• Asian-Australasian Journal of Animal Sciences
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• v.19 no.10
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• pp.1490-1495
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• 2006

The purpose of this research was to develop an optimum composition model for a new synbiotic fermented dairy product with high probiotic cell counts, and to experimentally verify this model. The optimum composition model indicated the growth promoter ratio that could provide the highest growth rate for probiotics in this fermented product. Different levels of growth promoters were first blended with milk to improve the growth rates of probiotics, and the optimum composition model was determined. The probiotic viabilities and chemical properties were analyzed for the samples made using the optimal formula. The optimal combination of the growth promoters for the synbiotic fermented milk product was 1.12% peptides, 3% fructooligosaccharides (FOS), and 1.87% isomaltooligosaccharides (IMO). A product manufactured according to the formula of the optimum model was analyzed, showing that the model was effective in improving the viability of both Lactobacillus spp. and Bifidobacterium spp.

• YAKHAK HOEJI
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• v.42 no.2
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• pp.140-143
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• 1998

From the methanol extract of the whole part of Sagittaria trifolia ergosterol peroxide, icariside D2. Thalictoside and 4-nitrophenyl $\{beta}$-D-glucopyranoside wer e isolated and their structures were identified by the physico-chemical and spectral data. This is the first report of these compounds from S. trifolia.

• Bulletin of the Korean Chemical Society
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• v.32 no.11
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• pp.3963-3966
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• 2011

A series of pyranopyrazoles, was efficiently synthesized via one-pot, four component reaction of ethyl acetoacetate, hydrazine hydrate, aldehydes and malononitrile in the presence of catalytic amount silicotungstic acid under solvent free condition. NOE experiments confirmed that the product exist exclusively in the 2H form. The present protocol offers the advantages of clean reaction, short reaction time, high yield, easy purification and economic availability of the catalyst.

• Journal of the Korean Ceramic Society
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• v.55 no.3
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• pp.299-306
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• 2018

In order to improve the hardness of commercial bone china, we suggested a chemical strengthening process and new glaze for its process. New glaze contained about two times more $Na_2O$ and $Al_2O_3$ and had a higher transition temperature than that of commercial frit. Chemical strengthening enhanced the hardness of the new glaze-coated bone china by over 30% compared to that of commercial product. The change of glaze composition influenced potassium ion diffusion distance and depth of strengthened layer during chemical treatment. After chemical strengthening of new glaze-coated bone china, the residual compressive stress inside the glaze was measured and found to be greater than 160 MPa.

• Korean Chemical Engineering Research
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• v.44 no.3
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• pp.289-293
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• 2006

In the CMSMPR (continuous mixed suspension mixed product removal)system, the effect of temperature and RPM on the CSD (crystal size distribution) in the calcium carbonate process was investigated. In the steady state operation, the change of solution pH was small. At the low temperature and below 300 RPM, volume mean size change of calcium carbonate was stable and CSD was narrow. In the SEM view, calcite and aragonite was obtained.

• Natural Product Sciences
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• v.8 no.3
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• pp.108-110
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• 2002

A new ardimerin (1) was isolated from the herb of Ardisia japonica. Its structure was determined by the elucidation of spectroscopic data and a chemical transformation. Compound (1) showed potent radical scavenging effect on DPPH radical $(IC_{50},\;0.32\;{\m}M)$.

• Journal of Microbiology and Biotechnology
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• v.10 no.1
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• pp.51-55
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• 2000

Surface culture fermentation using Aspergillus niger was studied for gluconic and citric acid production at different C/N ratios. A culture of A. niger was found to produce either gluconic acid alone, a mixture of gluconic and citric acid, or citric acid alone depending on the level of nitrogen in the medium (4 to 18mM). Glucose oxidase from the mycelial mat was also analyzed at different levels of nitrogen in the media. By choosing the level of nitrogen in the medium at the start of fermentation, it is possible to produce either of the two acids as the dominant product or the two together as a mixture.

• Proceedings of the Polymer Society of Korea Conference
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• 2006.10a
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• pp.165-165
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• 2006

We prepared nonlinear optical (NLO) polymers possessing thermal and temporal stability, which were based on the polyimides appended with NLO chromophores. NLO chromophores with a terminal hydroxyl group have been synthesized by coupling between aminobenzene or julolidine donor and phenylene bridge, and then subsequent coupling between the resulting product and tricyanofuran acceptor. The chromophores were chemically bonded to the polyimides backbone through Mitsunobu reaction. The NLO polymers showed $160-170^{\circ}C$ of Tgs and were thermally stable up to $200^{\circ}C$. We obtained optical quality films by spincoating and evaluated their electro-optical properties and temporal stability.

• Natural Product Sciences
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• v.4 no.2
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• pp.78-83
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• 1998

Chemical investigation on a sample of the needles of Himalayan Taxus baccata has resulted in the isolation of several taxoids including taxol (1) 10-deacetyl-baccatin III (2) and 2-deacetoxytaxinine J (3) along with different lignans (6 and 7) and simple phenolics (8, 9, 10, 11 and 12). The occurrence of 4-(4'-hydroxyphenyl)-butane-2-one and 4-(4'-hydroxyphenyl)-trans-but 3-ene-2-one (8) in Taxus species is reported for the first time. The $^{13}C-NMR$ spectral data of two rearranged taxiod constituents, brevifoliol (4) and 13-decinnamoyltaxchinin B (5) are presented. The acid-catalyzed decomposition of taxol has been discussed. The synthesis of other two constituents, rhododendrol (10) and hibalactone (7) has been described.

• Bulletin of the Korean Chemical Society
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• v.29 no.2
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• pp.328-334
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• 2008

The effects of catalyst preparation on the reaction route and the mechanism of biphenol (BP) hydrogenation, which consists of a long series-reaction, were studied. Pd/C catalysts were prepared by incipient wetness method and precipitation and deposition method. The reaction behaviors of the prepared catalysts and a commercial catalyst along with the final product distributions were very different. The choice of the catalyst preparation conditions during precipitation and deposition including the temperature, pH, precursor addition rate, and reducing agent also had significant effects. The reaction behaviors of the catalysts were interpreted in terms of catalyst particle size, metal distribution, and support acidities.