• 공업화학
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• 제10권1호
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• pp.112-117
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• 1999

Pulsed Field Gradient NMR(FT-PFGE)을 이용하여 N-alkyl-N, N-dimethylamine oxide/hydrocarbon/$D_2O[C_nDMAO/C_{n^{\prime}}H_{{2n^{\prime}+2}}/D_2O]$ 3성분 계에서 자기확산 계수를 측정하였다. 여기서 n = 12, 14, 16인 계면활성제를 사용하였으며, n' = 6, 8, 10, 12, 14인 탄화수소를 사용하였다. 미셀 상에서 주로 확산은 미셀의 유체역학적 이동에 지배되며, 미셀들의 충돌로 가용화된 탄화수소의 교환에 의해서도 일부 이루어진다. 이 연구는 계면활성제의 알킬 사슬 길이와 탄화수소 분자크기의 변화에 따라서 검토되었다. 그 결과 큐빅 상에서 용매는 물의 연속상에서 거동에 대한 전형적인 자기확산 계수 값을 나타내고, 이때 장애물로서 마이크로에멀젼 액적이 작용한다. 겔 상태에서 계면활성제의 유동성은 낮고, 알킬 사슬 길이가 가장 짧은 계면활성제에 대해서만 결정되었다. 겔 내에서 미셀들 간의 탄화수소 교환은 호핑 과정에 의해서 일어나는 것을 알았고, 회합율은 계면활성제의 알킬 사슬 길이에 따라 감소하였다.

• Macromolecular Research
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• 제11권4호
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• pp.231-235
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• 2003

Phase behavior information is necessary for accomplishing homogeneous copolymerization to obtain high yield of copolymers and prevent a fouling problem. Cloud-point data to $160^{\circ}C$ and 1,450 bar are presented for five $C_6$ hydrocarbon solvents, normal hexane, 2,2-dimethyl butane, 2,3-dimethyl butane, 2-methyl pentane, and 3-methyl pentane, with poly(ethylene-co-53 mol% norbornene) ($PEN_{53}$). The pressure-concentration isotherms measured for $PEN_{53}$/n-hexane have maximums that range between 5 and 12 wt% $PEN_{53}$. The cloud-point curves for $PEN_{53}$ all have negative slopes that decrease in pressure with temperatures. The single-phase region of $PEN_{53}$ in n-hexane is larger than the regions in 2,2-dimethyl butane, 2,3-dimethyl butane, 2-methyl pentane, and 3-methyl pentane. The cloud-point curve of $PEN_{53}$ in 2,2-dimethyl butane is located at higher temperatures and pressures than the curve in 2,3-dimethyl butane due to the reduced dispersion interactions with and limited access of 2,2-dimethyl butane to the copolymer. Similar cloud-point behavior is observed for $PEN_{53}$ in 2-methyl pentane and 3-methyl pentane.

• 한국자원식물학회지
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• 제10권4호
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• pp.324-333
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• 1997

남부지방에 서식하는 식물체 중에서 꽃기린, 민들레, 박주가리, 후박나무, 팔손이나무, 달맞이꽃, 동백나무 그리고 유동나무를 대상으로 지질 및 탄화수소를 분석한 결과를 요약하면 다음과 같다. 1. 지질함량이 높은 식물체는 유동나무와 동백나무이었으며, 유동나무의 경우 중성지질 함량은 $52.9\sim66.0g/100g$, 인지질 함량은 $0.57{\sim}1.37g/100g$이었고, 동백나무의 경우, 중성지질 함량은 $59.1\sim62.3g/100g$, 인지질 함량은 $0.72\sim1.44g/100g$이었다. 2. 실험대상 식물체 모두에서 지질을 구성하는 지방산의 종류를 분석한 결과, palmitic acid, oleic acid 그리고 linoleic acid의 함량이 높게 나타났다. 3. 탄화수소의 함량은 실험대상 식물체 중 팔손이 나무에서 3.02mg/g으로 가장 높게 나타났다. 4. 실험대상 전식물체에서 주로 함유되어 있는 탄화수소는 탄소수 16 이사으이 것이었다.

• 대한화장품학회지
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• 제36권1호
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• pp.17-32
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• 2010

본 총설에서는 이산화탄소에 용해력이 있는 새로운 탄화수소 공중합체의 설계와 개발, 그리고 생체친화성 고분자의 초임계 중합을 위한 효과적인 계면활성제로써의 성능에 대해 소개하고, 초입계 유체의 기본적 개념을 용매로서의 성질과 고분자 합성분야에서의 응용적인 측면에서 기술한다. 이산화탄소에 높은 용해력을 지닌 탄화수소 고분자 중합을 위해 새로운 리빙라디칼 중합기술을 사용하였고, 이 물질들의 이산화탄소 내에서의 상거동을 측정하여 공중합체의 분자량과 구조가 용해도에 미치는 영향을 조사하였다. 초임계 분산중합에서의 효과적인 계면활성력을 확인하였고, 성장하는 입자의 안정화에 필요한 키 파라미터를 결정하기 위해 다양한 조건에서 실험을 수행하였으며, 화장품 분야에 응용될 수 있는 새로운 구조의 친환경 고분자 소재 개발에 이 연구가 작용될 수 있다는 잠재적인 가능성을 확인하였다.

