• Journal of the Korean Chemical Society
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• v.21 no.1
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• pp.53-59
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• 1977

A method of synthesizing $NaAlCO_3(OH)_2$ (Dawsonite) and $KAlCO_3(OH)_2$, was investigated by blowing $CO_2$ gas into sodium and potassium aluminate solutions. The reactions were accomplished at a temperature of 80 to $90^{\circ}C$, while $CO_2$ gas was blowing into the solutions which the molar ratios of $Na_2O/Al_2O_3,\;and\;K_2O/Al_2O_3$ were 6 to 8 and 8 to 10, respectively. It was observed that highly purified Dawsonite and $KAlCO_3(OH)_2$ are produced when Alumina is present in Boehmite at an equilibrium solid phase with a large amount of $HCO_3^-$ in the solutions. The rational formulas of Dawsonite and $KAlCO_3(OH)_2$synthesized under the conditions should be expressed as $NaAlO(OH)HCO_3\;and\;KAlO(OH)HCO_3$, respectively, by IR analysis. In addition, electron microscopic observation also indicated that Dawsonite in a fibrous crystal and $KAlCO_3(OH)_2$ in a needleshaped crystal.

• Journal of the Korean Chemical Society
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• v.28 no.6
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• pp.349-354
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• 1984

The relative viscosities and the osmotic coefficients of alkaline metal iodides (NaI, KI, RbI, CsI) in methanol, ethanol, dimethylsulfoxide (DMSO), and sulfolane (TMS) have been measured by Ubbelohde viscometer and vapor pressure osmometry at 45 ∼ $120^{\circ}C.$ The order of A and B coefficients in viscosity for alkaline metal iodides are MeOH > EtOH > TMS > DMSO, and TMS > EtOH > DMSO > MeOH. dB/dT values for the alkaline metal iodides are in the order of NaI > KI > RbI > CsI in the protic solvents, while those for the aprotic solvents are in the reverse order. The order of the osmotic coefficients for the alkaline metal iodides is EtOH > DMSO > MeOH > TMS.

• Journal of Korean Society of Environmental Engineers
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• v.27 no.3
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• pp.273-279
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• 2005

The degradation of o-chlorophenol(o-CP) in the presence of NaOH and the byproducts formed were investigated in a supercritical water(SCW) destruction process. The conversion of o-CP in the absence of NaOH was less than 20%, however it showed 100% conversion in the presence of NaOH(mole ratio[NaOH]/[o-CP] over than 2) with a residence time of less than 1 second. The formation of PAHs and the phenolic compounds formed were decreased in the presence of NaOH. The results revealed that the formation of byproducts during the destruction of o-CP in SCW was effected by the addition of NaOH. Phenol, cresols, chlorinated phenols, PAHs, p,p'-dihydroxybiphenyl and oxygenated polyaromatic compounds such as 1-indanone, dibenzofuran and dibenzo-p-dioxin were detected in both conditions(presence and absence of NaOH). At the same time, in the presence of NaOH, 2-ethylphenol, o-hydroxyacetophenone, hydroquinone, 4-allylphenol, 3-phenoxyphenol and 4,4'-oxybisphenol were also detected. The observed results suggest that the destruction of o-CP in SCW with NaOH occurs through a number of complicated reaction pathways. Dibenzofuran and dibenzo-p-dioxin were also detected during destruction of o-CP by SCW. The above observation suggests that there may be a common relationship between the thermal incineration process and SCW decomposition process.

• The Korean Journal of Food And Nutrition
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• v.30 no.1
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• pp.96-104
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• 2017

