• Journal of the Korea Organic Resources Recycling Association
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• v.10 no.1
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• pp.96-101
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• 2002

This research was conducted to find the optimal condition in codigestion of food waste and sewage sludge with various mixing ratios. The analysis of degradation characteristics were based on the variations of methane production as well as methane production rate (MPR). BMP values were getting higher as the addition of foodwaste increased. But the lag-phase were prolonged when the foodwaste was over 40%, Nonlinear regression was conducted with the cumulative methane production data. Not only thermophilic but mesophilic condition, 40% of foodwaste addition showed maximum MPR. Higher mixing ratio which is over 50% were unprofitable in gaining higher MPR values. The most important factor in thermophilic co-digestion was substrate concentration. But in mesophilic co-digestion, both substrate concentration the mixing ratio had major effects on MPR. The most probable reasons of the synergetic effects in co-digestion of foodwaste and sewage sludge were the balanced nutrient expressed as C/N ratio and increased kinetic constants of hydrolysis by the mixed co-substrates.

• Journal of Mushroom
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• v.15 no.1
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• pp.31-37
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• 2017

In this study, we investigated the amino acids content of shiitake mushrooms grown in eight different media and under three different temperature conditions. The sawdust media were supplemented with 4 kinds of nutrients - rice bran, barley, bean curd refuse, and red ginseng refuse in an 8:2 ratio with or without 0.5% calcium chloride, and the fruiting temperature was set to low ($13-15^{\circ}C$), medium ($18-20^{\circ}C$), or high temperatures ($24-26^{\circ}C$). Seventeen amino acids were detected, and the content varied depending on the compositions of the media. The highest total amino acid content (209.7 mg/g) was measured in mushrooms from the media with red ginseng refuse, and the glutamic acid content was the highest (51.3 mg/g) in mushrooms from the media with barley. In terms of fruiting temperature, the amino acid content was the highest (38.2%) at medium temperature followed by the content at low (32.5%) and high temperature (29.3%). The amino acid composition of shiitake mushrooms was similar between the medium and low temperature conditions.

• Applied Chemistry for Engineering
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• v.27 no.5
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• pp.532-536
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• 2016

In this study, single-stage continuous anaerobic reactors to treat sewage sludge were operated under different temperature (55 and $35^{\circ}C$; $R_{TAD}$ and $R_{MAD}$) to evaluate the reactor stability and performance of the thermophilic and mesophilic anaerobic digestion. During the overall digestion, both anaerobic reactors maintained quite stable and constant pH and total alkalinity (TA) values in the range of 6.5-8.0 and 3-4 g $CaCO_3/L$, respectively. After the start-up period, $R_{TAD}$ showed 10% higher VS removal efficiency than that of $R_{MAD}$ ($R_{TAD}$; 43.3%; $R_{MAD}$ : 33.6%). Although organic acids such as acetic and propionic acid were detected in both anaerobic reactors at the start-up period, all organic acids in $R_{TAD}$ and $R_{MAD}$ were consumed at the steady state condition. Also $R_{TAD}$ showed 31.4 % higher methane production rate (MPR) than that of $R_{MAD}$ at the steady state condition ($R_{TAD}$; 243 mL $CH_4/L/d$; $R_{MAD}$ : 185 mL $CH_4/L/d$). Meanwhile, the experimental results indicated similar methane yield between $R_{TAD}$ and $R_{MAD}$.

• Journal of Environmental Health Sciences
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• v.27 no.1
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• pp.119-123
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• 2001

철 농도변화에 따른 대사산물 생성에 대한 반응은 중온조건에서 회분식 실험으로 수해하였다. 철의 농도가 40mg/$\ell$까지는 철 농도의 증가에 따라 수소생성율도 증가하였다. acetate 생성율은 철의 농도가 증가함에 따라 감소하였다. Butyrate, ethanol 및 butanol은 각각 철 농도가 200,200 및 400mg/$\ell$에서 최대 생성율을 나타내었다. 철의 농도가 200mg/$\ell$이상의 농도엘 때에 propionate, i-butyrate 및 valerate 생성율이 철의 농도가 200mg/$\ell$ 이하의 경우 보다 낮았다. 미생물농도의 경우 철 농도가 300mg/$\ell$까지는 농도가 증가함에 따라 미생물농도도 증가하였다.

• Proceedings of the Korea Society for Energy Engineering kosee Conference
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• 2007.11a
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• pp.246-249
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• 2007

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2003.11a
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• pp.443-444
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• 2003

The developments on desulfurization have been focused on the application to the advanced power generation systems such as integrated gasification-combined cycle (lGCC) and the gasification-molten carbonate fuel ceil (MCFC). The gas produced from the coal gasification contains H$_2$S and other hazardous sulfur compounds, which must be removed to avoid corrosion and environmental problems. (omitted)

• Proceedings of the SAREK Conference
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• 2004.06a
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• pp.159-159
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• 2004

• the MEAT Journal
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• s.35 winter
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• pp.34-45
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• 2008

People can be exposed to various microorganisms when they eat yukae (seasoned raw meat) because yukae is eaten raw. The purpose of this study was to find out microbial distribution in yukae. In this experiment, 5 restaurants serving yukae were chosen in Daegu area. Mesophilic microorganisms and coliforms were measured by Korean Food Standards Codex. Analyses of Salmonella spp., Listeria monocytogenes, Staphylococcus aureus and Escherichia coli O157:H7 were conducted. As results, mesophilic microorganisms ranged 6.6$\times$103-2.7$\times$105 CFU/g and coliforms ranged 8.9$\times$101-2.1$\times$105 CFU/g. Salmonella spp., Listeria monocytogenes and Escherichia coli O157:H7 were not detected in all 5 samples. However, Staphylococcus aureus was detected in 1 sample out of 5 samples. Hygiene practice during production, processing and cooking process is required.

• Journal of Astronomy and Space Sciences
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• v.21 no.4
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• pp.343-350
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• 2004

The charge exchange (or transfer) due to collision with hydrogen has important effects on the physical characteristics of astrophysical plasma. In this paper, collisional ionization equilibrium in the temperature range of ${\sim}1,000--80,000K$ are investigated for C, N, and O ions including the effects of charge exchange. The calculated ionic abundance fractions are compared with those of previous works. The ionic abundance fractions calculated in the paper can be used in understanding the spectroscopic properties of warm interstellar medium. It is also found that the ratio between the degree of ionization of oxygen and that of hydrogen shows big difference with the previously well-known result for the environment where the collisional ionization is not important. This implies that investigations on the collisional ionization in the warm interstellar medium are required.

• Food Science of Animal Resources
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• v.27 no.2
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• pp.197-202
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• 2007

People can be exposed to various microorganisms when they eat yukae(seasoned raw meat) because yukae is eaten raw. The purpose of this study was to find out microbial distribution in yukae. In this experiment, 5 restaurants serving yukae were chosen in Daegu area. Mesophilic microorganisms and coliforms were measured by Korean Food Standards Codex. Analyses of Salmonella spp., Listeria monocytogenes, Staphylococcus aureus and Escherichia coli O157:H7 were conducted. As results, mesophilic microorganisms ranged $6.6{\times}10^3-2.7{\times}10^5\;CFU/g$ and coliforms ranged $8.9{\times}10^1-2.1{\times}10^5CFU/g$. Salmonella spp., Listeria monocytogenes and Escherichia coli O157:H7 were not detected in all 5 samples. However, Staphylococcus aureus was detected in 1 sample out of 5 samples. Hygiene practice during production, processing and cooking process is required.