• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.21 no.3
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• pp.236-241
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• 2008

The effect of organic solvent mixture ratio on the rheology property of slurry and thickness control of ceramic green sheet was investigated. For selecting a suitable dispersant multiple light scattering method was used to evaluate the particle migration velocity and variation of clarification layer thickness. Using the selected dispersant the dispersion property of solution according to solvent mixture ratio was investigated. Binder and plasticizers were added to formulate slurries and their viscosity was evaluated according to solvent mixture ratio. Ceramic green sheets with average thickness of 30, 50 urn were fabricated via tape casting and their thickness tolerances measured. As a result according to solvent mixture ratio the solution and slurry properties varied and for the mixture ratio of ethanol/toluene of 80/20 the ceramic green sheet with the lowest thickness tolerance was obtained.

• Food Science and Preservation
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• v.8 no.2
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• pp.157-163
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• 2001

Optimal conditions for hot water extraction of Liriope spicata tuber were investigated with changes in solvent ratio(2∼6 fold) and heating time(1∼5 hr) by response surface methodology. The content of extractable solids increased with an increased in solvent ratio, and the highest content showed at heating time of 3 hr. The content of total steroid saponin increased with a decrease in solvent ratio, and increased with an increase in heating time at increasing the solvent ratio. The content of non-reducing sugar containing oligosaccharides at a lower solvent ratio didn’t show changes depending on heating time, while that at a higher ration decreased with an increase in heating time. Optimal extraction conditions using hot water as the limited conditions of 15∼18% extractable solids, 1.5∼2.0% total steroid saponin, 6∼8% reducing sugar, 6∼7% non-reducing sugar and 13∼15 brix were 3 hrs of heating time and 4 fold of solvent ratio.

• Journal of the Korean Wood Science and Technology
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• v.51 no.6
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• pp.481-492
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• 2023

The ecofriendly lifestyle has attracted considerable support for sustainable development. Natural dyes, as sustainable products, have become a research focus and development area for many scientists. Ecofriendly processing also supports circular sustainable development. This study effectively obtained tannins as a natural dye from merbau (Intsia bijuga) sawdust using water as an ecofriendly solvent. Merbau sawdust is an underutilized industrial waste. Temperature and solid-solvent ratio variations were performed to extract tannins from merbau sawdust. Temperature and solid-solvent ratio positively affected solution yield and tannin concentration. The optimal condition was identified using response surface methodology and experimental observations. A yield of 0.2217 g tannins/g merbau was obtained under the conditions of 333.15 K and 0.125 solid-solvent ratio. Extraction was controlled by convective mass transfer at the interface of solid particles.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.39 no.3
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• pp.70-76
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• 2007

The raw oriental lacquer produced in China was used in this study. This lacquer was diluted with ethanol and terpene in different solvent ratios. The diluted lacquer in the solvents had two layers. The upper layer was solvent soluble and the lower contained precipitates. Hanji was treated with the solvent solubles and the mixture containing precipitates, and then properties of the Hanji were evaluated. The average weight, thickness, and density of Hanji treated with oriental lacquer tended to gradually be decreased as the lower concentration of lacquer was used and as the solvent soluble was treated. Tensile strength of the treated Hanji decreased when the diluted lacquer was used and Hanji treated with terpene dilution at the ratio of lacquer to solvent of 1:5 (v/v) showed higher tensile strength than ones treated with ethanol dilution. The folding endurance decreased as the less concentrated lacquer was used and the highest value was obtained when 1:40 (v/v) of lacquer to solvent ratio in both ethanol and terpene mixture. Absorption ratio was higher in the Hanji treated with ethanol mixture, treated with the lacquer in lower concentration, and treated with ethanol mixture. Hanji treated with ethanol dilution at 1:20 (v/v) and the lower ratio of lacquer to solvent showed a hydrophobic property. Amount of the bound dye materials tended to be decreasing as the concentration of lacquer became lower and it was higher in Hanji treated with ethanol mixture than with terpene mixture.

• Tribology and Lubricants
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• v.3 no.2
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• pp.34-43
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• 1987

The effect of dilution solvent ratio, and the mixing ratio of MEK and toluene on the solvent dewaxing process has been studied. The results of this study are Summarized as follows; 1. The best mixing ratio of solvent of MEK process and Toluene when in case of light and medium Waxy oils, which has low viscosity was 48: 52, and when in case of heavy waxy oil, which has high viscosity was 45: 55. 2. The best dilution solvent ratio when in case of low viscosity oils. was 1:2.8 against waxy oils after annexing 5 times divided as well as, when incase of high viscosity oil was 1:3.5 after annexing 2 times divided. 3. The chilling temperature was -26$\circ$C and the reguired dewaxing time depends on the viscosity of waxy oils.

