• Bulletin of the Korean Chemical Society
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• v.31 no.9
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• pp.2557-2560
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• 2010

To assay for antioxidant capacity of natural products considered important in producing human health benefits, a practical and economical method using pellet techniques was developed. A standard visualizing reagent, 1,1diphenyl-2-picryl-hydrazyl (DPPH), was mixed with a water-miscible polyvinyl alcohol (PVA), serving as a solid phase support for the DPPH reagent. A DPPH pellet was prepared by dropping a small volume of the DPPH solution onto PET film, and drying in an oven. The PVA-based DPPH pellet was dissolved into water, in which the water-miscible PVA plays as a non-ionic surfactant to help the DPPH reagent to be dissolved into the solvent. Using the DPPH assay, the antioxidant capacity of water-soluble extracts of black soybean, barley, green tea, and green gram was examined. Among the natural products tested, green tea showed the highest antioxidant capacity. This PVA-based DPPH antioxidant assay can be further applied in the natural food, raw plant material, and health product inspection field.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2006.04a
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• pp.949-954
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• 2006

The purpose of this paper is to investigate the stability of tapered columns with clamped one end and carrying a tip mass of rotatory inertia with translational elastic support at the other end. The linearly tapered columns with the solid rectangular cross-section is adopted as the column taper. The differential equation governing free vibrations of such Beck columns is derived using the Bernoulli-Euler beam theory. Both the divergence and flutter critical loads are calculated from the load-frequency curves which are obtained by solving the differential equation. The critical loads are presented as functions of various non-dimensional system parameters: the taper type, the subtangential parameter, mass ratio and spring stiffness.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.30 no.1
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• pp.1-6
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• 2004

Although the cosmetic market continuously develops in korea, the foreign product occupies more and more its market3hare in korea. For the future of our industry, institutional support for the ‘functional cosmetics’ (Cosmeceuticals) development should be secured and export infrastructure should be more solid. This paper examines recent trend in cosmetics market (home and foreign) and identifies barriers for the development of cosmetic market. In conclusion, we present several policy strategies for the development of its market.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.12 no.sup1
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• pp.53-61
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• 2009

The mainstay in the management of mild to moderately dehydrated children is fast rehydration by using hypotonic ORS (oral rehydration solution) and complete resumption of normal diet, including lactose-containing formula after 4 hours rehydration. Since the majority of young children with uncomplicated acute diarrhea will tolerate large amounts of undiluted non-human milk, withholding food and milk from children during diarrhea is not recommended anymore, regarding time to resolution and diarrhea control. In addition, routine dilution of milk and routine use of lactose-free formula are not necessary after fast ORS therapy. Breastfed infants and children fed with solid foods may safely continue receiving their usual diets during diarrhea instead of gradual reintroduction of feeding. However, young infants or children with severe diarrhea or malnutrition should be carefully treated under supervision if fed with lactose containing, non-human milk exclusively.

• Textile Coloration and Finishing
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• v.26 no.2
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• pp.143-149
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• 2014

The designed dye material, namely 2-(4-(9H-carbazol-9-yl)benzylidene) compound, was synthesized. After the reaction, the solid was filtered and purified by recrystalization with acetone/water. To confirm and analyze its synthesis and structural formation, the single crystal was prepared and its measurement was carried out. A yellow needle crystal of $C_{22}H_{13}N_3$ were made on a Rigaku R-AXIS RAPID diffractometer using graphite monochromated CuK${\alpha}$ radiation. All details were suggested and introduced to support and communicate this study.

• Journal of the Korea Safety Management & Science
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• v.1 no.1
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• pp.259-272
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• 1999

In order to enhance the selectivity, productivity and yield of methyl fructoside, which was synthesized by enzymatic glycosylation of sucrose and methanol solution, controlling of surface property of solid support using different immobilization procedures optimized microenvironment of immobilized invertase. Silanization and polyethylene imine coating methods were adopted to give a hydrophobic and hydrophilic environment of immobilized invertase. As a result, polyethyleneimine coating method gave higher loading of enzyme, effective activity, and relative activity than silanization method, because it brought on increasing the functional density of amino group and enhancing the conservation of activity by regulating of hydrophilicity. And then, hydrophilic environment was possible to restraint the assessing of methyl fructoside molecule, which was more hydrophobic than sucrose, fructose, and glucose molecule in the reaction mixture, into .the active site of immobilizedinvertase. Consequently, hydrophilic microenvironment of immobilized invertase by polyethyleneimine coating obtained higher yield and productivity with increasing conversion than silanized and native invertase. Thus, this procedure optimized the microenvironment of immobilized invertase suitable for the enzymatic synthesis of methyl fructoside.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 2002.05a
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• pp.266-271
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• 2002

We propose a hardware accelerated voxelization method for various 3D object model such as surface models, solid models, and volumetric CSG models. The algorithm utilizes the stencil buffer that is one of modern Open히 graphics hardware features. The stencil buffer is originally used to restrict drawing to certain portions of the screen. The volumetric representations of given 3D objects are constructed slice-by-slice. For each slice, the algorithm restricts the drawing areas constructed inner region of 3D objects using the stencil buffer, and generates slices of the volumetric representation for target objects. As a result, we can provide volume graphics support for various engineering applications such as multi-axis machining simulation, collision detection and finite element analysis.

• Journal of Powder Materials
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• v.6 no.1
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• pp.18-35
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• 1999

Phase equilibria in the system Si3N4-TiC-TiCxN1-x-C-N were determined by thermodynamic calculations (CALPHAD-method). The reaction peaction paths for Si3N4-TiC and SiC-TiC composites in the Ti-Si-C-n system were simulated at I bar N2-pressure and varying terpreatures. At a temperature of 1923 K two tie-triangles (TiC0.34N0.66+SiC+C and TiC0.13N0.87+SiC+Si3N4) and two 2-phase fieds (TiCxN1-x+SiC; 0.13

• YAKHAK HOEJI
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• v.34 no.1
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• pp.11-14
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• 1990

$NH_2-terminal$ amino acid sequence analysis of monoclonal antibody is very important to identify gene family and diversities of antigen-antibody recognition. When we used the PVDF (Polyvinylidene difluoride) membrane blotting method, we could easily analyze $NH_2-terminal$ sequence of monoclonal-antibody which specifically binds to phosphatidylinositol 4,5-biphosphate. PVDF membrane is an ideal solid-phase support for sequence analysis, especially when used with electroblotting method. This method is superior to continual method and will be applied to the sequence analysis of picomole quantities of proteins by gel electrophoresis.

• Bulletin of the Korean Chemical Society
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• v.32 no.3
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• pp.899-904
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• 2011

A series of 5-indolylpyrimido[4,5-d]pyrimidinones (4a-h) were obtained by multi-component reaction of 3-formylindole (1), thiobarbituric acid/barbituric acid (2) and thiourea/urea (3) under microwave irradiation in dry media. Secondly, grinding together neat reactants also gave the titled compounds in good yields. All the synthesized compounds have been characterized on the basis of elemental analyses and spectral data (IR, $^1H$ NMR and Mass). Representative compounds were also evaluated for their antimicrobial activity against Rhizopus stolonifer, Fusarium oxysporum, Escherichia coli, and Pseudomonas aeruginosa at different concentrations. Some of the compounds showed promising activity.