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy dispersive X-ray spectrometry (EDS), $N_2$ sorption, ultraviolet-visible light diffuse reflectance spectroscopy (UV-Vis DRS), photoluminescence measurements (PL), and X-ray photoelectron spectroscopy (XPS). The $Cd_{0.8}Zn_{0.2}S$ particles were scattered on the surface of $K_4Nb_6O_{17}$, and had a relatively uniform size distribution around 50 nm. The absorption edge of $K_4Nb_6O_{17}$ was shifted to the visible light region and the recombination of photo-generated electrons and holes suppressed after $Cd_{0.8}Zn_{0.2}S$ loading. The $Cd_{0.8}Zn_{0.2}S$(25 wt %)/$K_4Nb_6O_{17}$ composite possessed the highest photocatalytic activity for hydrogen production under visible light irradiation, evolving 8.278 mmol/g in 3 h. Recyclability tests were performed, and the composite photocatalysts were found to be fairly stable. The mechanism of charge separation between the photogenerated electrons and holes at the $Cd_{0.8}Zn_{0.2}S/K_4Nb_6O_{17}$ composite was discussed.

• 한국산림과학회지
• /
• 제97권6호
• /
• pp.582-588
• /
• 2008

성숙한 28년생 상수리나무 임분을 대상으로 5수준의 복합비료[3:4:1처리구(100 kg N/ha, 130 kg P/ha, 33 kg K/ha), 6:4:1, 2:2:1, 3:8:1, 3:4:2]와 무시비구(대조구)를 설치하고 3년간 연속 시비처리한 후 낙엽낙지량 변화를 조사한 결과, 엽량의 경우 3:4:1처리구가 4,015 kg/ha/yr으로 3:8:1처리구의 2,874 kg/ha/yr에 비해 유의적으로(P<0.05) 높았다. 그러나 나머지 시비처리구인 2:2:1, 3:4:2, 6:4:1처리구의 경우 대조구와 유의적인 차이(P>0.05)가 없었다. 총 낙엽낙지량의 경우 3:8:1처리구 4,206 kg/ha/yr, 2:2:1처리구 4,992 kg/ha/yr, 6:4:1처리구 5,372 kg/ha/yr, 무시비구 5,456 kg/ha/yr, 3:4:1처리구 5,840 kg/ha/yr, 3:4:2처리구 6,015 kg/ha/yr 순으로 나타났으며 3:8:1처리구가 타 시비처리구나 대조구에 비해 유의적으로(P<0.05) 작게 유입되었다. 총 낙엽낙지량에 대한 엽량의 비율은 3:4:1, 6:4:1, 3:8:1처리구의 경우 약 66%이상으로 대조구 61%에 비해 높게 나타났다. 본 연구결과에 따르면 성숙한 상수리나무 임분의 낙엽낙지량은 여러 가지 시비수준별 차이가 있는 것으로 나타났다.

• Preventive Nutrition and Food Science
• /
• 제7권4호
• /
• pp.437-441
• /
• 2002

Rice proteins were extracted from brown and milled rice of five varieties: Kwanganbyeo, Daeanbyeo, Daejinbyeo, Surabyeo, Hwaseongbyeo; and their electrophoretic patterns were analyzed by SDS-PAGE. Albumin was extracted with water, globulin with 5% NaCl, prolamin with 70% ethanol, and glutelin with 0.2 M sodium borate buffer (pH 10.0) containing 0.5% SDS, 0.6% $\beta$-mercaptoethanol. The ratios of albumin : globulin : prolamin : glutelin in the brown rice were 10.8~14.1 : 12.4~16.4 : 3.6~5.3 : 68.6~72.8, and in milled rice were 4.4~5.6 : 10.6~12.0 : 3.9~5.4 : 75.7~79.8. In albumin seven major bands were observed with molecular weights ranging from 14.g~96.8 kDa, in globulin four bands with molecular weights in the range of 14.4~56.9 kDa, prolamin had only one band with a molecular weight of 14.4 kDa, and glutelin had four bands with molecular weights of 14.4 ~ 57.4 kDa. There were no differences in electrophoretic patterns between rice varieties or between brown and milled rice.

• Journal of Microbiology and Biotechnology
• /
• 제17권2호
• /
• pp.313-319
• /
• 2007

The nutritional medium requirement for biosurfactant production by Bacillus licheniformis K51 was optimized. The important medium components, identified by the initial screening method of Plackett-Burman, were $H_3PO_4,\;CaCl_2,H_3BO_3$, and Na-EDTA. Box-Behnken response surface methodology was applied to further optimize biosurfactant production. The optimal concentrations for higher production of biosurfactants were (g/l): glucose, $1.1;NaNO_3,\;4.4;MgSO_4{\cdot}7H_2O,\;0.8;KCl,\;0.4;CaCl_2,\;0.27;H_3PO_4,\;1.0ml/l;\;and\;trace elements\;(mg/l):H_3BO_3,\;0.25;CuSO_4,\;0.6;MnSO_4,\;2.2;Na_{2}MoO_4,\;0.5;ZnSO_4,\;6.0;FeSO_4,\;8.0;CoCL_2,\;1.0;$ and Na-EDTA, 30.0. Using this statistical optimization method, the relative biosurfactant yield as critical micelle dilution (CMD) was increased from $10{\times}\;to\;105{\times}$, which is ten times higher than the non-optimized rich medium.