• Food Science and Biotechnology
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• v.14 no.6
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• pp.836-840
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• 2005

Extraction characteristics of Bonus species of Brassica oleracea var. capita and functional properties of corresponding extract were monitored by response surface methodology (RSM). Maximum extraction yield of 44.07% was obtained at ratio of solvent to sample of 27.94 mL/g, ethanol concentration of 24.35%, and extraction temperature of $55.21^{\circ}C$. At ratio of solvent to sample, ethanol concentration, and extraction temperature of 21.11 mL/g, 58.53%, and $68.83^{\circ}C$, respectively, maximum electron-donating ability was 48.44%. Maximum inhibitory effect on tyrosinase was 68.94% at ratio of solvent to sample, ethanol concentration, and extraction temperature of 24.08 mL/g, 10.49%, and $78.71^{\circ}C$, respectively. Superoxide dismutase (SOD) showed maximum pseudo-activity of 24.78% at ratio of solvent to sample of 22.66 mL/g, ethanol concentration of 45.69%, and extraction temperature of $93.81^{\circ}C$. Based on superimposition of four-dimensional RSM with respect to extraction yield, electron-donating ability, and pseudo-activity of SOD, optimum ranges of extraction conditions were ratio of solvent to sample of 20-30 mL/g, ethanol concentration of 35-65%, and extraction temperature of $50-80^{\circ}C$.

• Bulletin of the Korean Chemical Society
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• v.28 no.11
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• pp.2051-2055
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• 2007

The solvent effect on sulfur ylide mediated epoxidation reaction was studied systematically. While higher trans/cis ratio of the epoxide was obtained in the more polar solvent, protic solvent produced the lower trans/ cis ratio than any aprotic solvent.

• Clean Technology
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• v.23 no.3
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• pp.279-285
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• 2017

In this study, a new organophosphorus acid-based solvent (KMC-P) from KMC Co., Ltd. was used for the recovery of the iron chloride etching waste solution. In order to increase the extraction efficiency for the new solvent in the solvent extraction process, we selected the process variables and conducted the optimization experiment according to the DOE to investigate the correlation between the variables. Solvent concentration, pH, and O/A ratio were found to be factors affecting extraction and stripping efficiency. The optimum stripping efficiency was 69.7% when the solvent concentration was 29.4 wt%, the HCl addition amount was 0 mL, and the O/A ratio was 7, and the reliability was more than 86%.

• Polymer(Korea)
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• v.25 no.6
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• pp.811-817
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• 2001

Crystallization behaviour of bisphenol A polycarbonate(PC) from amorphous phase was studied by varing solvent/nonsolvent ratios in liquid phase. Chloroform and isopropanol were used as a solvent and a nonsolvent, respectively. Samples were characterized by optical microphotography, scanning electron microscope (SEM), X-ray diffaction (XRD), and differential scanning calorimeter (DSC). DSC and XRD measurement were used to determine the crystallinity of PC. The solubility constant seems to critical to control the PC crystallinity in solvent/nonsolvent mixture. The difference in PC crystallinity is explained by the difference in solubility constant of the mixture depending on the solvent/nonsolvent ratio. PC solution of 75/25 wt% (solvent/nonsolvent) ratio produced PC powder showing maximum crystallinity. At this condition solubility constant (9.85) of the mixed solvent was close to PC (9.9).

• KSBB Journal
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• v.28 no.4
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• pp.238-243
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• 2013

Astaxanthin is one of the carotenoid with strong antioxidant. The conditions of extraction of astaxanthin from Portunus trituberculatus were optimized in this work. Six factors of conditions such as, extraction method, extraction solvent, ratio of solvent to raw material, temperature, and time, were investigated. For the increase of the extraction yield, ionic liquids were used as additives in the extraction solvent. The optimum extraction conditions were found: heat reflux extraction, Dichloromethane/methanol (25:75, v/v) as solvent, 1:30 of the ratio of solvent raw material, $80^{\circ}C$, 90 min, and ionic liquid as additive. As a result, 45.81 ${\mu}g/g$ of astaxanthin was extracted from waste.