• Korean Journal of Pharmacognosy
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• v.44 no.4
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• pp.313-319
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• 2013

A Korean folk medicine, "DangYak (當藥)" has been used as a bitter stomachic in Korea. With regard to the botanical origin of this crude drug, it has been considered to be from Swertia species (Gentianaceae), but there was no pharmacognostical confirmation on it. In this study, the morphological and anatomical characteristics of three Swertia species growing in Korea, Swertia japonica Makino, S. pseudochinensis Hara and S. tetrapetala Pall. were compared to clarify the botanical origin of "DangYak". As a result, it was determined that the commercial "DangYak" from Korean traditional market was proved to be the whole plant body mixture of Swertia japonica and Swertia pseudochinensis.

• Corrosion Science and Technology
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• v.15 no.3
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• pp.135-140
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• 2016

Piping and equipment are degraded by flow-accelerated corrosion (FAC) in nuclear power plants. FAC causes numerous problems and nuclear utilities maintain programs to control FAC. The key parameters influencing FAC are hydrodynamic conditions, water chemistry, and effect of materials. Recently, a nuclear utility has planned slight power uprates in Korea. Operating conditions need to be changed in the secondary system according to power uprates. This study analyzed the effect of wall-thinning caused by power uprates. The change of operation data in the secondary cycle is reviewed, and wall-thinning rates are analyzed in the main lines. As a result, two phase (mixture of water and steam) lines have a greater impact than a water line under power uprate conditions. Also, the quality of steam is the most important factor for FAC in two phase lines.

• Journal of Environmental Science International
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• v.13 no.2
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• pp.143-148
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• 2004

In this paper, the properties of inter - locking block using fly ash are discussed in order to provide economical advantages and improve quality, and protect environment and recycle resources. Fly ash is the by-product of coal in thermal power plant. The experimental parameters are fly ash content, the amount of AE water - reducing agent and mixing proportion of cement mortar. According to the experimental results, the improvement of quality in the side of strength, absorption ratio and freeze - thaw resistance for manufacturing inter -locking block and the curtailment of cost can be achieved in case of 15% of fly ash and 0.3% of AE water- reducing agent are mixed into mortar mixture of 1 :6(C:S).

• Analytical Science and Technology
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• v.28 no.2
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• pp.112-116
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• 2015

Extraction of quaternary ammonium compounds (choline and betaine) from plant samples (spinach) using ion exchange resin (AG1, OH⁻ form) is a very simple and inexpensive approach. However, it is very hard to determine amounts of choline and betaine simultaneously using high-performance liquid chromatography-ultraviolet (HPLC-UV) detection. Unlike choline, betaine has low molar absorptivity in UV-visible (UV-Vis) region, which makes it difficult to carry out UV-Vis detection of betaine. The mixture of quaternary ammonium compounds (choline and betaine) was derivatized using 2-bromo acetophenone as a derivatizing agent. As a result, choline did not react with the derivatizing agent, whereas betaine formed a betaine derivative. This betaine derivative exhibited detectable UV absorption with baseline separation between choline and the betaine derivative. Thus, with this method, choline and betaine can be determined simultaneously by using the HPLCUV method through one-step derivatization, which is an easy, sensitive, and reliable method.

• Proceedings of the KIEE Conference
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• 2011.07a
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• pp.1374-1375
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• 2011

Mixed combustion expert system is implemented to prevent various problems in combustion process by increasing rate of mixing low calorific value coal to reduce costs. This system shows optimal coal mixture rate by interfacing CBS(Coal Blending Screener, Implementing slagging and fouling factors by coal characteristic and algorithm), SGE(Stream Generate Expert, Combustion process model) and CFS(Configured Fireside Simulator, Computational fluid dynamics).

• Proceedings of the Korea Concrete Institute Conference
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• 1995.04a
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• pp.189-194
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• 1995

This paper presents the material properties and production of 500 and 700 kg/$\textrm{cm}^2$ high strength concrete for the practical utilization. A series of Lab. tests were conducted to optimize the material mixture of high strength concrete and then mock-up tests were performed through the Remicon Batch Plant. This paper stresses the material conditions for the final stage of production of 500 and 700 kg/$\textrm{cm}^2$ high strength concrete, just prior to the practical use on 28-story Samsung Shin-Daebang Housing-Commercial Combined Building with 8-story basements.

• Korean Journal of Pharmacognosy
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• v.31 no.1
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• pp.16-22
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• 2000

These studies were designed to determine the potential cytotoxic activity of MeOH extracts of 65 crude drugs against leukemia L1210 and $P388D_1$, cell line in vitro, of which 25 samples were selected. The n-BuOH extracts of 25 samples were measured using the same method and nine were selected. These samples were measured for the potential antitumor activity against $P388D_1$, for life span in vivo, and against sarcoma 180 for tumor weight. On the basis of results, Notoginseng Radix, Anemarrhenae Rhizoma, Albizziae Cortex, Portulacae Herba, Bupleuri Radix were evaluated the effective plant on the antitumor activity. In addition, the mixture of Notoginseng Radix and Albizziae Cortex was evaluated to enhance the antitumor activity in vivo.

• 한국신재생에너지학회:학술대회논문집
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• 2007.06a
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• pp.784-787
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• 2007

A process flowsheet simulation model based on ASPEN PLUS was developed to investigate the effect of co-gasification of coal and rice husk on the gasifier performance and pollutant emissions in IGCC power plant. The analyses were done for an 02-blown, pulverized gasifier using coal and rice husk as feedstock, parameter employed the blending ratio of rice husk in coal were investigated. From the simulation results, it was found that gaseous pollutant emissions were reduced substantially with the increase of the blending ratio of rice husk. An optimum range between 15% and 25% rice husk-to-coal ratio was found to be the optimum point in terms of gaseous pollutant emission per energy output for sui fur and nitrogen compounds.

• The Journal of Natural Sciences
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• v.18 no.1
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• pp.91-97
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• 2007

The Korean name "Bizooki" tree was named by the shape of winter bud which is like a slim bow. There are four scientific names in the tree which are Cleyera japonica Thunberg, Cleyera ochnacea DC, Sakakia ochnacea Nakai, and Ternstroemia gymnanthera. And the English name are Japanese Ternstroemia and Japanese Cleyera. "Bizooki" tree has planted at Buddhist temples in Japan for the ritual. The best result of stem cutting in "Bizooki" tree, 100 percent of rooting, could be accomplished in July when cuttings were done on the mixture-soil containing the same rates by volume of vermiculite, peatmoss and perlite with cuts processed with IBA 1,000 mg/l under the circumstances that 70% of shade, plastic mulching, and mist were conditioned.

• Elastomers and Composites
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• v.31 no.5
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• pp.327-334
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• 1996

A correlative analysis has been carried out to predict the average particle size of rubber dispersed phase In high impact polystyrene manufactured by bulk polymerization. To do the correlation, a mechanistic model suggested previously by the author was used for describing the size of stabilizing particles agitated under the turbulent viscous shear subranges in a prepolymerization reactor, where the rubber particles were assumed to be formed at the time of phase inversion in the reactor. Viscosities required for the model were postulated to describe the overall behavior of butadiene rubber and polystyrene mixture along the wide range of conversion. The good agreement between the model and the experimental data from a plant was quite satisfactory for the prediction of the average rubber particle size of high impact polystyrene.