To obtain the immunomodulating polysaccharide from chaga mushroom (Inonotus obliquus sclerotia, IO), crude polysac- charide fractions (IO-M-CP and IO-CP, respectively) prepared from hot-water extract (IO-W) of I. obliquus by EtOH precipitation after MeOH reflux or not. After IO-W was re-dissolved in water followed by EtOH addition in the case without MeOH reflux, EtOH mixture was fractionated into EtOH-soluble (IO-E) and crude polysaccharide (IO-CP). In the meanwhile, MeOH-soluble fraction (IO-M) was separated from IO-W after MeOH reflux. The residue was dissolved in water and was added by EtOH, and then EtOH mixture was also fractionation into EtOH-soluble (IO-M-E) and crude polysaccharide (IO-M-CP). As a result of the macrophage stimulating activity of these fractions, IO-CP and IO-M-CP showed significantly increased cell proliferation and cytokines production than IO-W. Particularly, IO-M-CP promotes the production of IL-12 more than IO-CP. In the splenocytes proliferating activity and intestinal immune system modulating activity through Peyer's patch, both of 2 crude polysaccharide fractions were significantly promoted in cell proliferation and cytokines production than IO-W, and IO-M-CP was more potent than IO-CP in IL-2 production from splenocytes and GM-CSF production ($10{\mu}g/mL$) in Peyer's patch cells. In addition, immunomodulating polysaccharide fractions (IO-M-CP and IO-CP) prepared from IO-W by EtOH precipitation with or without EtOH reflux showed no significant difference in the chemical composition and component sugar. These results suggested that MeOH reflux might exclude low-molecular weight materials from IO-W and consequently increase the immunomodulating activity of IO-M-CP. Therefore, it was confirmed that immunomodulation of polysaccharide prepared from hot-water extract of chaga mushroom was enhanced by fractionation including MeOH reflux and EtOH precipitation.

• Journal of the Korean Society of Groundwater Environment
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• v.5 no.4
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• pp.171-176
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• 1998

The effect of non-ionic surfactants added by hydroxides was studied to wash HOCs-contaminated soil. The kinds and concentrations of additives-mixed surfactants suitable for the soil washing were found. The effects of temperature on the soil washing were analyzed and the relations of HLB and cloud point were estabilished. As the base strength was increased, the washing efficiency was increased : NaOH＞KOH＞ Mg(OH)$_2$>Al(OH)$_3$. Washing efficiency was not enhanced by Al(OH)$_3$for coagulation effect. When NaOH was added to POE$\_$5/ washing efficiencies by 0.01 M and 0.1 M solutions were increased to 62.5% and 67.3%, respectively. At 1 M of NaOH washing efficiency was decreased to 4.2%. The Optimum concentration ratio of mixed surfactant ［POE$\_$5//POE$\_$14/] was 1.8%/1.2% without additives. But optimum concentration ratio of surfactants was changed to 1.2%/1.8% with 0.01 M of NaOH addition. The surface tensions and CMCs of mixed surfactant added by NaOH solutions were investigated. The addition of NaOH reduces the surface tension of more hydrophobic surfactants. The nonionic surfactant of higher HLB showed highed cloud point.

• Applied Chemistry for Engineering
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• v.10 no.8
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• pp.1192-1199
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• 1999

The morphology changes of cadmium hydroxide into ${\gamma}$ phase by eletrolytes were carried out to improve the high rate charge and discharge efficiency of pasted cadmium electrodes. KOH solutions with different concentrations of NaOH were used as eletrolytes. It was found that the utilization of active material of cadmium electrode was the best in an electrolyte with 1.82 M NaOH. The amount of ${\gamma}-Cd(OH)_2$ increased in proportion to the concentration of NaOH. The surface area measurement showed that an active material which contained mainly ${\gamma}-Cd(OH)_2$ had a higher specific surface area than an active material of ${\beta}-Cd(OH)_2$. In a sealed cell, the discharge capacity was improved at high rate charge and discharge (1.0 C, 2.0 C) by using an electrolyte with NaOH. Furthermore, these improved performances were maintained up to 500 cycles at 1.0 C rate charge and discharge cycles.

• Journal of Life Science
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• v.26 no.8
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• pp.948-954
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• 2016

We investigated the flavonoid and phenol contents and antioxidant effect of wine by-product extract. Antioxidant effects were measured with 1,1-diphenyl-2-picryhydrazyl (DPPH) and 2.2'-azino-bis(3-ethylbenothiazoline-6-sulfonic acid) diammonium salt radical cation (ABTS+) assays. Cellular reactive oxygen species (ROS) were measured with the dichlorofluorescein-diacetate (DCFH-DA) assay. The flavonoid and phenol contents of the methanol (MeOH) extract were greater than those of the acetone+methylene chloride (A+M) extract. Among fractions, the 85% aqueous methanol (85% aq. MeOH) fraction contained the highest flavonoid contents, while the n-BuOH fraction had more phenol contents. In the DPPH and ABTS assays, the MeOH extract showed a scavenging effect greater than that of the A+M extract (p<0.05). The n-BuOH fraction (0.5 mg/ml concentrations) showed scavenging effects of 72% and 92%, respectively, in the DPPH and ABTS assays (p<0.05). However, the 85% aq. MeOH fraction showed a 90% scavenging effect in the DPPH assay only. In 120 min ROS production assay, all tested fractions dose-dependently decreased cellular ROS production induced by H₂O₂ in comparison with that produced by exposure to the extract-free control. The MeOH extract showed a higher sinhibitory effect on cellular ROS producing than that of the A+M extract at all concentrations tested. Treatment with the n-BuOH fraction (0.1 mg/ml concentrations) inhibited cellular ROS production by 60%. These results indicate that the n-BuOH fraction of wine by-product extract inhibited cellular oxidation and may contain valuable bioactive compounds such as flavonoids and phenols.

