• Korean Journal of Microbiology
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• v.53 no.2
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• pp.103-117
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• 2017

The aim of this study was to evaluate the effect of green tea extract on probiotic potential, physico-chemical and functional properties of yogurt fermented with Lactobacillus acidophilus D11 or Lactobacillus fermentum D37 strains isolated from Doenjang. Probiotic activities such as the resistance to artificial digestive juices and the ability to adhere to epithelial cells were slightly higher in yogurt supplemented with green tea extract than in plain yogurt, which may be attributed to the increase in the number of lactic acid bacteria (LAB) by green tea extract supplementation. Furthermore, the microbiological and physico-chemical properties such as the number of LAB, organic acid production and viscosity were significantly (P<0.05) increased in yogurt added green tea extract compared to plain yogurt fermented with L. acidophilus D11. However, the green tea extract did not significantly (P>0.05) affect these properties of yogurt fermented with L. fermentum D37 strain. Meanwhile, the antibacterial activities against Escherichia coli O157 ATCC 43889, Salmonella enteritidis ATCC 13076, and Salmonella typhimurium KCTC 2514 and antioxidant activities including total phenol content, radical scavenging ability, and ferric-reducing antioxidant power were significantly higher in plain yogurt fermented with L. fermentum D37 than with L. acidophilus D11. The antibacterial and antioxidant activities of the yogurt were significantly (P<0.05) increased in proportion to the concentration of green tea extract added to plain yogurt. Consequently, green tea yogurt fermented with L. acidophilus D11 or L. fermentum D37 was considered to be a useful functional food that can inhibit the growth of pathogenic bacteria and scavenge the free radicals from the body cells.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.36 no.4
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• pp.50-57
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• 2018

Based on research projects and maintenance plans that have been carried out to observe changes in the appearance of buildings in Yangdong Village, Gyeongju, this study analyzed the process of changes in roof materials since the 1970s and drew the following conclusions. First, as the proportion of houses used in the yanggi and yanggi in the 1970s appears similar to that of Wagawa, it is believed that the village landscape has changed due to the use of modern materials by modernization and urbanization. Second, the initial stage of readjustment was designated as a folk data protection zone in 1977 and important folk data designation in 1984. However, due to the lack of a budget for repair and indiscriminate repair, the effectiveness of the project did not seem to have been high. As a result, the trend of decreasing the initial price of the previous period and increasing the use of materials such as yanggi and slate were continuing. Third, in the 1990s, the Cultural Heritage Administration pushed for restoration to the traditional method through extensive renovation projects, making efforts to restore traditional materials, such as reduction of the yanggi and roof, removal of the Hamseok roof, and an increase in the price of grass. Fourth, in the 2000s and thereafter, various readjustment projects were completed in the previous period, with the ratio of Wagwa and Choga greatly increased and the number of houses on the roof of slate reduced by about half, and the level of maintenance of the village's retirement homes was readjusted after the World Heritage List in 2010.

• The Journal of Korean Philosophical History
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• no.36
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• pp.173-202
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• 2013

In Korea The understanding about physical body contains several cultural and historical experiences. In the modern times several discussions bring about changes from moral training to physical education. Physical education shows clearly modern physical human being by destructions of confusional human being. In confusional philosophy human body contains moral facts such as moral training. Moral training shows right mind, so every physical acts target mental and cultural training. So in this capitalism, it is needed o training right moral training and right physical education.

• Clean Technology
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• v.27 no.1
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• pp.61-68
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• 2021

Selective catalytic reduction (SCR) is widely used as a method of removing nitrogen oxide in large-capacity thermal power generation systems. Uniform mixing of the injected ammonia and the inlet flue gas is very important to the performance of the denitrification reduction process in the catalyst bed. In the present study, a computational analysis technique was applied to the ammonia injection system design process of a denitrification facility. The applied model is the denitrification facility of an 800 MW class coal-fired power plant currently in operation. The flow field to be solved ranges from the inlet of the ammonia injection system to the end of the catalyst bed. The flow was analyzed in the two-dimensional domain assuming incompressible. The steady-state turbulent flow was solved with the commercial software named ANSYS-Fluent. The nozzle arrangement gap and injection flow rate in the ammonia injection system were chosen as the design parameters. A total of four (4) cases were simulated and compared. The root mean square of the NH3/NO molar ratio at the inlet of the catalyst layer was chosen as the optimization parameter and the design of the experiment was used as the base of the optimization algorithm. The case where the nozzle pitch and flow rate were adjusted at the same time was the best in terms of flow uniformity.

