• Journal of the Korean Chemical Society
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• v.32 no.3
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• pp.249-259
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• 1988

The solvent effects of MeOH-solvent dimers were studied via AM1 Hamiltonian and supermolecule methods. Methanol, ethanol, acetone, dimethylsulfoxide, N,N-dimethylformamide, tetrahydrofuran, dioxane, and acetonitrile were considered as solvent molecules. Optimized geometries, electron densities, molecular energies, and hydrogen-bonding energies of monomers and dimers were calculated. We found that the stabilization energies contributed to the hydrogen-bonding were decreased in the order of dimethylsulfoxide > ethanol > N,N-dimethylformamide > acetone > methanol > tatrahydrofuran > dioxane > acetonitrile, and this order was explained by using the change of electron density and energy partition functions.

• Proceedings of the Membrane Society of Korea Conference
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• 2003.07a
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• pp.107-114
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• 2003

This study investigated the effect of 2-methoxy ethanol (2-Me) non-solvent as additive included in casting solution. Macroporous polymer membranes were prepared by using polyethersufone (PES)/N-methyl-2-pyrrolidone (NMP)/2-Me casting solution and water coagulant. The phase separation co-process of the vapor-induced phase separation (VIPS) and liquid-induced phase separation (LIPS) were used by means of membrane preparation method. The pore size and pore size distribution were controlled with additive (non-solvent), and measured with Automated Perm Porometer. By increasing additive (non-solvent) in the casting solution, the membranes produced changed from finger structure to sponge structure. That is due to the different diffusion rates. At slow diffusion process, sponge-like structure was formed and at fast diffusion process, finger-like structure was formed. Also relative humidity, evaporation time, temperature of casting solution and coagulation bath etc. had effects on the pore size distribution and the porosity of the membrane.

• Preventive Nutrition and Food Science
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• v.19 no.4
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• pp.261-267
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• 2014

As a part of ongoing research to elucidate and characterize antioxidant and anti-inflammatory nutraceuticals, solvent-partitioned fractions from Spergularia marina were tested for their ability to scavenge radicals and suppress inflammation. The results of the 2',7'-dichlorofluorescein diacetate assay indicate that solvent-partitioned fractions from S. marina scavenged intracellular radicals in $H_2O_2$-stimulated mouse macrophages. The tested fractions decreased the generation of nitric oxide (NO) and the expression of inflammation mediators, namely, inducible nitric oxide synthase (iNOS) and interleukin (IL)-6, by lipopolysaccharide (LPS)-induced mouse macrophages, indicating that S. marina decreases inflammation. Among all tested fractions [i.e., $H_2O$, n-buthanol (n-BuOH), 85% aqueous methanol (aq. MeOH), and n-hexane], the 85% aq. MeOH fraction showed the strongest antioxidant and anti-inflammatory response. The 85% aq. MeOH fraction scavenged 80% of the free radicals produced by $H_2O_2$-induced control cells. In addition, NO production was 98% lower in 85% aq. MeOH fraction-treated cells compared to LPS-induced control cells. The mRNA expression of iNOS and IL-6 was also suppressed in 85% aq. MeOH fraction-treated cells. The results of the current study suggest that the phenolic compound components of S. marina are responsible for its antioxidant and anti-inflammatory effects.

• Bulletin of the Korean Chemical Society
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• v.21 no.5
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• pp.503-509
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• 2000

The solvent effects on the relative free energies of solvation and the difference in partition coefficients (log P) for $Rb^+$ to $K^+$ mutation in several solvents have been investigated using Monte Carlo simulation (MCS) of statistical perturbation theory(SPT). In comparing the relative free energies for interconversion of one ion pair, $Rb^+$ to $K^+$, in $H_2O$(TIP4P) in this study with the relative free energies of the computer simulations and the experimental, we found that the figure in this study with the relative free energies of the computert simulations and the experimental, we found that the figure in this study is $-5.00\pm0.11$ kcal/mol and those of the computer simulations are $-5.40\pm1.9$, -5.5, and -5.4 kcal/mol. The experimental is -5.1 kcal/mol. There is good agreement among various studies, taking into account both methods used to obtain the hydration free energies and standard deviations. There is also good agreement between the calculated structural properties of this study and the simulations, ab initio and the experimental results. We have explained the deviation of the relationship between the free energy difference and the Onsager dielectric function of solvents by the electron pair donor properties of the solvents. For the $Rb^+$ and $K^+$ ion pair, the Onsager dielectric function of solvents (or solvent permittivity), donor number of solvent and the differences in solvation dominate the differences in the relative free energies of solvation and partition coefficients.

