• Environmental Sciences Bulletin of The Korean Environmental Sciences Society
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• v.2 no.1
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• pp.79-84
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• 1998

The rates of absorption of carbon dioxide into aqueous solutions of 2-amino-2-methyl-1-propanol (AMP) were measured using a semibatch stirred vessel with a plane gas-liquid interface at $25^{\circ}C.$ The absorption rates under the fast reaction regime were analysed using chemical absorption theory. The reaction was found to be first order with respect to both $CO_2$ and the amine.

• Journal of Biomedical Engineering Research
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• v.14 no.3
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• pp.227-234
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• 1993

Hemofilter was optimally designed and manufactured using polysulfone hollow fiber mem- brane with surface area of 0.6mE Molecular weight cut-off of the hemofilter was measured with polyethylene glycol and dextran aqueous solutions of various molecular weights and it was ranged from 9,500 to 38,900. Ultrafiltration rates were measured with pure water in a static system and flowing system. The clearance of urea, creatinlne, and vitamine BIB were measured using aqueous solutions.

• Journal of Plant Biology
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• v.18 no.4
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• pp.155-160
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• 1975

Growth responses of lettuce seeds germinated in aqueous solutions of $SO_2$ were investigated for mode of action studies of this gas. The concentration and pH of $SO_2$ solution greatly affected the growth of germinating seeds. Root growth was more sensitive to $SO_2$ than hypocotyl growth. The sensitivity of total seedling growth lay between root and hypocotyl growth. Growth inhibition of germinating seeds appeared more serioius when $SO_2$ was added during the early stage of germination.

• Proceedings of the Membrane Society of Korea Conference
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• 1994.10a
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• pp.8-11
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• 1994

Disposal of hazardous ions in the aqueous streams is a significant industrial waste problem.. Waste streams from electronics, electroplating, and photographic industries contain metal ions such as copper, nickel, zinc, chromium(IV), cadmium, aluminum, silver, and gold, amongst others in various aqueous solutions such as sulfates, chlorides, fluorocarbons, and cyanides. Typical plating solutions having similar compositions are listed in Table 1. Spent process streams in catalyst manufacturing facilities also contain precious metals such as Ag, Pt, and Pd. Developing an effective recovery process of these metal ions for reuse is important.

• Journal of Environmental Science International
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• v.2 no.1
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• pp.79-84
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• 1993

The rates of absorption of carbon dioxide into aqueous solutions of 2-amino-2-methyl-1 propanol (AMP) were measured using a semibatch stirred vessel with a plane gas-liquid interface at $25^{\circ}C$. The absorption rates under the fast reaction regime were analysed using chemical absorption theory. The reaction was found to be first order with respect to both $CO_2$ and the amine.

• Journal of Pharmaceutical Investigation
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• v.16 no.3
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• pp.101-105
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• 1986

The changes of water absorption and surface area of polydimethylsiloxane-5-fluorouracil devices containing different water soluble additives such as sodium chloride, glycerine, poly-propylene glycol(PPG 400), and polyethylene oxide(PEO 400, 400 and 2000) were investigated. It was confirmed that carriers controlled water absorption and swelling of the devices in the aqueous solutions. The water absorption and the swelling were affected by the osmotic pressure and ionic strength of the aqueous solutions.

• Bulletin of the Korean Chemical Society
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• v.6 no.3
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• pp.149-152
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• 1985

Spectrophotometric and spectrofluorimetric methods of analysis were conducted in dilute aqueous solutions of methylene blue and tetraphenylborate. The formation of double ion-pair was confirmed and its overall formation constant, ${\Delta}H^{\circ}$, and ${\Delta}S^{\circ}$ were obtained. The irradiation with wavelengths over visible region resulted in bleaching the mixed solution. The bleaching reaction was also proceeded at $55^{\circ}C$. The reactions of the double ion-pair were briefly discussed.

• Bulletin of the Korean Chemical Society
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• v.19 no.8
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• pp.825-830
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• 1998

The electrocatalytic reduction of dioxygen by Co(TTFP)(Y)2 {Y=H2O or HO-} is investigated by cyclic voltammetry, spectroelectrochemistry, hydrodynamic voltammetry at a glassy carbon electrode in dioxygen-saturated aqueous solutions. Electrocatalytic reduction of dioxygen by CoⅡ(TTFP)(Y)2 establishes a pathway of 2e- reduction to form hydrogen peroxide, and then the generated hydrogen peroxide is reduced to water by CoⅠ(TTFP)(Y)2 at more negative potential. CoⅡ(TTFP)(Y)2 may bind dioxygen to produce the adduct complex [CoⅡ-O2 or CoⅢ-O2] which exhibits a Soret band at 411 nm and Q band at 531 nm.

• Bulletin of the Korean Chemical Society
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• v.10 no.2
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• pp.148-151
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• 1989

The hydrophobic interaction between tetraphenylborate (TPB$^-$) or tetrakis (4-fluorophenyl)borate (TFB$^-$) and crystal violet has been investigated in aqueous solutions by absorption spectrophotometry. Both of the anions promote the aggregation of the ion pairs formed between crystal violet and TPB$^-$ or TFB$^-$. When crystal violet and borate anion are nearly equimolar, insoluble floating aggregates can be observed. Based on the relative absorbance of H and J bands and on the effect of TX-100, TFB$^-$ is found to be more hydrophobic than TPB$^-$.

• Bulletin of the Korean Chemical Society
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• v.13 no.3
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• pp.259-265
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• 1992

Cyclic voltammetric behavior of symmetric (dimethyl, diheptyl, dioctyl, dibenzyl) and asymmetric (methyloctyl, methyldodecyl, methylbenzyl) viologens was investigated in homogeneous aqueous solution and sodium dodecyl sulfate (SDS) micellar media. In SDS-free 0.1 M NaCl solutions, the reduction potential is less negative as the chain length of alkyl substituent is longer. This is due to the stabilization of the reduced cationic radical and neutral form of viologen by adsorption on electrode surface. The adsorbed species show the "aging-effect". With the exceptions of methyldodecyl viologen and methylbenzyl viologen, the viologens show strong tendency of conproportionation reaction between viologen dications and neutral forms. In cases of methyldodecyl viologen and methylbenzyl viologen, the conproportionation reaction is kinetically disfavored, though it is thermodynamically favorable. SDS micelles dissolve the adsorbed species and the viologens exhibit two reversible redox processes in SDS micellar solutions. The reduction potentials of viologens in SDS micellar solutions depend little on the length of alkyl chain. Benzyl-substituted viologens are more easily reduced than the alkyl substituted viologens, presumably due to electron-withdrawing character of benzyl group.