• Applied Chemistry for Engineering
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• v.34 no.4
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• pp.357-364
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• 2023

Selective catalytic reduction (SCR) is the most effective method for reducing nitrogen oxide emissions, but the operating temperature range of V₂O₅-WO₃/TiO₂ catalysts is narrow (300~400℃). In this study, a new catalyst with an operating temperature range of 200~450℃ was developed. The catalyst poison, ammonium bisulfate, generated during the SCR process can be removed by heating above 350℃. To increase the number of active sites and promote the dispersion of active materials, titanium isopropoxide (TTIP) treatment was performed on the TiO₂ support with various TTIP/TiO₂ mass ratios. Among them, the 5 wt% TTIP loaded catalyst showed improved performance due to higher thermal stability caused by high W dispersion and the formation of V⁵⁺. In addition, the 5 wt% TTIP-loaded catalyst prepared by a one-step co-precipitation method showed greater V-OH and W-OH dispersion and enhanced interactions in contrast to conventional methods, resulting in higher catalytic activity at lower temperatures. This review article aims to provide an accessible explanation for researchers investigating how to improve the surface properties of TiO2 catalysts using TTIP.

• Journal of Life Science
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• v.30 no.9
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• pp.743-748
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• 2020

Sulfate is a reductant that competes for electrons and may lower CH₄ production in the rumen. This study was designed to evaluate the beneficial effect of detoxified sulfur powder supplementation on in vitro rumen fermentation and methane mitigation. A ruminally cannulated Holstein Friesian cow was used as a rumen fluid source, and commercial pelleted concentrate was used as a substrate at 1 g dry matter. Treatments included the addition of detoxified sulfur powder at the rate of 0% (Control), 0.2% (T1), 0.4% (T2), 0.6% (T3), 0.8% (T4), and 1.0% (T5) as dry matter (DM) basis. The pH, total gas (TG), methane (CH₄) production, DM digestibility, organic matter (OM) digestibility, and volatile fatty acids (VFA) production were analyzed after 12 hr of incubation. The results showed that CH₄ production was significantly lowest in T1 (13.78 ml) but highest in the control (20.16 ml). Insignificantly higher total VFA was observed in control and T1 (64.99 and 64.28 mM, respectively) compared to other treatments after 12 hr of incubation. After 12 hr of incubation, the significantly lowest acetate:propionate was observed in T1 (1.90) while the highest was observed in T4 (2.44). However, no significant differences were recorded for pH, TG, DM digestibility, OM digestibility, acetate, propionate, and butyrate between the control and T1. Total number of bacterial DNA copies was significantly lower in the treatment group than the control. Therefore, it can be concluded from this study that detoxified sulfur at 0.2% inclusion level is optimal for production performance and ruminal CH₄ mitigation.

• Journal of the Korean Society of Food Science and Nutrition
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• v.39 no.10
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• pp.1528-1534
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• 2010

The antibacterial effects of seed decontamination during presoaking before sprouting as an intervention step for eliminating foodborne pathogens on red radish seeds were evaluated. The effect of seed decontamination on seed germination rate was also evaluated. Red radish seeds were inoculated (at a level of 3 to 4 log CFU/g) with Listeria monocytogenes ATCC 19111 and decontaminated with 20,000 ppm calcium hypochlorite, 50 and 100 ppm chlorinated water, acidic electrolyzed water, low-alkaline electrolyzed water, and ozonated water for 6 hours. The control seeds were immersed in distilled water. The germination rate was measured on each treatment for 48 hours. Treatments with 20,000 ppm calcium hypochlorite, acidic and low-alkaline electrolyzed water were more effective than treatments with chlorinated water and ozonated water. Immersion in 20,000 ppm calcium hypochlorite resulted in the largest microbial reduction (more than 3 logs). Treatments with acidic and low-alkaline electrolyzed water reduced APC by 3 logs and L. monocytogenes counts by 2 logs. After sprouting, APC and L. monocytogenes counts on seeds treated with 20,000 ppm calcium hypochlorite, acidic and low-alkaline electrolyzed water were significantly lower than the control. The germination rate ranged from 93.5% to 97.7% except for 20,000 ppm calcium hypochlorite (from 82.3% to 84.8%) after 48 hours. Although the treatments tested in this study will not eliminate L. monocytogenes on inoculated red radish seeds, the results show that rapid growth of surviving cells during sprouting could be prevented if red radish seeds are given a presoak treatment used in combination with a disinfectant treatment of irrigation water.

