• Journal of Korean Society on Water Environment
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• v.23 no.5
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• pp.659-664
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• 2007

The objective of this study is to evaluate the detoxification method for the endocrine disrupting chemicals by manganese oxide. Manganese coated sand and bisphenol-A (BPA) was used as the reactive medium and the contaminant. Results showed that manganese oxide effectively degrades BPA by oxidative coupling reaction. The nonlinear oxidative coupling reaction orders were obtained for BPA and oxide, respectively. The reaction rate of BPA decreased as initial BPA concentration increased, as oxide loading decreased and as pH increased. The higher ionic strength, the higher reaction rate was observed. Divalent cations were adsorbed on the oxide surfaces, resulting in the decreased degradation rate of BPA.

• YAKHAK HOEJI
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• v.32 no.4
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• pp.234-238
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• 1988

Proliposome of Sudan IV was prepared according to Payne et al. and evaluated for it's size distribution, surface characteristics and conversion to liposome in aqueous medium. The manufacturing procedures for proliposomes involve the coating of phospholipid solution with Sudan IV on the surface of sorbitol particle in rotary vacuum evaporator. As a result, dry, free flowing and stable proliposome was obtained and multi-lamellar liposome of sudan IV was formed spontaneously when water were added to this. Proliposomes were expected as a probable answer for the physical instability of conventional liposomes.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2001.09a
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• pp.115-119
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• 2001

Contaminant retardation factor is derived from the colloidal and contaminant transport equations for a four-phase porous medium: an aqueous phase, two mobile colloidal phases, and a solid matrix. It is assumed that the contaminant sorption to solid matrix and colloidal particles and the colloidal deposition on solid matrix follow the linear isotherms. The behavior of the contaminant retardation factor in response to the change of model parameters is examined employing the experimental data of Magee et al. (1991) and Jenkins and Lion (1993). In the four-phase system, the contaminant retardation factor is determined by both the contaminant association with solid matrix and colloidal particles and the colloidal deposition on solid matrix. The contaminant mobility is enhanced when the affinity of contaminants to mobile colloids increases. In addition, as the affinity of colloids to solid matrix decreases, the contaminant mobility increases.

• Fashion & Textile Research Journal
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• v.5 no.1
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• pp.82-88
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• 2003

This study was carried out to investigate combination dyeing of the cationized cotton with natural colorants extracted from Gardenia and Sappan wood extract using methanol. To improve dyeing properties of cotton with natural dye, cotton fabric was preheated with cationizing agent containing chlorohydrine group in aqueous solution of sodium hydroxide. On the whole the various medium colors were developed by repeat dyeing with different colorants after dyeing with one colorant in case of natural dyeing, In this study, however in order to obtain various colors on cationized cotton fabrics with natural dyes, pre-mordanting and combination dyeing were carried out. The various colors were obtained according to various metal compounds for pre-mordants and various mixing portion of Gardenia and Sappan wood. Metal compounds containing alum, copper and iron were used for pre-mordants.

• Bulletin of the Korean Chemical Society
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• v.35 no.7
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• pp.2029-2032
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• 2014

Magnetically nano-$CoFe_2O_4$ efficiently catalyzes oxidation of primary and secondary benzylic and aliphatic alcohols to give the corresponding carbonyl products in good yields. The reactions were carried out in an aqueous medium at room temperature in the presence of oxone (potassium hydrogen monopersulfate) as an oxidant. In addition, the catalysts could be reused up to 6 runs without significant loss of activities. Catalyst was characterized by SEM, XRD and IR.

• Archives of Pharmacal Research
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• v.17 no.4
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• pp.240-243
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• 1994

Release rates of flurbiprofen from transdermal gels made of poloxamer 407 were evaluated using a membraneless diffusion cell in order to study the effects of formulation variables on flurbiprofen release such as poloxamer 407 (17.5-25%) drug (0.1-1.0%), ethanol (10-20%), PG or PEF 300 (5-15%) concentrations and gel pH(3-7). Isopropyl myristate was employed as a receptor medium for the drug released from the gel. The diffusion coefficient of flurbiprofen decreased linearly as the amount of poloxamer 407 and the drug in the gel increased. The release rate of flurbiprofen was gel increased. The The addition of more ethanol in the gel increased the drug release, resulting from the increase of the thermodynamic activity of the drug in the aqueous phase of the gel. However, the concentration effects of PG and PEG 300 on the release rate of flurbiprofen were negligible over the concentration range used.

• Journal of Photoscience
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• v.12 no.3
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• pp.143-147
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• 2005

The simultaneous determination of harman, harmaline and norharman has been described using synchronous fluorescence technique. The method has been based on their natural fluorescence. It is difficult to analyze and determine their contents by conventional fluorescence method because of their similar molecular structures. The synchronous spectrum, maintaining a constant wavelength difference of ${\Delta}{\lambda}=185nm$ between the excitation and emission monochromators, was selected as optimum to perform the determination. The method was also performed in aqueous medium at pH 4.0 and in presence of sodium dodecyl sulfate (SDS), $1{\times}10^{-5}M$. Under the optimum conditions, each analyte has the linear determination range of $1{\times}10^{-7}M-\;1{\times}10^{-4}M$.

• Journal of the Korean Chemical Society
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• v.12 no.3
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• pp.128-137
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• 1968

In the oligomerization of p-aminophenol by the catalytic action of Fe-EDTA complex in the aqueous medium, the mixed complex intermediate, Fe-EDTA-M type, is considered to be formed, from which active radicals of the monomer are produced. In this system, polymerization is presumed to proceed as follows: Free radical formation ${\to}$ Coupling ${\to}$ Activation ${\to}$ Coupling, and so on. In this study, the form of the monomer and coordination state in the mixed complex, the catalytic action of Fe-EDTA the complex, the reaction mechanism, and the structure of the oligomers are discussed.

• Textile Coloration and Finishing
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• v.7 no.2
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• pp.47-54
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• 1995

Safflower is natural red dye largely used for dyeing on cotton. It contains yellowish safflower yellow and reddish carthamin, whose constitution is known. Safflower yellow is water-soluble dye and carthamin is solved in alkaline condition. Carthamon obtained by adding acidic solution to a carthamin shows the original hue of safflower. In present study, the dyeing behavior of natural dye known as safflower are examined in an aqueous acidic medium by use of the different dyeing methods such as traditional, modern and purifide-powder method. The relationship between the dye-uptake of cotton fabric investigated by the three methods and the various dyeing conditions is discussed.

• Proceedings of the Korean Vacuum Society Conference
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• 2012.02a
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• pp.529-529
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• 2012

Dispersion of carbon nanotubes in biocompatible media are of particular interest for diverse biomedical and nanomedicine applications. Various biomolecules and biopolymers such as DNA, proteins, poly L-lysine, starch, gelatin, steroid biosurfactants, and chitosan have shown capability for the effective dispersion of carbon nanotubes in water. Chitosan has demonstrated capacity for effective dispersion of single-walled carbon nanotubes (SWCNTs) in acidic medium and it also showed tendency to preferentially disperse smaller diameter nanotubes. Chemical functionalizations of chitosan enable its solubility in neutral pH water by reducing the intra and inter molecular hydrogen bonding. Herein, we present a neutral pH water soluble chitosan derivative, chitosan-hydroxyphenyl acetamide (CHPA), obtained by functionalizing the amino groups of chitosan with 4-hydroxyphenyl acetic acid, as an efficient biocompatible dispersant for debundling and solubilization of SWNTs in neutral aqueous solutions. Various process conditions for individual dispersion of SWCNTs are analyzed based on optical absorption and Raman spectroscopy.