• 한국환경과학회지
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• 제24권11호
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• pp.1541-1546
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• 2015

The objective of this research was to evaluate the toxicity of the industial xenobiotic Aroclor 1248 (A) and natural origin substances~elemental sulfur (S80) and oleic acid (OA) and their binary mixtures to V. fischeri bioluminescence during the prolonged exposure time (up to 60 min). The bioluminescence quenching test was used to determine the toxic effects. Full factorial experiment design and multiple regression analysis and the comparison of binary mixture effect with the sum of effects of individual chemicals were used for the evaluation of combined effects of toxicants. The analysis of general trend of mixture toxicity to bioluminescence showed that mixture toxic effects were reversible up to 60 min. Data analysis revealed different joint effects, which were depended on mixture composition. S80 enhanced toxic effect of A and acted additively with synergistic interaction. Hydrophobic OA in mixture with A acted antagonistically and in mixture with sulfur caused an additive effect with antagonistic component of interaction. It was concluded that low concentrations of natural toxic substances present in environmental samples as mixtures of chemicals can define the toxicodynamic character of industrial xenobiotics.

• Nuclear Engineering and Technology
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• 제43권5호
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• pp.421-428
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• 2011

The out-of-pile mechanical performance and microstructure of recrystallized Zr-1.5 Nb-S alloy was investigated. The strength of the recrystallized Zr-1.5Nb-O-S alloys was observed to increase with the addition of sulfur over a wide temperature range, from room temperature up to $300^{\circ}C$. A yield drop and stress serrations due to dynamic strain were observed at room temperature and $300^{\circ}C$. Wavy and curved dislocations and loosely knit tangles were observed after strained to 0.07 at room temperature, suggesting that cross slip is easier. At $300^{\circ}C$, however, dislocations were observed to be straight and aligned along the slip plane, suggesting that cross slip is rather difficult. At $300^{\circ}C$, oxygen atoms are likely to exert a drag force on moving dislocations, intensifying the dynamic strain aging effect. Oxygen atoms segregated at partial dislocations of a screw dislocation with the edge component may hinder the cross slip, resulting in the rather straight dislocations distributed on the major slip planes. Recrystallized Zr-Nb-S alloys exhibited ductile fracture surfaces, supporting the beneficial effect of sulfur in zirconium alloys. Oxidation resistance in air was also found to be improved with the addition of sulfur in Zr-1.5 Nb-O alloys.

• 천문학회보
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• 제38권1호
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• pp.49.1-49.1
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• 2013

We have been carrying out near-infrared (NIR) spectroscopy as well as [Fe II] narrow band imaging observations of Cassiopeia A supernova remnant (SNR). In this presentation, we describe the spectral classification of the iron knots around the SNR. From eight long-slit spectroscopic observations for the iron-bright shell, we identified a total of 61 iron knots making use of a clump-finding algorithm, and performed principal component analysis in an attempt to spectrally classify the iron knots. Three major components have emerged from the analysis; (1) Iron-rich, (2) Helium-rich, and (3) Sulfur-rich groups. The Helium-rich knots have low radial velocities (${\mid}v_r{\mid}$ < 100 km/s) and radiate strong He I and [Fe II] lines, that match well with Quasi-Stationary Flocculi (QSFs) of circumstellar medium, while the Sulfur-rich knots show strong lines of oxygen burning materials with large radial velocity up to +2000 km/s, which imply that they are supernova ejecta (i.e. Fast-Moving Knots). The Iron-rich knots have intermediate characteristics; large velocity with QSF-like spectra. We suggest that the Iron-rich knots are missing "pure" iron materials ejected from the inner most region of the progenitor and now encountering the reverse shock.