• 한국의류학회지
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• 제12권3호
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• pp.383-390
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• 1988

To investigate the soil-redeposition and color change on dry-cleaning, the white and, dyed, fabrics of cotton, silk, polyester and viscose rayon were put into ordinary commercial dry-cleaning machine with soiled cloths. The solvents used were hydrocarben, perchloroethylene and fluorocarbon. From the result, we obtained the following conclusions by examining soil-redeposition, color difference of fabrics and tenacity of cotton fabric. 1. In case of white fabrics, as a whole, perchloroethylene shows the lowest soil redeposition. When distillation process is adopted, the rate of soil redeposition is lowered. with hydrocarbon sdvent. The order of soil redeposition rate of fibers are following; cotton> viscose rayon> silk> polyester. 2. In case of dyed fabrics, the color difference between soil redeposited fabrics and originals ($\delta\;E_1$) is similar with white fabrics in pattern, and the order is cotton, viscose rayon, silk and polyester. The color difference between fabrics, treated by pure solvents and originals ($\delta\;E_2$ ) is also validated as a little. It seems to be due to the bleeding of dyestuffs from fabrics. 3. There is a little change of tenacity of cotton fabrics by dry-cleaning with perchloroethylene solvent. It is supposed that the damage is more influenced the repetitive mechanical action during dry-cleaning than by acidity of the solvent having the acid value of 0,14.

• 한국산업보건학회지
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• 제11권2호
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• pp.153-160
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• 2001

Objectives : The authors evaluated the effects on renal function of workers chronically exposed to low-level organic solvent mixtures. Methods : The authors measured the level of urine ${\beta}2$-microglobulin(${\beta}2$-MG) and microalbumin as biochemical markers of renal function and damage in 29 male workers exposed to organic solvents for more than five years and compared their results with those of 30 male office clerks as a reference group. Results : 1. The mean values of hemoglobin, hematocrit, SGOT, SGPT, ${\gamma}$-GTP were all within normal limits and there was no significant difference, except for hemoglobin(p<0.01), between exposed and reference group. 2. The values of BUN and serum creatinine were within reference limits and there was no significant difference between exposed and reference group. 3. The difference of mean values of urine microalbumin corrected by urine creatinine were statistically significant (p<0.01), but those of urine ${\beta}2$-MG was not. 4. There were no correlation of urine hippuric acids with BUN, serum creatinine, urine microalbumin and ${\beta}2$-MG. 5. There were no significant difference of BUN, serum creatinine, urine microalbumin and ${\beta}2$-MG upon work duration. Conclusions: It is assumed that chronic low-level organic solvent exposure in these workers shows early renal dysfunction, glomerular changes. The result corresponds to previous studies showing the relationship between hydrocarbon exposure and glomerulonephritis. For evaluation of impairment on kidney tubules, we need further study using more precise markers and long-term follow-up.

• 한국윤활학회:학술대회논문집
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• 한국윤활학회 2002년도 proceedings of the second asia international conference on tribology
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• pp.83-84
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• 2002

For estimation of chain-matching phenomena between normal paraffin as a solvent and straight-chain fatty acid as an additive, the density measurement of n-dodecane, n-tetradecane and n-hexadecane were carried out at oil temperature 313K and pressure up to 1.3 GPa. Their solidification pressure were easily determined by the appearance of molecular crystal, abrupt volumetric contraction and generation of heat of solidification and showed minima under the matching condition. The bulk modulus K of molecular crystal was evaluated using phase diagram. The bulk modulus showed maxima under the each matching condition. The chain matching effect on the bulk modulus beyond the scope of the interfacial phenomena are confirmed.

• 대한약침학회지
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• 제11권3호
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• pp.79-91
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• 2008

Objective: The purpose of this study was to investigate the composition for pharmacopunctures of eight principles hydrodistillation layer. Methods: The study was determined the hydrodistillation layer for pharmacopunctures of eight principles by hydrodistillation method. The effective components in hydrodistillation layer for pharmacopunctures of eight principles were extracted with ethyl ether or dichloromethane, and then analyzed by Gas Chromatography/Mass Spectrometry(GC/MS). Results: 1. Analyzed pharmacopunctures of eight principles by GC/MS, a lot of differences according to extraction solvent by each pharmacopunctures of eight principles and specific peak patterns were seen. 2. The main compound in pharmacopunctures of eight principles was a kind of hexaoxacyclohydrocarbon that has long hydrocarbon chain.

• 한국환경과학회:학술대회논문집
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• 한국환경과학회 2003년도 International Symposium on Clean Environment
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• pp.119-122
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• 2003

Quantitation methods of total petroleum hydrocarbons to determinate oil contaminated level in soil were discussed. Extraction characteristics of several pretreatment methods and practical detection limit and reappearances in gas chromatography/mass spectrometry. with each pretreatment method were investigated. The obtained results showed that the newly adopted quantitation method and mechanical shaking extraction method using methanol with extraction solvent are more practical and applicable to real sample than the conventional methods. In applying these methods to gasoline, kerosene, fuel oil which are major source of soil contamination, the practical quantitation limit and % relative standard deviation was able to determine with range of 2.5 - 10 ppm, 5 - 7 ％.

• 복식
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• 제47권
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• pp.89-100
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• 1999

This study was carried to a textile conservation process included washing effect fiber analysis such as fiber identification fabric density and thickness color fading and of extracted soils. the following results were obtained. 1. AS a result of investigating to fabric surfaces by S.E.M all of cleaning methods wet cleaning-solvent cleaning in charge system were effective to remove soils from fabrics. 2. The buried fabrics were made of silk few of them were cotton ramie and hemp. 3. According to fabric density and thickness used fabrics were almost medium weight fabrics. 4. Low values of L, a, b indicated that the colors of these fabrics were faded to yellow and brown. 5. The soil components were hydrocarbon-alkane group alkyl alcohol and ketone group.