• 한국식품영양과학회지
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• 제23권3호
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• pp.466-471
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• 1994

The antioxidant activity of methanol extracts of thirty plants was tested using the methol of 1, 1-diphenyl-2-pi-cryl hydrazyl (DPPH) reactivity. Four methanol extracts from Zingiber officinale, Piper nigrum , Zanthoxylum schinifolium and Capsocum annuum were found to be the most effective on DPPH radical scavenging activity. The next effective ones were Perilla frutescens , Sedium sarmentosum , Raphnus sativas, aArctium lappa, Beta vulgaris. Brassica oleracea var. Acephala, bBrassica juncea inorder, and the others did not show a considerable activity. The methanol extract obtained from the seed coats of Zanthoxylum schinifolium was fractinated with several sovlents. The interphase materials exhibited the strongest antioxidant activity and was further purified by silica gel and Sephadex LH-20 column chormatography. Two active principles were isolated and identified as quercetin -3-O-$\alpha$-L-rhamonopyranoiside(quercitrin) and quercetin 3-O-$\alpha$-D-galactopyranoside (hyperoside) by ultraviolet(UV), proton nuclear magetic resonance (1H-NMR) and carbon nuclear magnetic resonance (13C-NMR). Its antioxidative activity was a little higher that that of L-ascorbic acid.

• 한국수소및신에너지학회논문집
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• 제28권2호
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• pp.144-149
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• 2017

A proton-conducting bisphenylpropaned sulfonated fluorinated blockcopolymer (BPSFBC) was synthesized. Five kinds of polymer electrolyted composite membranes were preparated by incorporating silica ($SiO_2$) with various weight ratio. And their characteristics were investigated by FT-IR (fourier transform infrared), $^1H-NMR$ ($^1H$ nuclear magnetic resonance), TGA (thermogravimetric analysis), water uptake, FE-SEM (field emission scanning electron microscopes), and ion conductivity properties. The water uptake and ion conductivity were increased until 9 wt% $SiO_2$, and then decreased. The maximum proton conductivity equal to $52mScm^{-1}$ was measured for the BPSFBC/$SiO_2$-9 composite membrane at $90^{\circ}C$ and 100% relative humidity. From the measured results, it is distinct that the manufactured composite membrane BPSFBC/$SiO_2$-9 can be considered as a polymer membrane suitable for a fuel cell electrolyte.

• 한국균학회지
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• 제16권1호
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• pp.9-15
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• 1988

H. sativum 배양액에서 두가지 종류의 식물독소물질이 검출되었으며, 이들을 M-toxin과 D-toxin으로 명명하였다. Lettuce 식물반응결과는 D-toxin 보다 뿌리성장의 저해작용이 적었다. 화학분석결과 M-toxin은 특별히 작은 peptid로 되어 있었다. D-toxin는 Helrninthosporal와 화학적 성질이 비슷하였으나 같지는 않았다. 이는 UV, proton NMR와 질량분석기의 기본 자료인 결과이며, D-toxin은 적어도 두개의 isomers로 되어 있었다.

• 한국자동차공학회논문집
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• 제11권1호
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• pp.64-71
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• 2003

In order to analyze the effect of the chemical structure and the cetane number of reformed diesel fuels by ultrasonic energy irradiation, proton nuclear magnetic resonance spectrometer$(^1H-NMR)$ was used. From the study, following conclusive remarks can be made. 1) Branch Index(BI), aromatics percentages, and alpha methyl radical$(H_{\alpha})$ of the reformed diesel fuels by ultrasonic energy irradiation decreased more than the conventional ones. 2) All the cetane numbers which were calculated from carbon type structure and hydrogen type distribution of the reformed diesel fuels increased more than the conventional ones. 3) It is more reasonable to predict cetane number equation from carbon type structure than from hydrogen type distribution. 4) BI, aromatics percentages, and $H_{\alpha}$ on both for conventional fuel and reformed diesel fuels by ultrasonic energy irradiation are inversely proportional to cetane number fur these fuels.

• 한국고분자학회:학술대회논문집
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• 한국고분자학회 2006년도 IUPAC International Symposium on Advanced Polymers for Emerging Technologies
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• pp.260-260
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• 2006

Sericin was modified by solution blending (10-30 wt%) with 70-90 wt% polyacrylamide (PAM) in water. The reactive sites of sericin such as serine and tyrosine were attached to PAM. Proton Nuclear Magnetic Resonance ($^{1}H-NMR$) and thermogravimetric analysis were used to characterize the modified sericin. The electrospinning conditions i.e. the blend composition and the power supply voltage, at a tip to target distance of 15 cm were studied. The morphology of nanoparticles and nanofibers was observed by scanning electron microscopy. The average particles size of the nanoparticle obtained was 191 nm and nanofibers was 150-300 nm.