• 한국식품조리과학회지
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• 제1권1호
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• pp.33-39
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• 1985

생무우(태백무우, 알타리무우)에 존재하는 휘발성 함유황화합물을 수증기 증류 및 용매추출($CCl_4$)방법에 의해 추출하여 GC/MS 분석법에 의해 분리 확인하였다. 수증기 증류로 얻은 2종 무우의 휘발성 함유황 성분들의 GC profile은 유사하였으며, 4-methyl-pentyl, 3-methylthiopropyl, 4-methylthio-3-butenyl, 4-rnethylthiobutyl, 5-methylthiopentyl isothiocyanate 와 5-methylthio-4-pentenenitrile, 1-methylthio-3-pentanone, dimethyl sulfides 등이 분리 확인되었다. 한편 $CCl_4$추출물에는 4-methylsulfinyl-3-butenyl isothiocyanate도 존재하였다. 수증기 증류에서 는 4-methylthiobutyl isothiocyanate가, 그리고 $CCl_4$추출에서 는 4-methylthio-3-butenyl isothiocyanate가 각각 주된 휘발성 함유황 화합물이었다.

• Journal of Microbiology and Biotechnology
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• 제21권2호
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• pp.124-128
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• 2011

Ferredoxin is a typical iron-sulfur protein that is ubiquitous in biological redox systems. This study investigates the in vitro assembly of a [$Fe_2S_2$] cluster in the ferredoxin from Acidithiobacillus ferrooxidans in the presence of three scaffold proteins: IscA, IscS, and IscU. The spectra and MALDI-TOF MS results for the reconstituted ferredoxin confirm that the iron-sulfur cluster was correctly assembled in the protein. The inactivation of cysteine desulfurase by L-allylglycine completely blocked any [$Fe_2S_2$] cluster assembly in the ferredoxin in E. coli, confirming that cysteine desulfurase is an essential component for iron-sulfur cluster assembly. The present results also provide strong evidence that [$Fe_2S_2$] cluster assembly in ferredoxin follows the AUS pathway.

• 농약과학회지
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• 제18권4호
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• pp.376-382
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• 2014

황토유황합제 제조 5주 후 녹지 않은 잔재물을 제외하고 수용성 황토유황합제만 준비하였다. 황토유황합제 제조시 가성소당를 원래 양보다 25% 감량하여 황토유황합제의 pH를 pH 1 낮추었다. 현미식초(pH 2.8)을 이용하여 황토유황합제의 pH 수준을 pH 5.0에서11.0까지 현미식초(pH 2.8)를 이용하여 pH를 1씩 조절하였다. 황토유황합제 원액의 pH는 13으로 토마토에 살포하였을 때 신초와 꽃눈에 약해를 주었다. pH가 조정된 0.05% 황토유황합제를 E. cichoracearum에 의해 흰가루병이 발생한 토마토에 7일간격으로 2회 살포하였다. pH가 조정된 황토유황합제를 1회 살포하고 7일 후 토마토의 흰가루병이 70~95% 방제되었다. 두 번째 살포 후 토마토 흰가루병이 확연하게 방제되었다. 결론적으로 pH를 조정한 황토유황합제는 토마토에 약해를 보이지 않으며, 유기농업에서 토마토 흰가루병 방제용 자재로 사용할 수 있을 것으로 생각한다.

• 대한소아치과학회지
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• 제30권1호
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• pp.33-40
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• 2003

구취를 일으키는 구강 내 혐기성 세균 일종인 Fusobacterium nucleatum은 유황 성분이 함유된 배지에서 $H_2S$와 같은 휘발성 유황화합물을 생성하고 철 성분과 결합하면 FeS를 형성한다. 구강내 여러 인자에 의하여 Fusobacterium nucleatum에 의하여 생성되는 유황화합물 농도가 달라진다. 본 연구에서는 Fusobacterium nucleatum의 유황화합물 생성시 영양 물질과 pH의 영향을 연구하여 다음과 같은 결과를 얻었다. 1. 배지에 sodium thiosulfate가 1.0% 되도록 첨가하면 배지의 흡광도는 $0.817{\pm}0.032$로, L-cysteine hydrochloride를 0.05% 되도록 첨가하면 $1.297{\pm}0.024$가 되었다. 2. 배지에 자일리톨을 첨가하면 배지의 흡광도는 $0.799{\pm}0.032$인데 반하여 포도당과 병합으로 첨가하면 $1.775{\pm}0.003$으로, 과당과 병합으로 첨가하면 $1.648{\pm}0.022$로 증가하였다. 3. 배지의 pH가 5.5 이상이면 휘발성 유황화합물 농도는 20,000 ppb이상이었다. 배지의 흡광도는 배지 내 L-cysteine hydrochloride 농도가 높을수록 높았으며, 배지의 pH가 산성으로 갈수록 낮았다. 4. 배지 위에 증류수나 식염수가 있을 때, 그리고 그 양이 적을수록 휘발성 유황화합물 농도는 높았다. 이상의 결과를 종합하면 Fusobacterium nucleatum에 의한 유황화합물 생성 이 자일리톨과 산에 의하여 억제되었다.