• Journal of Applied Biological Chemistry
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• v.65 no.4
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• pp.453-456
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• 2022

Phragmites communis rhizome (Phragmitis rhizoma) was extracted with 70% ethanol, and then the extract was fractionated sequentially using n-hexane, chloroform, and ethyl acetate as solvents. Among the solvent fractions of Phragmitis rhizoma extract, the polyphenol content in ethyl acetate fraction was the highest. The chloroform and ethyl acetate fractions possessed a good nitrite scavenging activity. In addition, each solvent fraction showed an effective lipid peroxidation inhibitory ability at a concentration of 10 mg/mL.

• Current Research on Agriculture and Life Sciences
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• v.28
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• pp.25-29
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• 2010

The colored sweet potato, particularly purple sweet potato, has been well known to contain anthocyanins abundantly. This study was conducted to examine the antioxidant properties of purple sweet potato. The chopped purple sweet potato was extracted 2 times with water or acetone for 18 hours at $28^{\circ}C$. The antioxidative potential of each solvent extract was assessed by DPPH free radical scavenging activity assay, FRAP assay, and total phenolic contents. The results showed that both extracts had not only high DPPH free radical scavenging activity but had high level of total phenolic compounds. Furthermore, both solvent extracts were found to have antioxidative effects in human colon cancer cells (HCT 116, HT 29) in DCFDA assay. The notable antioxidant activity of purple sweet potato suggests its significant health benefit and deserves further study to develop into functional food ingredient.

• Journal of Korea Multimedia Society
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• v.17 no.7
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• pp.906-914
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• 2014

There are many studies to create realistic paint effects and the research area still has attracted attention in these days. However, the consideration for the characteristics of the real paint effects from the point of viewers is not enough. In this paper, we extract the important paint features and survey the importance values. Based on the survey results, we suggest a new paint system. The paint system utilizes the paint simulation that reflects viscoelasticity and mixing suggested by You et al. (2013) and proposes the paint rendering method that represents the details of a paint, a solvent, and pigments. We survey the quality of our results and prove that our paint system is superior to the previous studies.

• Korean Journal of Pharmacognosy
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• v.27 no.2
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• pp.155-158
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• 1996

The methanol extract of Albizzia julibrissin Durazz. (Leguminosae) was successively partitioned into dichloromethane, ethylacetate, butanol (BuOH) and water fractions, and the effects of the each solvent extract on catecholamine biosynthesis in PC12 cells were investigated. Among them, the BuOH fraction $(5{\mu}g/ml\;medium)$ showed 68.8% and 63.6% inhibition on dopamine and norepinephrine content in PC12 cells, respectively. Tyrosine hydroxylase (TH) activity was also reduced markedly by treatment of the BuOH fraction (41.8% inhibition at $5{\mu}g/ml$ in the medium). Each solvent fraction did not show cytotoxicity towards PC12 cells by trypan blue exclusion test. This result suggests that the BuOH fraction has an inhibitory effect on catecholamine biosynthesis by reducing TH activity in PC12 cells.

• Proceedings of the KIEE Conference
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• 1995.11a
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• pp.395-397
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• 1995

To investigate the effects of solvent extraction on electrical properties of LDPE, charge distribution, electrical conduction, and FT-IR experiments are carried out for three kinds of LDPE which are same for melt index (MI) and density. The effects of short chains for the charge distribution are quite different. For the electrical conduction, the electrical conduction mechanism remains unchanged, as the solvent extraction temperature is increased.

• Current Research on Agriculture and Life Sciences
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• v.31 no.1
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• pp.11-17
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• 2013

To investigate the effects of co-solvents on the morphology of nano-scale zein materials, zein solutions were electrospun with different co-solvent ratios of EtOH/$H_2O$. Different zein solution concentrations were used to study the effects of the zein content on the electrospun materials. The resulting electrospun materials were all characterized using field-emission scanning electron microscopy (FE-SEM) and transmission electron microscopy (TEM). The diameters of the electrospun nanoparticles and nanofibers were found to increase when increasing the EtOH ratio at certain zein concentrations. Furthermore, increasing the zein content changed the morphology of the electrospun materials from nanoparticles to nanofibers.