• KSBB Journal
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• 제17권4호
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• pp.345-349
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• 2002

항균성 물질이 함유된 투명한 신기능 포장필름의 제조를 위하여 흡착제로서 수용성 silica를 선택하여 항균성 물질의 흡착 및 내열성을 조사하였다. Methanol 자화 방선균 (MO-16, MO-17)이 생산하는 천연 항균성 물질을 ethylacetate로 추출, 농축하여 silica에 흡착시킨 후 열처리한 결과 15$0^{\circ}C$에서 5분까지 항균효과가 유지되었다. 따라서 투명필름의 제조시에 흡착제로서 silica의 첨가가 효과적이라고 판단되었다. 항균제인 benzoic acid(BA) 는 세균 및 곰팡이에 강한 항균효과를 나타내었으며, 특히 곰팡이에 대한 항균력이 우수하였고, 10$0^{\circ}C$, 5분간 열처리시에도 항균력을 유지하였다. 또한 항균성 물질과 공동 첨가시 약간의 상승효과를 나타내어 필름 제조시 공동 첨가하므로서 첨가량의 감소에 따른 비용의 절감 및 항진균 효과가 보완된 필름제조가 가능하다고 사료되었다.

• Bulletin of the Korean Chemical Society
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• 제20권8호
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• pp.893-896
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• 1999

Novel citric acid based Ti, Nb and Ta precursors that are highly stable in the presence of water were developed. No alkoxides of Ti, Nb and Ta were utilized in the preparation, instead much less moisture-sensitive metallic Ti, NbCl5 and TaCl5 were chosen as starting chemicals for Ti, Nb and Ta, respectively. The feasibility of these chemicals as precursors is demonstrated in the powder synthesis of BaTi4O9, Y3NbO7 and LiTaO3. The water-resistant Ti precursor was employed as a new source of water-soluble Ti in the amorphous citrate method, and phase pure BaTi4O9 in powdered form was successfully synthesized at 800 ？. The Pechini-type polymerizable complex method using the water-resistant Nb and Ta precursors was applied to the synthesis of Y3NbO7 and LiTaO3, and both the powder materials in their pure form were successfully synthesized at reduced tempera-tures, viz. 500-700 ？. The remarkable retardation of hydrolysis of these water-resistant precursors is explained in terms of the partial charge model theory.

• 한국식품영양과학회지
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• 제27권2호
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• pp.275-280
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• 1998

The possibility of utilizing Porphyra yezoensis, Undaria pinnatifida and Laminaria religionsa into algae-tea having biological functionality was investigated by analysis of functional component, experimentation for low viscosity and various pretreatments. In water soluble fraction of powdered algae extracted for 3 minutes with 30 times of hot wate, major functinal components were composed of 1.53% porphyran and 170.04mg% taurine in P. yezoensis, 1.09% fucoidan and 1.18% sodium sodium alginate in U. pinnatifida, and 1.28% fucoidan, 1.99% soidum laginate and 371.25mg% iodine in L.religiosa, on dry basis. For lowering viscosity and masking off-flavor in each water soluble fraction, it was desirable that P. yezoensis was washed for 12 hours in sea water and 30 mimutes in fresh water, dried at 3 to 5$^{\circ}C$, powdered to size of 30 mesh nd then roasted for 3 minutes at 12$0^{\circ}C$, and that both U. pinnatifida and L. religiosa were washed, semidried to 40~50% moisture content, heated for 40 minutes at 12$0^{\circ}C$ by autoclave, dried, powdered to size of 30 mesh and then roasted for 5 minutes at 11$0^{\circ}C$.

• 한국환경보건학회지
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• 제29권3호
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• pp.91-96
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• 2003

This study was intended as an investigation of characteristics of background site atmospheric respirable particulate matters(RPM), and fine particles(<2.5 ${\mu}{\textrm}{m}$). The particle size distributions during the phenomenon of Yellow Sand(YS) occurs from April, 2001. Atmospheric aerosol particulate matter was directly collected on the Jeju island between 1 to 30, April, 2001 using an eight-stage cascade impacter(particle size range: 0.43-11 ${\mu}{\textrm}{m}$), and cyclone separator(cut size: 2.5, 10 ${\mu}{\textrm}{m}$). The episode of YS observed in background monitoring site, Kosan and appeared 2 times at sampling period. The mass concentrations of fine and coarse particles for YS episode were 34.2 and 59.6 $\mu\textrm{g}$/㎥, respectively, which were significantly increased amounts compared to 13.3 and 13.0 $\mu\textrm{g}$/㎥ for NonYS(NYS). Most size distributions had two peaks, one at 0.43∼.65 ${\mu}{\textrm}{m}$ and the other at 3.3${\mu}{\textrm}{m}$4.7 ${\mu}{\textrm}{m}$. The result of analysis of water-soluble ion component indicated that sulfate was mainly ion component, but nitrate and calcium ion was significantly increased at the YS episode.

• Toxicological Research
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• 제12권1호
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• pp.41-46
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• 1996

This study was performed to investigate the antitoxic component in methanol fraction of Lonicerae fios. The results were as follows: 1. When a 500 ppm of water soluble fraction of Lonicerae flos was administered, it showed the highest antitoxic effect. 2. Generally, detoxication effects by methanol fraction of Lonicerae fios increased. When the ethyl acetate soluble fraction of Lonicerae rios was administered, it exhibited the highest antitoxic effect against the toxicity of cadmium in Liver. 3. The combined administration of cadmium and methanol fraction of Lonicerae rios significantly increased metallothionein in liver compared to administration of cadmium only. This phenomenon was more remarkable when the ethyl acetate soluble fraction of Lonicerae fios was administered with cadmium chloride.

