• 한국산학기술학회논문지
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• 제11권1호
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• pp.228-233
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• 2010

Methyl hydrogen polysiloxne으로 처리한 ZnO, fumed $SiO_2$와 다양한 망간 전구체를 이용하여 서브마이크로미터 크기를 갖는 망간이 도핑된 $Zn_2SiO_4$ 형광체 입자를 고상법으로 제조하였다. 결정화와 광발광 특성은 XRD, SEM, PL스펙트라를 이용하여 분석하였다. 고상법으로 제조한 망간 도핑된 $Zn_2SiO_4$는 methyl hydrogen polysiloxne 처리한 ZnO의 분산과 응집 때문에 $1000^{\circ}C$에서 성공적으로 얻어졌고, 진공자외선 여기하에서 제조된 입자의 최대 PL강도는 0.02mol Mn, $1000^{\circ}C$에서 확인되었다.

• 한국세라믹학회지
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• 제51권3호
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• pp.139-144
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• 2014

Activated carbon fiber (ACF) was modified with MnS nanoparticles to prepare MnS-ACF, and it was employed for preparation of MnS-$ACF/TiO_2$ composites with titanium (IV) n-butoxide (TNB). The properties of MnS-$ACF/TiO_2$ composites were characterized by XRD, SEM, and EDX. EDX results showed the presence of C, O, and Ti as major elements and traces of the metal elements Mn and S. The photocatlytic activity was evaluated by degradation of methyl blue (MB) and methyl orange (MO) dye. The results demonstrated that as-prepared samples could effectively photodegrade MB and MO under UV irradiation. Subsequently, the decomposition of MB solution showed the combined effects of adsorptions by ACF and enhanced photocatalytic effect by $TiO_2$. Finally, the photocatalytic effect increased due to photo-induced-electron absorption effect by ACF and electron trap effect by comodified MnS nanoparticles.

• Archives of Pharmacal Research
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• 제14권2호
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• pp.143-146
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• 1991

A new synthetic sequence for the chiral lactone moiety of compactin was developed from $\alpha$-D-glucose in 9 steps via simultaneous reductive detosylation and epoxide-ring opening of 2, 3-epoxy-4-tosylate using NaBH_4$ to afford 2, 4-dideoxy sugar as a key intermediate.

• Bulletin of the Korean Chemical Society
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• 제22권8호
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• pp.842-846
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• 2001

Solvolyses of N-methyl-N-phenylcarbamoyl chlorides in aqueous binary mixtures of acetone, ethanol, methanol and in water, D2O, and 50% D2O-CH3OD are investigated at 25.0 $^{\circ}C.$ The Grunwald-Winstein plots of first-ord er rate constants for N-methyl-N-phenylcarbamoyl chlorides with YCl (based on 2-adamantyl chloride) show a dispersion phenomenon. The ring parameter (I) has been shown to give considerable improvement when it is added as an hI term to the original Grunwald-Winstein and extended Grunwald-Winstein correlations for the solvolyses of N-methyl-N-phenylcarbamoyl chlorides. This study has shown that the magnitude of l, m and h values associated with a change of solvent composition is able to predict the dissociative SN2 transition state. The kinetic solvent isotope effects determined in deuterated water are consistent with the proposed mechanism of the general base catalyzed and/or a dissociative SN2 mechanism channel for N-methyl-N-phenylcarbamoyl chlorides solvolyses.

• Journal of the Korean Wood Science and Technology
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• 제45권3호
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• pp.250-257
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• 2017

계수나무 잎, 목질부 및 수피부의 EtOAc 및 물 분획으로부터 gallic acid (1), methyl gallate (2), kurigalin (3), 1,2,3,6-tetra-O-galloyl-${\beta}$-D-(+)-glucose (4), 1,2,3,4,6-penta-O-galloyl-${\beta}$-D-(+)-glucose (5), 6-m-digalloyl-1,2,3,4,6-penta-O-galloyl-${\beta}$-D-(+)-glucose (6), isocorilagin (7), macabarterin (8) 등 8종류의 가수분해형 탄닌을 단리하였으며, 각 화합물에 대한 항산화 활성 및 항염활성 시험을 실시하였다. 항산화 활성은 DPPH 라디칼 소거법을 사용하였으며, 단리된 화합물 모두 대조군으로 사용된 BHT 및 ${\alpha}$-tocopherol에 비하여 매우 우수한 항산화 활성을 나타냈다. 항염활성 시험 결과 methyl gallate, 1,2,3,6-tetra-O-galloyl-${\beta}$-D-glucose 그리고 1,2,3,4,6-penta-O-galloyl-${\beta}$-D-glucose가 NO생성을 억제하였으며, 특히 methyl gallate가 가장 높은 NO 생성 억제효과를 가지는 것으로 나타났으나 항염제로 이용될 수 있는 효능을 가지고 있지는 않았다. 이와 같은 결과를 토대로 계수나무의 가수분해형 탄닌 화합물은 항염제보다 합성 항산화제를 대체할 수 있는 천연 항산화 소재로써의 적용 가능성을 나타내었다.