• 한국대기환경학회지
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• 제9권4호
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• pp.278-287
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• 1993

In order to calssify smog type durnig the summer season in Seoul, air Quality and meterorological data were analyzed by multivariate analysis. Among 15 variables relating to visibility, 10 variables were selected by multiple regression analysis for clustering of smog types; total suspended particle, sulfur dioxide, ozone, ntrogen dioxide, total hydrocarbon, south-north wind component, ralative humidity, precipitable water, mixing height and air temperature. Somg types were grouped into three clusters using cubic clustering criterion and the mumbers of days in each cluster were contained 74, 28 and 16 days. Each cluster was seperated clearly by sulfur dioxide, precipitable water and air teperature. The first cluster was representative of high ozone concentration and prevailing meterological conditions for ozone formation. Therefore, visibility in the first cluster was considered to be affected by photochemical smog. The third cluster showed characteristics of sulphurous smog type due to the higher concentration of primary pollutant, based on the dry condition than that in another cluster. On the other hand, the characteristic of the second cluster was not relatively clear, but considered to be in an intermediate characteristic between photochemical smog and sulphurous smog type.

• Archives of Pharmacal Research
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• 제28권4호
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• pp.391-394
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• 2005

The allylthio group of allicin and other organosulfur compounds, isolated from garlic, is considered a pharmacophore, and a key structure component of the molecule, which affords biological activities. In the foregoing studies, various 3-alkoxy-6-allylthiopyridazine derivatives (K­compounds) were synthesized, and their biological activities tested in animals. As expected, the various derivatives showed good hepatoprotective activities on carbon tetrachloride-treated mice and aflatoxin B1-treated rats, and chemopreventive activities on hepatocarcinoma cells in rats. Other new pyridazine derivatives, with the oxygen atom at the 3-position of the 3-alkoxy­6-allylthiopyridazine displaced by sulfur (S), were synthesized, and their activities tested in vitro. Thio-K6, one of the sulfur-substituted compounds, showed better chemopreventive activity toward hepatocarcinoma cells.

• 한국식품조리과학회지
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• 제17권1호
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• pp.55-59
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• 2001

신선 및 동결 건조된 두메부추 잎을 연속수증기 증류추출 장치로 증류하여 얻어진 정유성분을 GC 및 GC-MS로 분석하여 신선한 시료에서 11종의 hydrocarbons 0.136ppm 9종의 aldehydes 0.278ppm, 4종의 alcohols 0.025ppm, 2종의 esters 2.328ppm, 7종의 acids 0.545ppm, 4종의 ketones 0.037ppm 및 9종의 sulfur containing compounds 0.117ppm의 총 46종의 성분을 확인하였다. 동결 건조한 두메부추 잎에서는 8종의 hydrocarbons 1.357ppm 5종의 aldehydes 0.498ppm, 3종의 alcohols 0.094ppm, 5종의 esters 0.720ppm, 2종의 acids 0.069ppm 3종의 ketones 0.163ppm 및 4종의 sulfur containing compounds 0.039ppm을 포함하여 총 30종의 향기성분이 확인되었다. 전자코의 분석 결과, 제1주성분 값의 기여율이 0.987을 나타내어 제1주성분이 두메부추와 부추를 총괄하는 정보로 사용될 수 있음을 알 수 있다. 신선한 두메부추는 제1주성분 값이 0.5부근에 집중된 분포를 보이고, 신선한 부추는 -0.5부근에 분포되어 있어 신선한 두메부추와 신선한 부추의 휘발성 향기성분 패턴이 다름을 알 수 있었다. 또한 동결 건조된 시료의 경우, 두메부추는 제1주성분 값 0을 중심으로 -쪽에 분포되어 있고, 부추는 +부근에 분포되어 있어 동결 건조된 시료의 휘발성 향기성분 패턴도 차이가 있었다.