• Journal of Life Science
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• v.29 no.3
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• pp.337-344
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• 2019

The free radical scavenging, cytotoxic effects, and flavonoid content of fractions from Lycopus lucidus Turcz leaves were here investigated. The flavonoid contents of 85% methanol (MeOH) and n-butanol (BuOH) fractions of the leaves were 41.5 mg/g and 77.2 mg/g, respectively. In DPPH and ABTs+ assays, 85% MeOH and n-BuOH fractions from the L. lucidus Turcz leaves had a greater scavenging effect (p<0.05). The n-BuOH fraction (0.5 mg/ml concentration) had scavenging effects of 88% and 92% in the DPPH and ABTs+ assays, respectively (p<0.05). Cell viability tests showed that treatment with L. lucidus Turcz leaf fractions caused cytotoxicity in the growth of AGS, HT-29, and HT-1080 cancer cells. Of the different fractions, the 85% MeOH sample displayed the highest cytotoxic activity; the $IC_{50}$ values of this fraction against AGS, HT-1080, and HT-29 cancer cells were 0.03 mg/ml, 0.14 mg/ml, and 0.16 mg/ml, respectively. These biological results indicate that the n-BuOH fraction was more effective in anti-oxidant activity while the 85% MeOH fraction was stronger in cytotoxic effects, and they suggest that these two fractions from L. lucidus Turcz leaves may contain valuable bioactive compounds, such as flavonoids.

• Applied Chemistry for Engineering
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• v.16 no.3
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• pp.312-316
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• 2005

Adsorption characteristics of $CO_2$ on activated carbons were evaluated using dynamic adsorption method in a fixed bed with acid treatment, LiOH impregnation and water vapor supply. Physical and chemical properties of the activated carbons were measured using SEM, EDS, nitrogen adsorption, FTIR and XRD. Nitric acid treatment led to the decrease in BET surface area and the increase in oxygen content of virgin activated carbon, and it produced a new functional group that included nitrogen. For the reduction of BET surface area by LiOH impregnation, the nitric acid treated activated carbon (NAC) was less than the virgin activated carbon (AC). Large particles of LiOH were present on the carbon surface when the content of LiOH was over 2 wt%. The adsorbed amount of $CO_2$ on activated carbon in a fixed bed increased with the acid treatment, LiOH impregnation and water vapor supply. The XRD results indicated that LiOH was converted to $Li_2CO_3$ after the adsorption of $CO_2$ on LiOH precursor.

• Food Science and Preservation
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• v.18 no.1
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• pp.65-71
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• 2011

We explored the effect of extracts of dried Platycodon grandiflorum on production of reactive oxygen species (ROS), glutathione (GSH) and nitric oxide (NO). To determine antioxidant activity in the presence of $H_2O_2$-induced oxidative stress, DCFH-DA (dichlorodihydrofluorescin diacetate) assay was employed. Acetone/methylene chloride (A+M) and methanolic (MeOH) extracts of P. grandiflorum reduced intracellular ROS levels. Of the various tested fractions, n-BuOH fraction showed the highest protective effect in terms of lipid peroxide production. Total GSH levels were measured after treatment of HT1080 cells with the A+M and MeOH extracts, and other solvent fractions, at various concentration. The A+M extacts and 85% (v/v) aqueous MeOH fraction significantly increased GSH levels (p<0.05). When lipopolysaccharide (LPS)-induced NO production was evaluated, all tested crude extracts, and fractions thereof, significantly reduced NO production (p<0.05), and the n-BuOH and 85% (v/v) aqueous MeOH fractions (at 0.05 mg/mL) showed the strongest inhibitory effects. The results showed that the n-BuOH fraction inhibited both cellular oxidation and NO production, and this fraction may thus contain valuable active compounds.