• Proceedings of the Korea Air Pollution Research Association Conference
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• 2000.11a
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• pp.94-95
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• 2000

PCBs(polychlorinated biphenyls)와 BHCs(benzene hexachlorides)와 같은 SOCs(semivolatile organic compounds)는 모든 대륙에서 검출되어지고 있으며, 심지어 장거리 수송에 의해 청정지역인 북극에서도 검출되고 있다. 이들 성분들은 친지질성(lipophilic)으로 대부분이 가스상으로 존재하여 식물의 표면에 존재하는 지질(lipid)에 건성침착(dry deposition) 또는 습성 침착(wet deposition)된다. 이렇게 침착된 성분들의 농도는 대기중 농도와 밀접한 관계가 있다고 보고되고 있다(천만영,1998; Simonich and Mites, 1995). (중략)

• Proceedings of the KAIS Fall Conference
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• 2007.11a
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• pp.356-358
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• 2007

본 논문에서는 농도가 다른 EC계의 전해질 용액 중에서 흑연의 Cyclic voltammetry(CV)를 측정하였다. CV후 전극표면에 생성된 SEI를 투과형 전자현미경으로 분석한 결과, PC계에서 얻어지는 결과와 유사하게 충 방전 반응 및 생성된 SEI의 성질이 전해질의 농도에 크게 의존하고 있음을 확인하였다.

• Korean Journal of Soil Science and Fertilizer
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• v.30 no.2
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• pp.99-107
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• 1997

The effect of easily decomposable organic carbon (methanol) application on the behavior of nitrogen derived from surface-applied urea in submerged soil was investigated. Two rates of urea (150 & $300kg-N\;ha^{-1}$) and three levels of methanol (2, 4, 8 ml) were applied to 10 g soil samples. The samples were incubated for 30 days under submerged conditions. The flood water and the soil were sampled for analysis of urea-N, $NH_4-N$ and $NO_3-N$ every 10 days. Urea-N in flood water and in soil at the rate of $150kg-N\;ha^{-1}$ and that in flood water at the rate of $300kg-N\;ha^{-1}$ were not detected but the urea-N concentration in soil at the rate of $300kg-N\;ha^{-1}$ with 8 ml methanol treatment was 4.7 on the 10th day from incubation. $NH_4-N$ concentrations in flood water and in soil increased with increasing urea application rates whereas they decreased with increasing methanol treatment. $NO_3-N$ concentration in flood water and in soil were similar regardless of the urea and methanol application rates. The total amount of $NH_4-N$ in flood water and in soil decreased with increasing methanol treatment, 0 ml & 2 ml, whereas the total amounts of $NO_3-N$ in both flood water and soil increased slightly at higher rates of methanol treatment, 4 ml & 8 ml. The total amount of $NH_4-N$ in both flood water and soil increased up to 20 days of incubation whereas that of $NO_3-N$ in flood water and in soil decreased over incubation time.

• Applied Chemistry for Engineering
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• v.7 no.2
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• pp.215-220
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• 1996

Nine kinds of amphoteric surfactants were derived from 1-(2-hydroxyethyl)-2-undecyl-2-imidazoline. Their surface activities including surface tension and isoelectric points were measured in aqueous solution and critical micelle concentration(cmc) was also evaluated by the measurement of surface tension. From the measurement of surface tension, carboxylated amides revealed to be 26~40dyne/cm at $4.0{\times}10^{-4}{\sim}1.0{\times}10^{-3}mol/{\ell}$, sulfonated or sulfated imidazolines, 30~35 dyne/cm at $1.5{\times}10^{-3}{\sim}2.5{\times}10^{-3}mol/{\ell}$ and sulfonated amides, 25~33 dyne/cm at $5.8{\times}10^{-4}{\sim}8.0{\times}10^{-4}mol/{\ell}$ concentration range. It was found that isoelectric points of carboxylated amides were pH 7.2~7.9 and those of sulfonated or sulfated imidazolines and sulfonated amides were pH 4.5~5.5.