• Bulletin of the Korean Chemical Society
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• 제24권3호
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• pp.339-344
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• 2003

The conformation of synthetic oligosaccharide can be elucidated by employing molecular modeling and highfield proton NMR (nuclear magnetic resonance) spectroscopy. Information with respect to the composition and configuration of saccharide residues and the sequence and linkage positions of the oligosaccharide can be obtained by employing a variety of one- and two-dimensional NMR techniques and molecular modeling. These techniques are also useful in establishing the solution conformation of the oligosaccharide moiety. This study is focused on the elucidation of linkage positions of synthetic trisaccharides, Gal(β1-4)Glc(β1-3)Glc, Gal(β1-4)Glc(β1-4)Glc and Gal(β1-4)Glc(β1-6)Glc.

• Bulletin of the Korean Chemical Society
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• 제30권7호
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• pp.1559-1562
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• 2009

The influence of hot pressing on the pore structures of Nafion membranes was investigated by observing the Nafion before and after hot pressing with $^1H$ nuclear magnetic resonance (NMR) spectroscopy. The freezing point depression and chemical shift data of water in the Nafion indicated the presence of two different pore size ranges in Nafion. Hot pressing mainly reduced the sizes and number of the big pores. The reduction of water uptake and proton conductivity after hot pressing was explained by this variation of pore size and number. We demonstrated the potential application of chemical shift data and NMR cryoporometry experiments to measure the relative pore sizes, on a nano scale, and numbers.

• 대한환경공학회지
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• 제27권1호
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• pp.11-16
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• 2005

한강을 상수원으로 하는 재래식 정수처리 시설의 각 단위공정으로부터 휴믹물질(HS; humic substances)을 분리하여 작용기 분포, 화학적 조성, FT-IR(Fourier transform infrared) 그리고 $^1H-NMR$(proton nuclear magnetic resonance) 스팩트럼을 분석하여 구조 및 화학적 특성을 평가하였다. HS의 농도분포는 정수처리 동안 47.2%에서 26.4%(0.97 mgC/L에서 0.54 mgC/L)로 단계적으로 감소하였다. HS 중 페놀기(phenolic groups)의 농도분포는 정수처리 동안 60.5%에서 21.8%($12.2{\sim}6.0\;{\mu}M/L$ as phenolic-OH)로 점차 감소하였으며, 카르복실기(carboxylic groups)의 경우 전염소처리 이후 39.5%($7.9\;{\mu}M/L$ as COOH)에서 46.9%($10.6\;{\mu}M/L$ as COOH)로 증가하였지만 응집 침전 그리고 모래여과 이후 34.2%($9.4\;{\mu}M/L$ as COOH)까지 단계적으로 감소하였다. 또한 원소분석과 FT-IR 및 $^1H-NMR$ 분석결과 정수처리 공정을 거치면서 카르복실기의 분율이 증가하고 방향족에 대한 지방족 양성자의 비($P_{Al}/P_{Ar}$)가 증가하는 것으로 조사되어 상대적으로 지방족 화합물의 물질분율이 증가하는 것을 확인하였다.

• 한국식품과학회지
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• 제36권4호
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• pp.643-647
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• 2004

땅콩껍질에 함유된 항미생물 활성물질의 탐색을 위해 땅콩껍질을 MeOH로 추출하고 이 MeOH 추출물을 용매분획하여 EtOAc 중성획분을 얻었다. 이 획분에 함유된 항미생물 활성물질을 silica gel adsorption column chromatography, Sephadex LH-20 column chromatography, ODS column chromatography로 정제한 다음 HPLC를 이용하여 1종의 화합물을 단리하였다. $^1H-NMR$, MS 및 NOESY 분석에 의해 땅콩껍질로부터 분리된 항미생물 활성물질은 pratensein으로 동정되었다.

• 대한화학회지
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• 제19권4호
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• pp.233-239
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• 1975

세개의 二重結合에 衣하여 conjugate된 비대칭화합물 cis-2-bitenedialdioxime의 두 oxime group의 configuration을 溶媒, 溫度 및 濃度의 影響에 대한 NMR 硏究로서 決定하였다. 溶液狀態에서의 이 化合物은 $-35^{circ}$∼$-95^{\circ}C$의 溫度條件下에서는 항상 "syn-syn" configuration으로 存在함을 알았다. 또한 이 化合物의 oxime group과 溶媒사이의 水素結合의 相對的强度와 溫度 및 濃度에 의 피리딘의 考察하고 몇가지 水素結合의 모델을 提示하였다. 特히 피리딘溶媒 속에서는 水素結合은 한 영향을 窒素가 갖고 있는 非共有電子雙에 衣해서 일어나지 않고, oxime 의 hydroxyl proton과 피리딘의 $\pi$軌道函數 사이에 形成되는 $\pi$-착물의 結果임을 알았다.