• Applied Chemistry for Engineering
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• v.10 no.4
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• pp.557-562
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• 1999

The reaction properties of Pd. Pd-Ce and Pd-La catalysts supported on ${\gamma}-Al_2O_3$ were investigated in the oxidation reaction of methane($CH_4$) exhausted from the compressed natural gas vehicle in a U-tube flow reactor with gas hourly space velocity of $72,000h^{-1}$. The catalysts were characterized by X-ray diffraction(XRD), X-ray photoelectron spectroscopy(XPS), BET surface area and hydrogen chemisorption. Pd catalyst prepared by $Pd(NO_3)_2$ as a palladium precursor and calcined at $600^{\circ}C$ showed the highest activity for a methane oxidation. Catalytic activity of calcined $Pd/{\gamma}-Al_2O_3$ in which most of palladium was converted into palladium oxide species was higher than that of reduced $Pd/{\gamma}-Al_2O_3$ in which most of palladium existed in palladium metal by XRD. As increasing the number of reaction cycles in the wide range of redox, the catalytic activity of $Pd/{\gamma}-Al_2O_3$ was decreased and the highly active window became narrower. Lanthanum oxide promoted Pd catalyst, $Pd/La/{\gamma}-Al_2O_3$ showed enhanced thermal stability compared with $Pd/{\gamma}-Al_2O_3$ even after aging at $1000^{\circ}C$, which was ascribed to the role of La as a promoter to suppress the sintering of palladium metal and ${\gamma}-Al_2O_3$ support. Almost all of methane was removed by the reaction with NO at the redox ratio of 1.2 in case of oxygen excluded steam, but that activity was significantly decreased in the steam containing oxygen.

• Journal of the Korean Chemical Society
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• v.44 no.3
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• pp.212-219
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• 2000

An absorption spectrometry coupled with flow injection analysis has been developed and tested for the analysis of the Cr$_2O_7^{2-}$/Nn$O_4^-$ mixtures. Even though one has to inject the sample twice into the FIA system and the process of the sample treatment is required to completely destroy the Mn$O_4^-$ ion for the analysis of the Cr$_2O_7^{2-}$ ion, the new method has definite advantages over the current method. It utilizes only a single analytical wavelength (570 nm) and enables one to construct calibration curves which accurately follow the Beer's law over wide ranges of analytical concentrations of both ions ($2.0{\times}10^{-6}$M∼$8.0{\times}10^{-3}$M for Cr$_2O_7^{2-}$ ion, $2.0{\times}10^{-6}$M∼$4.0{\times}10^{-3}$M for MnO4- ion).

• The Korean Journal of Food And Nutrition
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• v.18 no.1
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• pp.63-71
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• 2005

Panax ginseng leaves are produced as the by-product when Panax ginseng roots were harvested. The Panax ginseng leaves was examed for the applicable possibility as the functional food. In this study, the changes in chemical composition of Panax ginseng leaves was examed by three methods as the hot-air dried(DRT), the aged tea(AGT) and the heat processed tea(HPT). The general composition of Panax ginseng leaves tea was shown as similar results in 3 different process methods. The level of the crude lipid and reducing sugar concentration were decreased slightly in HPT. The free sugar content of DRT was higher than the HPT and AGT. The existence of the higher content of free sugar composition in order are sucrose, fructose and glucose. The concentration of serine was the highest in the free amino acids, which were shown from 309.6 mg% to 336.6 mg%. The contents of free amino acid in Panax ginseng leaves made by DRT was higher than by AGT and HPT. The concentration of Ca was shown as the highest content among the minerals and was 2,115 mg%. The contents of minerals were existed in order of Ca, K, Mg, P, Na, Mn, Fe, Zn and Cu. But there were hardly any remarkable differences of mineral concentrations of Panax ginseng leaves tea made by different processing methods. The concentration of water soluble solid of Panax ginseng leaves tea processed by HPT was higher than by DRT and AGT. The concentration of ascorbic acid was shown the highest value of 424.4mg% in HPT. There was no differences in the fatty acid composition according to their processing methods. The concentration of palmitic acid was higher than that of other fatty acid. The order of fatty acid concentration were palmitic aicd, linoleic acid, linolenic acid, oleic acid and stearic acid, abundantly. As a conclusion, HPT was shown as the best process method for the production of Panax ginseng leaves tea.