• 한국자기공명학회논문지
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• 제24권4호
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• pp.96-103
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• 2020

A new NMR method to monitor solvent-localized NMR signals in the two-phase liquid system is suggested. This method based on intermolecular single-quantum coherence (iSQC). Here, we exploited the feature of the local action of distant dipolar field (DDF) effect in order to filter out specific NMR signals dissolved in different solvents. This solvent specific iSQC spectroscopy was carried out on a model two-phase liquid system (D-glucose in water/palmitic acid in chloroform), and showed solvent-localized NMR signals. We believe our approaches might be useful in metabolic analysis such as two-phase liquid extraction scheme for labile chemical species.

• 한국식품과학회지
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• 제36권3호
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• pp.518-521
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• 2004

이상계 용매시스템을 이용하여 물질을 고순도로 대량 분리 할 수 있는 기술인 countercurrent chromatography를 이용하여 인삼으로부터 생리황성 성분인 saponin을 대량 분리 농축하였다. 용매 조성별 인삼 saponin의 분배계수에 따른 인삼 saponin 분리에 적합한 용매시스템은 chloroform/methanol/water(40/39/21, v/v/v)으로 결정되었으며 HSCCC의 작동 조건은 chloroform/methanol/water 용매시스템의 하층부를 이동상으로 한 head to tail mode에서 이동상의 유속 5mL/min, 인삼추출물 injection량 $200{\mu}L$, 컬럼회전속도 800 rpm의 조건이 적합한 것으로 판단되었다. 이러한 조건하에서 분리된 인삼saponin의 양은 $550.7{\mu}g$으로 HSCCC에 주입한 인삼 추출물 $200{\mu}L$중에 존재하는 총 saponin의 양 $865.5{\mu}g$에 비교하여 전체 수율은 63.6%로 나타났으며 TLC로 각 분획의 순도를 확인할 수 있었다.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2002년도 생물공학의 동향 (X)
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• pp.112-115
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• 2002

본 연구에서는 균주의 배양과 동시에 생산물을 회수할 수 있는 동시추출공정을 건조질량의 $15{\sim}75$ %의 탄화수소를 생산한다고 알려진 B. braunii 배양에 적용하고자 한다. 일반적인 tow-phase 동시 추출공정의 적용시 B. braunii의 경우 생산된 탄화수소가 균주 외벽의 matrix에 강하게 부착되어 있기 때문에, two phase 추출공정 적용시 bubble solumn내에서 단지 폭기에 의한 교반만으로는 충분한 탄화수소의 회수율을 얻을 수가 없었다. 본 연구에서는 배양액과 유기용매층의 접촉기회를 증대시킨 two-stage 동시추출 공정을 개발하여 기존의 two-stage 동시추출 공정보다 2배 이상 높은 57 %의 탄화수소 회수율을 얻을 수가 있었고, 이를 회분배양후 후속분리공정으로 이용할 경우 6시간 추출후 62 %의 회수율을 얻을 수가있었다.

• Elastomers and Composites
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• 제37권4호
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• pp.211-216
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• 2002

서로 다른 고분자 혼합물의 조성 및 농도에서 온도 변화에 따른 상 분리 거동을 관찰하였다. 용매는 EPDM에 poor solvent로, SBR에는 good solvent로 작용하는 벤젠을 사용하였다. Cloud point curves(CPC)에서 각 고분자 시료에 대한 용매의 친화력과 상호 반발력 차이 때문에 15 ℃를 전후하여 CPC에 큰 변화가 있었다. 5℃ ~ 25℃ 영역에서 고분자 혼합물 조성비와 농도에 따라 비상용성이 나타났으며, 분리된 각 상의 조성은 상분리 온도에 크게 의존되어 있음을 확인하였다. EPDM과 SBR의 상호작용 파라메타는 0.6301 ~ 1.0775의 범위로 이 두 고분자 물질은 상용성이 없는 것으로 결론지었다.

• 한국염색가공학회지
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• 제13권2호
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• pp.42-42
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• 2001

Following the prior studs regarding that 1.0g of cotton fabric cound be dyed uniformly with a reactive dye in the solvent mixture of 2㎖ of water and 23㎖ of dichloromethane, silk fabric was dyed with C. I. Reactive Blue 203 in the water/dichloromethane two-phase immiscible solvent media. In order to minimize dye loss due to its hydrolysis, the reactive dyeing was carried out in dichloromethane containing a small amount of water. With only 3㎖ of water in 22㎖ of dichloromethane, 1.0g of silk fabric could be dyed perfectly. The uptake ratio was increased greatly, compared with that of normal reactive dyeing in a water medium. It would seem that the one of hydrophobic solvents, dichloromethane, can assist the even dyeing as it disperses a small amount of dye-dissolved water phase and conveys this water phase to the fabric entirely and uniformly.

