• Applied Chemistry for Engineering
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• v.10 no.2
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• pp.206-211
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• 1999

Mixed-bed ion exchange performance was studied experimentally with variations of cation to anion resin ratio, resin weight and temperature at ultralow sodium chloride solution concentrations of less than $1.0{\times}10^{-4}M$. Analyzing the effluent concentration histories the performance test was examined as a function of tested solution volume for a laboratory-scale continuous flow column until both the cation and anion-exchange resins were exhausted. Initial leakage was observed for both cation and anion breakthrough curves, but serious at cation breakthrough curve because of low selectivity coefficient. The slope of breakthrough curve was affected by selectivity coefficient and temperature. The slope of anion breakthrough curve was steep because of the large selectivity coefficient, and ion exchange rates increased as temperature increased. The temperature effect decreased as the total volume was increased or as the resins were exhausted.

• Journal of Environmental Science International
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• v.18 no.6
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• pp.595-601
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• 2009

The effects of the cation-to-anion resin ratio and bed depth on ion exchange performance of mixed-bed were studied at ultralow solution concentration. Breakthrough curves were experimentally obtained for NaCI solution as functions of resin ratio and bed depth. The bed depth affects the pattern of the sodium breakthrough curve but not the chloride breakthrough curve in beds because of the selectivity difference. Resin selectivity determines the shape of breakthrough curves, Some sodium and chloride breakthrough curves crossed at a point as a function of resin ratio. The lower cation-to-anion resin ratio showed the higher effluent concentration or treated volume of the crossover point regardless of the total resin weight.

• Membrane and Water Treatment
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• v.8 no.4
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• pp.369-380
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• 2017

Performance evaluation of four commercially available tubular membranes (AFC 80, AFC 30, PU 608, ES 404) was accomplished in self-assembled membrane testing unit. Effects of varying transmembrane pressure, feed concentration and anion type were investigated. Aqueous solutions of salts such as calcium chloride, calcium sulfate, tin chloride and tin sulfate were prepared for this study. It was noted that the investigated parameters e.g., pressure and concentration had significant effects on membrane's performance. Nevertheless, anion type effectively played its role in the rejection of salts since salt having SO4-2 anions had a better rejection than the salts containing Cl-1. It is observed that rejection was dominated by Donnon exclusion for strongly charged nanofiltration membranes whereas for weakly charged ultrafiltration membranes, size exclusion was the key mechanism to reject the ions.

• Bulletin of the Korean Chemical Society
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• v.13 no.1
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• pp.37-41
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• 1992

The reactions of nitrous acid with hydrogen peroxide in acidic aqueous solution in the presence of several added anions have been studied at $0^{\circ}C$ and pH 2-4 to investigate the nucleophilic catalysis of these anions. From the dependence of reaction rates on the anion concentrations, significant catalytic effects were found for $Cl^-,\;Br^-,\;SCN^-$, in order of effect $SCN^-\;{\approx}\;Br^->Cl^-$, while no observable effect was found for ${ClO_4}^-$ and ${NO_3}^-$. These results support O-nitrosation reaction is the rate-determining step and NOX formed in the presence of an anion ($X^-$) also acts as a nitrosating agent and accelerates the overall reaction rate. The order of reactivity was found to be NOCl>NOBr>NOSCN, which is consistent with the results of N-nitrosation and S-nitrosation reactions.

• Proceedings of the PSK Conference
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• 2003.10b
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• pp.155.1-155.1
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• 2003

Polyphenol QGR (quercetin 3-O-beta-(2"-galloyl)-rhamnopyranoside) was isolated from Persicaria lapathifolia (Polygonaceae). In this study, we investigated inhibitory effects of QGR and its building blocks (quercitrin, quercetin and gallic acid) on superoxide anion and NO productions in unopsonized zymosan-stimulated murine macrophages Raw264.7. QGR and quercetin showed potent inhibitory effects on unopsonized zymosan-induced superoxide anion production with IC50 values of 3.2 uM and 4.8 uM, respectively. (omitted)

• Journal of Society of Preventive Korean Medicine
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• v.9 no.2
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• pp.93-106
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• 2005

A survey was performed for 2 weeks in October 2004 in order to examine the effects and changes of far infrared and anion of office workers aged 40 and older before and after wearing the underwear. In the survey, questionnaires and photoplethysmography were used to measure the difference between the two tests conducted with one week interval. The findings could be summed up as follows: 1. There was no statistically significant difference in changes of vascular aging points and photoplethysmogram wave form before and after wearing the far infrared and anion underwear but the points showed the increasing tendency(p>0.05). 2. A statistically significant difference was confirmed since the total points of each item in the questionnaires increased after wearing the underwear(p<0.001). 3. In connection with the systemic symptoms, a significant difference was found with increased points in all items except for no. 6 after wearing the underwear(p<0.05). 4. With regard to the difference before and after wearing the underwear depending on the Kidney symptoms, there was a significant difference with increased points in all items except for item no. 1 after wearing the underwear(p<0.05). In conclusion, to put on the underwear with effect of far infrared and anion is believed to smooth metabolism and blood circulation, contributing by thus to promoting health and preventing disease. Further studies with wider sampling of subjects are requested to diversify and refine the findings from this sectional study.

• 한국전기화학회:학술대회논문집
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• 1999.10a
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• pp.39-39
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• 1999

• 한국전기화학회:학술대회논문집
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• 2002.04a
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• pp.27-27
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• 2002

• 한국전기화학회:학술대회논문집
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• 2004.10a
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• pp.11-11
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• 2004

• 한국전기화학회:학술대회논문집
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• 1999.04a
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• pp.42-42
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• 1999