• Journal of Electrochemical Science and Technology
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• 제12권4호
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• pp.387-397
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• 2021

Deep eutectic solvents have been established as feasible metal electroplating solvent alternatives over traditional toxic aqueous plating baths. However, water, either added intentionally or unintentionally, can significantly influence the solvent's physical properties and performance, thereby hindering its industry application. In this study, the hygroscopicity, or the ability to absorb moisture from the environment, of synthesized ethaline (1:2 choline chloride:ethylene glycol) was investigated. The kinematic viscosity, electrical conductivity, electrochemical window, and water content of ethaline were monitored over a 2-week period. Karl Fischer titration tests showed that ethaline exposed to the atmosphere displayed significant hygroscopicity compared to its unexposed counterpart. ¹H NMR spectroscopy revealed that water vapor was readily absorbed at the surface due to the hydrophilic groups present in the ethaline molecule. Water uptake resulted in the decrease in viscosity, increase in electrical conductivity and narrowing of the electrochemical window of ethaline. Solution heating at 100℃ removed the absorbed moisture and allowed the recovery of the solvent's initial properties.

• 한국세라믹학회지
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• 제25권6호
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• pp.677-684
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• 1988

Titania powders were obtained from the various hydrolysis condition the variation of Alkoxide, water/Alcohol, REaction, Temp., reaction time and solvent system were investigated. In this result, spherical monodisperesed titania gel powders(≒0.7${\mu}{\textrm}{m}$) were obtained using EtOH(as solvent), and this method had rapid reaction time compare with iso-PrOH(as solvent).

• Korean Chemical Engineering Research
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• 제46권5호
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• pp.965-970
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• 2008

접촉분해경유의 산화반응후 포함된 산화황화합물을 분리하기위해 다양한 용매를 사용하여 용매추출에 관한 연구를 수행하였다. 용매로는 극성을 가진 물, N-메틸피놀리논, 에틸아세테이트, 디메틸포름아마이드, 이소프로필알코올, 아세토니트릴, 메탄올등을 사용하였다. 실험결과, 접촉분해경유와 용매와의 층분리는 적절한 양의 물을 첨가한 경우에 이루어졌으며, 물과 N-메틸피놀리논을 혼합한 혼합용매가 접촉분해경유로부터 산화황화합물의 선택적인 분리에 가장 적절하였다. 또한 접촉분해경유로부터 황화합물을 99.5% 이상으로 제거하기 위해선, 4단 정도의 평형추출이 필요하였다.

• 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.

• The Korean Journal of Ceramics
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• 제7권1호
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• pp.16-19
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• 2001

For the fast dry of the aqueous tape, the process which water was reaplaced by organic solvent was proposed. Socalled, it was the solvent washing dry. Three organic solvents (methanol, ethanol and acetone) were selected for the washing solvent. The weight loss of the washed tapes was measured to evaluate the dry rate of the tapes and dried tapes were examined the generation of the cracks with the variations of the organic solvent and the washing time. Methanol, ethanol and acetone were available organic solvents for this method. The tapes washed in methanol, ethanol and acetone were dried rapidly for twenty minutes. After thirty minutes, the weight losses were not found any more, The solvent of the lower surface tension can decreases the crack of dried tape. If solvent substitutes water completely, though it was fast dried, crack can be eliminated.

• Bulletin of the Korean Chemical Society
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• 제24권1호
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• pp.55-59
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• 2003

This work is focused on analyzing ion-pair interactions and showing the effect of solvent induced inter-atomic attractions in various dielectric environments. To estimate the stability of ion-pairs, SCI-PCM ab initio MO calculations were carried out. We show that the solvent-induced attraction or ‘cavitation' energy of the ion-pair interactions in solution that arises mainly from the stabilization of the water molecules by the generation of an electrostatic field. In fact, even the strong electrostatic interaction characteristic of ion-pair interactions in the gas phase cannot overcome the destabilization or reorganization of the water molecules around solute cavities that arise from cancellation of the electrostatic field. The solvent environment, possibly supplemented by some specific solvent molecules, may help place the solute molecule in a cavity whose surroundings are characterized by an infinite polarizable dielectric medium. This behavior suggests that hydrophobic residues at a protein surface could easily contact the side chains of other nearby residues through the solvent environment, instead of by direct intra-molecular interactions.

• Journal of Pharmaceutical Investigation
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• 제15권3호
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• pp.100-112
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• 1985

Dissolution characteristics of flurbiprofen solvent deposited on ${\alpha}-cyclodextrin$, ${\beta}-cyclodextrin$, lactose and corn starch were studied to evaluate the pharmaceutical aspects of solvent deposition method where drug was solvent deposited on the surface of excipients. In a solvent deposition system, the drug to excipient ratio and kind of excipient affect much on dissolution rates of flurbiprofen. The solvent deposition system formation was confirmed by scanning electron microscope. By increasing the amounts of matrix, it was possible to enhance the dissolution rate of flurbiprofen solvent deposition system. The amount of flurbiprofen dissolved from ${\beta}-cyclodextrin$ deposition system (1:10) at 60 minutes was enhanced 6.5 times in water and 28 times in simulated gastric juice compared with flurbiprofen alone. Flurbiprofen solvent deposited system (1:10) enhanced dissolution rate greater than inclusion complex and dispersion system.

• 한국의류학회지
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• 제22권1호
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• pp.100-107
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• 1998

Polyester filaments were dyed with disperse dye in dyebath containing water and water miscible organic solvents . acetone, 1,4-dioxane, DMF. In case of Acetone and 1,4-dioxane, the equilibrium dyeuptake was maximun at the volume fraction 0.05. The equilibrium dye uptakes were decreased as volun~e fraction of organic solvents were increased. When the volume fractions of water miscible organic solvents were varied, dye uptake was increased constantly with dyeing time. In dyebath containing water and water miscible organicsolvent, the dyeuptake was increased quickly during initial 40∼ 60 min. and slowly increased there after. The slope of Ct/Coo to t was greater in dyebath containing water and water miscible organic solvents than dyebath containing water. The differences of the slope with volulne fractions of water miscible organic solvent were not shown big.

• Bulletin of the Korean Chemical Society
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• 제33권3호
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• pp.825-827
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• 2012

In this study, the variation in surface morphology of copper phthalocyanine (CuPc) thin films treated with a flow of acetone vapor assisted by nitrogen carrier gas was investigated. The CuPc nanorods with similar dimensions were well dispersed throughout the whole film surfaces after ~20 min. of treatment. However, the electronic absorption spectra only changed slightly, which indicates that molecular stacking was not altered during treatment. This treating method is simple and more advantageous compared to other solvent treating technologies such as mixed solvent spray treatment using organic solvents and water since it requires relatively mild treating conditions and does not need the presence of water.

• 한국고분자학회:학술대회논문집
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• 한국고분자학회 2006년도 IUPAC International Symposium on Advanced Polymers for Emerging Technologies
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• pp.307-307
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• 2006

The reduction behavior of silver ions to silver nanoparticles is an important research topic in polymer/silver salt complex membranes for facilitated olefin transport, because it has a significant effect on the long-term stability of membrane performance. In this study, the effects of solvent on the formation of silver nanoparticles and long-term membrane performance in polymer/silver salt complex membrane were investigated. This effect was assessed for the complexes of poly(N-vinyl pyrrolidone) $(PVP)/AgBF_{4}$ with the use of ionic liquid (IL), acetonitrile (ACN) and water as a solvent. Membrane performance test shows that long-term stability is strongly dependent on the kind of solvent and arranged: IL > ACN >> water.