• Korean Journal of Food Science and Technology
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• v.38 no.6
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• pp.762-766
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• 2006

To improve water resistance of paperboard used to manufacture the corrugated boxes, effect of surface coating of the liner- board with Na-alginate was investigated by determining the optimum processing conditions such as a optimum alginate concentration for surface coating, plasticizer content, concentration of divalent cations their immersion times, For the surface coating of the liner-board, 2.5% Na-alginate solution was found to be the optimum concentration, and the concentration of glycerol used as plasticizer was effective when 35% alginate concentration was use was Used Immersion of the alginate coated paperboard for 3 min in a $CaCl_2$ solution improved the water resistance properties. As a divalent cation for the insolubilization of the alginate films, $Cu^{2+}$ was found to be as effective as $Ca^{2+}$. Among the platicizers tested, sorbitol was the most effective in reducing water vapor permeability and water solubility of alginate coated paperboard.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.33 no.1 s.60
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• pp.7-10
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• 2007

The interaction between polymers and surfactants was investigated by means of rheological and surface tension measurements. The polymers used in this study were acrylates/$C_{10-30}$ alkyl acrylate crosspolymer (AC) and ammonium acryloyldimethyltaurate/VP copolymer (AV). And the surfactants were PEG-40 hydrogenated castor oil (HC) and polysorbate 60 (P60). HC and P60 made the micelles intervening between AC polymers, resulting in the increase of viscosity. However, HC showed a similar behavior over the wider range of surfactant concentration than P60. Regarding of surface tensions in the same range of surfactant concentration, AC/HC solution showed the area of increasing surface tension with surfactant concentration in contrast to the AC/P60 solution showing no increasing area. It is assumed that the micelles between AC/HC were formed so cooperatively and strongly that the surfactants located at the surface originally moved to the micelles.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.11 no.3
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• pp.89-95
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• 2001

The CZ-silicon crystal was annealed at $1350^{\circ}C$ to dissolve the vacancy type grown-in defects. A this temperature, the equilibrium concentration of the oxygen in the silicon crystal is around $1.7{\times}10^{18}$ which induces the oxygen undersaturation in the silicon crystal. This situation results in the faster dissolution of the grown-in defects in the bulk of the silicon wafer than near the surface. This indicates the possibility that the presence of the higher concentration of silicon interstitial hinders the dissolution of the grown-in defects, which were known to compose of the vacancy clusters with surrounding silicon oxide film. This expectation was confirmed by the observation that the slower dissolution of the grown-in defects near the surface of the silicon wafer in the oxygen atmosphere than in the argon atmosphere. This result is quite opposite to the previous argument hat presence of the excess silicon interstitial leads to faster dissolution of the vacancy type defects.

• 대한치과교정학회:학술대회논문집
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• 1998.10a
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• pp.77.3-77.3
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• 1998

• 기계와재료
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• v.10 no.3 s.37
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• pp.141-150
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• 1998

• Applied Biological Chemistry
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• v.37 no.4
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• pp.259-265
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• 1994

To investigate the effects of protein concentration, heat treatment and pH on the foaming properties of sodium caseinate, surface tension, apparent viscosity, turbidity, foaming ability and foam stability at 1.0, 3.0, 5.0, 7.0 and 10.0% (W/V), at 55 and $65^{\circ}C$ and at pH 6.0, 7.0 and 8.0 were examined. The conditions of protein concentrations for the foaming abilities were $3.0{\sim}7.0%$ (W/V). Foam stabilities of heated sodium caseinates were worse than those of unheated sodium caseinates (control) at pH6.0 and 7.0 (p<0.05), while the heated one were better than the unheated at pH 8.0, 10.0% concentrations (p<0.05). Also foam stabilities of sodium caseinate at pH 6.0 were higher than those at pH 7.0 and 8.0. Foaming ability and foam stability were inconsistently effected by changing protein concentration, heat treatment and pH.