• 한국잡초학회지
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• 제14권1호
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• pp.28-33
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• 1994

본(本) 실헌(實驗)은 pyributicarb/bensulfuron-methyl과 oxadiazon/bensulfuron-methyl 액상수화제(液狀水和劑)의 제초효과(除草效果)를 검토(檢討)하고 사용(使用) 기술(技術) 개발(開發)을 자연(目的)으로 수행(遂行)하였다. 1. Pyributicarb/bensulfuron-methyl과 oxadiazon/bensulfuron-methyl 액상수화제(液狀水和劑)의 제초효과(除草效果)는 입제(粒劑)와 유사(類似)하였다. 2. Pyributicarb/bensulfuron-methyl과 oxadiazon/bensulfuron-methyl 액상수화제(液狀水和劑)의 확산(擴散) 거잡(距雜)는 6m 이상(以上)이었다. 3. Pyributicarb/bensulfuron-methyl 액상수화제(波狀水和劑)를 관수시(灌水時) 물꼬처리(處理)와 담수(湛水) 후(後) 논뚝처리(處理)한 후(後) 제초효과(除草效果)는 90% 이상(以上)이었다. 4. Pyributicarb/bensulfuron-methyl 액상수화제(波狀水和劑)의 침강속도(沈降速度)는 1시간(時間)에 1-2cm 정도(程度)였다. 5. Pyributicarb/bensulfuron-methyl 액상수화제(波狀水和劑)의 담수심별(湛水深別) 제초효과(除草效果)는 담수심(湛水深) 0-1cm에서 보다 6-7cm에서 더 높았다.

• 대한화학회지
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• 제51권1호
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• pp.31-35
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• 2007

트리포달 구리(II) 착물 [Cu(pmea)(H2O)](ClO4)2·H2O (1) (pmea=bis[(2-pyridyl)methyl]-2-(2-pyridyl)-ethylamine)을 합성하고 X-선 회절법으로 구조를 규명하였다. 이 착물은 삼사정계, 공간군 P-1, a = 9.9362(9) A, b = 15.7299(17) A, c = 18.0562(11) A, α = 68.760(8)°, β = 76.331(6)°, γ = 77.092(9)°, V = 2526.2(4) A3, Z = 2로 결정화 되었다. 각각의 구리 원자는 약간 일그러진 사각뿔 구조를 갖는데, 바탕 면은 pmea 리간드에 있는 세 개의 질소원자와 물 분자가 포함되어 있으며 축 방향에는 피리딘 고리의 질소 원자가 포함되어있다. 착물 1의 순환 전압전류 그림은 가역 일-전자 산화 CuIII 및 환원 CuI 과정으로 진행됨을 보여주었다.

• 생약학회지
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• 제30권4호
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• pp.420-422
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• 1999

From the EtOAc fraction of Dipsacus asper, four compounds have been isolated. On the basis of spectral data, these compounds were identified as protocatechuic acid, caffeic acid, 3,4-di-O-caffeoyl quinic acid and methyl 3,4-di-O-caffeoyl quinate.

• Bulletin of the Korean Chemical Society
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• 제26권4호
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• pp.609-613
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• 2005

The fragmentation patterns and ion-molecule reactions of two alkyn alcohols, 2-propyn-1-ol (HC≡$CCH_2$OH) and 2-methyl-3-butyn-2-ol (HC≡CC($CH_3)_2$OH), were investigated using Fourier transform mass spectrometry (FTMS). The most abundant fragment ions formed from the molecular ions were [M-H]$^+$ for 2-propyn-1-ol and [M-$CH_3]^+$ for 2-methyl-3-butyn-2-ol. The dehydrated ion, [M-$H_2O]^+$ was formed only from 2-propyn-1-ol in which $\alpha$ -hydrogen atoms were available for $\alpha,\;\alpha$ -elimination reaction. The protonated molecules were dissociated into [M+H-$H_2O]^+$ and [M+H-$C_2H_2]^+$ through dehydration and deacetylenylation processes. The formations of [M+H-$H_2O]^+$ and [M+H-$C_2H_2]^+$ from 2-methyl-3-butyn-2-ol were more favorable than those from 2-propyn-1-ol due to stabilization by two methyl groups at $\alpha$ -carbon. Ion-neutral complexes formed at long ion trapping time gave dehydrated and/or deacetylenylated ion products by further dissociation.

• Food Science and Biotechnology
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• 제14권3호
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• pp.392-398
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• 2005

Fresh, and sun- and oven-dried red peppers were analyzed for volatile components. Also, their odor-active compounds were determined using gas chromatography-olfactometry (GC-O). More diverse volatile components, such as aldehydes, ketones, acids, and esters, were found in dried samples than in fresh ones. They included hexanal, ethyl acetate, ${\alpha}$-ionone, and ${\beta}$-ionone. Some Strecker aldehydes, 2-methyl butanal and 3-methyl butanal, were found only in dried red peppers. More hydrocarbons of high volatility and terpene-type components, such as ${\gamma}$-terpinene and aromadendrene, were detected only in fresh red peppers. A considerable amount of naphthalene was formed during sun-drying, whereas 2-furancarboxaldehyde, 1-methyl-1H-pyrrole and benzeneethanol were detected only in oven-dried red peppers. Characteristic odor of fresh ones could be attributed to 3-penten-2-o1, 2-methyl-2-butenal, 2-methoxy phenol, 2-hydroxy-methyl-benzoate, and 2-phenoxy ethanol, whereas some odorants, including 2-pentyl furan, naphthalene, hexyl hexanoate, and ${\alpha}$-ionone, could be responsible for distinctive odor property of sun-dried red peppers. 2-Furancarboxaldehyde, benzeneethanol, 4-vinyl-2-methoxy phenol, and unknown played important roles in odor property of oven-dried red peppers.