• 폴리머
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• 제31권5호
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• pp.374-378
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• 2007

Acrylamide(AM), diacetone acrylamide(DAAM) 및 acrylic acid(AAc)를 사용하여 수용성 삼원공중합체를 제조하고, 4-azidoaniline을 반응하여 azido기를 고분자 곁사슬에 도입한 일성분계 포토레지스트를 제조하였다. AM을 주성분으로 하고 DAAM을 공단량체로 사용한 공중합체를 합성하구 광가교제로 4,4'-diazidostilbene 2,2'-disulfuric acid sodium salt(DAS)를 혼합한 이성분계 포토레지스트를 제조하여 두 종류 포토레지스트의 감광특성을 비교하였다. 포토레지스트의 azido기 1 mol에 대한 감광특성은 고분자 곁사슬에 azido기를 가진 일성분계의 경우가 bis-azido기를 가진 이성분계보다 약 4배정도 우수한 감광성을 나타내었다. 직경 $110{\mu}m$ 크기의 원형패턴을 낮은 광세기에서 일성분계 포토레지스트를 사용하여 얻었으며, 노광부와 비노광부 계면에 잔존물이 없이 원형 패턴이 형성되어 블랙 매트릭스용 negative 포토레지스트로 활용이 기대된다.

• 약학회지
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• 제13권2_3호
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• pp.71-75
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• 1969

Chemical changes in components of ginseng roots by heat treatment were observed. We have let the roots of fresh ginseng, of steamed ginseng and the water soluble parts obtained from preparing steamed one be subject to our research. Acids, bases, neutral substances and genins from each one of the above came up to 12 fractions. Having the fractions through column chromatography and TLC test thereafter, we determined the Rf values of each spots presented. Among so many similar values of them, 15 spots of heterogenous component in the fresh ginseng and 6 spots in the steamed one, and 10 spots in that of water soluble parts wre detected. Considering this data obtained, we can assume that partialor all of some components of fresh ginseng might be passed into water parts while preparing steamed ginseng from fresh ones and also some components of the later (fresh ginseng) might have been converted into other substances while being heated.

• 한국대기환경학회지
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• 제30권1호
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• pp.1-17
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• 2014

Temporal variations of optical properties of urban aerosol in Seoul were estimated by the Optical Properties of Aerosols and Clouds (OPAC) model, based on hourly aerosol sampling data in Seoul during the year of 2010. These optical properties were then used to calculate direct radiative forcing during the study period. The optical properties and direct radiative forcing of aerosol were calculated separately for four chemical components such as water-soluble, insoluble, black carbon (BC), and sea-salt aerosols. Overall, the coefficients of absorption, scattering, and extinction, as well as aerosol optical depth (AOD) for water-soluble component predominated over three other aerosol components, except for the absorption coefficient of BC. In the urban environment (Seoul), the contribution of AOD (0.10~0.12) for the sum of OC and BC to total AODs ranged from 23% (spring) to 31% (winter). The diurnal variation of AOD for each component was high in the morning and low in the late afternoon during the most of seasons, but the high AODs at 14:00 and 15:00 LST in summer and fall, respectively. The direct negative radiative forcing of most chemical components (especially, $NO_3{^-}$ of water-soluble) was highest in January and lowest in September. Conversely, the positive radiative forcing of BC was highest in November and lowest in August due to the distribution pattern of BC concentration.

• 한국환경과학회지
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• 제26권4호
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• pp.447-456
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• 2017

Chemical properties of aerosols were investigated by analyzing the inorganic water-soluble content in $PM_{2.5}$ collected in the downtown area of Jeju City in Jeju Island. Due to an increase in both the number of visiting tourists and the size of local population, the number of cars in this area is increasing, causing an increase in $PM_{2.5}$. Eight $PM_{2.5}$-bound major inorganic ions were analyzed during the summer and winter periods. The water-soluble inorganic component represents a significant fraction of $PM_{2.5}$. In particular, secondary inorganic aerosols contribute 36.2% and 47.5% of $PM_{2.5}$ mass in summer and winter, respectively. Nitrate concentrations increase for $[NH_4{^+}]/[SO_4{^{2-}}]$>1.5, and excess ammonium, which is necessary for ammonium nitrate formation, is linearly correlated with nitrate. These results are clearly observed during the winter because conditions are more conducive to the formation of ammonium nitrate. A significant negative correlation between Nitrogen Oxidation Ratio (NOR) and temperature was observed. The obtained results can be useful for a better understanding of the aerosol dynamics in the downtown area in Jeju City.

• Natural Product Sciences
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• 제20권1호
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• pp.33-38
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• 2014

In recent times, the demand for edible medication for the treatment of hyperpigmentation has increased significantly. Therefore, the discovery of a stable, safe and inexpansive antimelanogenic component from natural substances, such as grains, is of particular interest. The levels and activities of some metabolites and/or enzymes can be increased. In the present study, we investigated the antimelanogenic effects of water-soluble extracts from barley (BE), malt (ME) and germinated barley (GBE) in melan-a cells. The inhibitory effects of ME and GBE on melanin production were significantly greater than that of BE. Interestingly, the content of ferulic acid, the proposed active component of barley, was also higher in ME and GBE than in BE by HPLC analysis. Western blot analysis of the expression of melanogenic enzymes in melan-a cells treated with BE, ME or GBE indicated the expression of both tyrosinase and tyrosinase-related protein 2 (TRP-2) significantly decreased after treatment with BE, ME or GBE. These results suggest that besides BE, ME and GBE also inhibit melanin production most likely through suppression of tyrosinase and TRP-2 expression. ME and GBE were more efficacious at inhibiting melanin production than BE was and may also represent potential skin-whitening agents.