• 한국진공학회지
• /
• 제19권2호
• /
• pp.81-90
• /
• 2010

층과 층 사이의 정전기적인력, 수소결합 또는 공유결합을 이용하여 층당 두께를 수 옹스트롱에서부터 수십 나노미터까지 제조할 수 있으며 박막의 표면 형태를 흡착시키고자 하는 물질 및 박막 후처리 공정을 통해 제어할 수 있으며 더 나아가, 삽입하는 물질의 특성에 따라 박막의 기능성을 집적화 및 다양화시킬 수 있다. 본 연구에서는 이러한 층상자기조립방법의 특성을 이용하여 반사방지막, 초소수성 필름 및 전기화학센서로의 응용가능성을 제시하였다. 반사방지막의 경우, 구형의 블록공중합체를 유리기판 위에 다층박막으로 적층시킴으로써 박막 굴절률을 1.25까지 감소시켰고 이를 통해 약 99.5%의 빛 투과도를 달성할 수 있었다. 더 나아가 바이오물질인 엔자임을 다층박막에 삽입시킬 경우, 활성 산소를 분해시키는 전기화학센서로의 제조가 가능함을 보인다. 본 연구는 본인이 이미 발표한 논문(J. Am. Chem. Soc. 128, 9935 (2006); Adv. Mater. 19, 4364 (2007); Electro. Mater. Lett. 3, 163 (2007))들을 정리하여 층상자기조립법에 관해 소개하는 논문이다.

• Journal of Pharmaceutical Investigation
• /
• 제17권2호
• /
• pp.61-65
• /
• 1987

4-Pivaloyloxy, 4-benzenesulfonyloxy and 4-p-toluenesulfonyloxy compounds of piroxicam (2a, 2b and 2c) and isoxicam(4a, 4b and 4c) were synthesized in fairly good yield. Antiinflammatory and ulcerogenic effects of the 6 compounds were determined. Antiinflammatory effect of 2a was comparable to that of piroxicam and ulcerogenic effect of 2a was less than that of piroxicam.

• 대한화학회지
• /
• 제37권1호
• /
• pp.162-164
• /
• 1993

• Archives of Pharmacal Research
• /
• 제29권5호
• /
• pp.369-374
• /
• 2006

An efficient method for the synthesis of optically active 2-substituted 2,3-dihydro-4-quinolones has been developed. The key features include the introduction of a chiral side chain and the construction of quinolone skeleton by Mitsunobu alkylation and hydroarylation, respectively.

• Archives of Pharmacal Research
• /
• 제21권4호
• /
• pp.440-444
• /
• 1998

A series of 6-(N-arylamino)-7-methylthio-5,8-quinolinedione derivatives 4a-4l was newly synthesized for the evaluation of antifungal activity. 6-(N-Arylamino)-7-methylthio-5,8-quinolinediones were prepared by regioselective nucleophilic substitution of 6,7-dichloro-5,8-quinolinediones with arylamines in the presence of $Ce^{3+}$, and $Na_2$S/dimethylsulfate. The MIC values of 4a-4l were determined for antifungal susceptibility in vitro against Candida species by agar streak method. The derivatives 4a-4l had generally potent antifungal activities against all human pathogenic fungi. Especially they had the most potent activity against C. krusei at 12.5-0.8 $\mu\textrm{g}$/ml. Compounds 4d, 4g, 4h, 4j and 4k had more potent antifungal activities than fluconazole. Compounds 4g and 4h completely inhibited the fungal growth at 0.8-6.3 $\mu\textrm{g}$/ml against all Candida species, while fluconazole inhibited the growth at 25 $\mu\textrm{g}$/ml. The compounds such as 4g and 4h containing an N-(4-bromo-2-methylphenyl)- or N-(4-bromo-3methylphenyl)amino substituent exhibited the most potent antifungal activities.

• BMB Reports
• /
• 제31권1호
• /
• pp.83-88
• /
• 1998

Recently a B cell surface molecule, CD40, has emerged as a receptor mediating a co-stimulatory signal for B cell proliferation and differentiation. To investigate the mechanism of synergy between interleukin-4 (IL-4) and CD40 ligation in B cell activation, we have examined the effect of CE40 cross-linking on the IL-4 receptor expression in human B cells using anti-CE40 antibody. We observed that IL-4 and anti-CD40 both induce IL-4 receptor gene expression with a rapid kinetics resulting in a noticeable accumulation of IL-4 receptor mRNA within 4 h. While IL-4 caused a dose-dependent induction of surface IL-4 receptor expression, the inclusion of anti-CD40 in the IL-4-treated culture, further up-regulated the IL-4-induced IL-4 receptor expression as analyzed by flow cytometry. Pretreatment of B cells with inhibitors of protein tyrosine kinase (PTK) resulted in a significant inhibition of both the IL-4- and anti-CD40-induced IL-4 receptor mRNA levels, while protein kinase C (PKC) inhibitors had no effects. These results suggest that IL-4 and CD40 ligation generate B cell signals, which via PTK-dependent pathways, lead to the synergistic induction of IL-4 receptor gene expression. The rapid induction of IL-4 receptor gene expression through the tyrosine kinase-mediated signal transduction by B cell activating stimuli, would provide cells capacity for an efficient response to IL-4 in the early phase of IL-4 action, and may in part constitute the molecular basis of the reported anti-CD40 co-stimulatory effect on the IL-4-induced response.