• 한국염색가공학회지
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• 제13권2호
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• pp.128-134
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• 2001

Following the prior studs regarding that 1.0g of cotton fabric round be dyed uniformly with a reactive dye in the solvent mixture of $2m\ell$ of water and $23m\ell$ of dichloromethane, silk fabric was dyed with C. I. Reactive Blue 203 in the water/dichloromethane two-phase immiscible solvent media. In order to minimize dye loss due to its hydrolysis, the reactive dyeing was carried out in dichloromethane containing a small amount of water. With only $3m\ell$ of water in $22m\ell$ of dichloromethane, 1.0g of silk fabric could be dyed perfectly. The uptake ratio was increased greatly, compared wish that of normal reactive dyeing in a water medium. It would seem that the one of hydrophobic solvents, dichloromethane, can assist the Even dyeing as it disperses a small amount of dye-dissolved phase and conveys this water phase to the fabric entirely and uniformly.

• 한국막학회:학술대회논문집
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• 한국막학회 1998년도 춘계 총회 및 학술발표회
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• pp.22-24
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• 1998

1. INTRODUCTION : The phase inversion method is widely used to prepare a variety of polymeric membranes ranging from micro-filtration to gas separation. The final morphology obtained by immersion precipitation strongly reflects the thermodynamics and kinetics of the system involved. The equilibrium thermodynamics of the ternary system of polymer/solvent/ nonsolvent is still very important to understand and predict membrane structure. Polysulfone (PSf) and polyethersulfone (PES) are important polymers as membrane materials due to the chemical resistance, mechanical strength, thermal stability and transport properies. There are several reports on the experimental phase diagrams in ternary mixtures of PSf/solvent/nonsolvent, and PES/solvent/nonsolvent. It would be interesting to investigate the solution thermodynamics containing these two polymers since PES is slightly less hyclrophobic than PSf.

• Bulletin of the Korean Chemical Society
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• 제15권3호
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• pp.214-221
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• 1994

We present some results obtained from theoretical study on a non-symmetrical A/BC polymeric system including solvent which consists of two phases, a polymeric phase A on one side and a mixture of polymers B (as a compatibilizer) and C on the other in the presence of a solvent. By employing the functional integral techniques we derive the mean-field equations and solve them numerically to deduce the physical properties of the interface involving the polymers and solvent concentration profiles in the limit that molecular weights of all the polymers involved tend to infinity. The calculations are performed for typical values of the Flory interaction parameters and for the volume fraction of polymer B in the asymptotic phase and of solvent. In the polymers/solvent blend under consideration the interfacial adsorption of polymer B, the solvent concentration, and degrees of the specific interaction between the polymers are found to play important roles in modification of the interfacial properties.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2000년도 추계학술발표대회 및 bio-venture fair
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• pp.229-232
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• 2000

본 연구에서는 균주의 배양과 동시에 생산물을 회수할 수 있는 동시추출공정을 건조질량의 $15{\sim}75%$의 탄화수소를 생산한다고 알려진 B. braunii 배양에 적용하고자 한다. 일반적인 two-phase 동시추출공정의 적용시 B. braunii의 경우 생산된 탄화수소가 균주 외벽의 matrix에 강하게 부착되어 있기 때문에, two phase 추출공정 적용시 bubble column내에서 단지 폭기에 의한 교반만으로는 충분한 탄화수소의 회수율을 얻을 수가 없었다. 본 연구에서는 배양액과 유기용매층의 접촉기회를 증대시킨 two-stage 동시추출 공정을 개발하여 기존의 two-phase 동시추출 공정보다 2배 이상 높은 56.2%의 탄화수소 회수율을 얻을 수가 있었다.

• Journal of Microbiology and Biotechnology
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• 제7권5호
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• pp.345-351
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• 1997

An aqueous/organic two-phase reaction system was applied to the production of catechol using immobilized resting cells of Pseudomonas putida CY 400. Water/ethyl ether system was used because of high partition coefficient of catechol and thus to reduce the product inhibition and degradation. Among the tested immobilization carriers, polyacrylamide gel gave the highest catechol productivity. The immobilization seemed to protect the cells against solvent toxicity. From the simulation of reaction conditions based on two-phase models, it was found that there was an optimum acetate concentration at fixed benzoate and cell concentrations for the catechol productivity. A lower phase volume ratio (lower fraction of organic phase) gave a higher productivity. However, the substrate conversion was low at low phase volume ratio.