• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1994.05a
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• pp.90-93
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• 1994

A surface acoustic wave(SAW) sensor for the detection of odorants has been constructed by depositing various phospholipids and fatty acids onto the surface of the SAW device. Applying the Langmuir-Blodgett technique. it was possible to deposit the optimal number of layer which was found to be between 10 and 20. The characteristics of a SAW device operating at 310 MHz deposited with phosphatidyl choline were analysed. Menthone, amylacetate, acetion, and other organic gases sho7\\\\`ed different affinities to the coated lipids. An explanation is given for differant odorant affinities based on the monolayer properties of phospholipids. The identification of odorants depending on the type of lipid used for coating is discussed in terms of a comparison of their normalized resonant frequency chi It pat terns. Using a number of different lipid-coated SAW devices. odorants can be identified by a computerized pattern recognition algorithm.

• Environmental Engineering Research
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• v.24 no.2
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• pp.271-278
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• 2019

Mass cultivation of microalgae is necessary to achieve economically feasible production of microalgal biodiesel. However, the high cost of nutrients is a major limitation. In this study, corncob extract (CCE) was used as an inorganic and organic nutrient source for the mass cultivation of Chlorella vulgaris (C. vulgaris). Chemical composition analysis of CCE revealed that it contained sufficient nutrients for mixotrophic cultivation of C. vulgaris. The highest specific grow rate of C. vulgaris was obtained at pH of 7-8, temperature of $25-30^{\circ}C$, and CCE amount of 5 g/L. In the analysis using various growth models, Luong model was found to be the most suitable empirical formula for mass cultivation of C. vulgaris using CCE. Analysis of biomass and production of triacyglycerol showed that microalgae grown in CCE medium produced more than 17.23% and 3% more unsaturated fatty acids than cells cultured in Jaworski's Medium. These results suggest that growing microalgae in CCE-supplemented medium can increase lipid production. Therefore, CCE, agricultural byproduct, has potential use for mass cultivation of microalgae.

• Journal of Animal Environmental Science
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• v.11 no.1
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• pp.17-24
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• 2005

Aerobic sequencing batch reactor (SBR) was used to treat screened dairy wastewaters. The study examined the production of volatile organic compounds (VOCs) and volatile fatty acids (VFAs) in the aerobic SBR and raw manure effluent storage over 35 days. The reduction of total VFAs in the aerobic SBR was over $59\%$ removal than that of the raw manure. Acetic acid production in the aerobic SBR and the raw manure effluent storage were kept 138 and 286 mg/L. The propionic acid in the aerobic SBR was 1.9 mg/L, while the raw manure effluent storage was 68 mg/L, respectively. The concentrations of VOCs in the aerobic SBR reactor and effluent fill down remarkably than the raw manure storage. The results confirmed that the aerobic biological treatment is an essential requirement for minimizing odor problems.

• Korean Chemical Engineering Research
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• v.51 no.4
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• pp.482-486
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• 2013

Recently, biohydrocarbons are gathering an interest as a new bioenergy due to the versatile applicability. In the present work, a process is proposed for the recovery of lipids from Recombinant E. coli MG1655 which provides longer chain fatty acids. After the growth of the recombinant E. coli, the cells were disrupted by high pressure homogenizer for obtaining intracellular lipids and the resulting solutions were centrifuged and extracted. For the efficient cell disruption with high pressure homogenizer, the pressure higher than 5,000 psi was required. In addition, under the conditions of applied pressure 5,000 to 20,000 psi, 1~3 pass homogenizing was enough for the more than 90% cell disruption. As organic solvents for extraction of lipid, hexane/isopropyl alcohol and ethyl acetate/ethanol systems showed excellent extracting power. With these solvent systems, the 60% lipid could be recovered. Moreover it was found that the extracted lipids contained long-chain fatty acids such as $C_{12}$, $C_{14}$, $C_{16}$ and $C_{18}$.

• The Korean Journal of Community Living Science
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• v.28 no.4
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• pp.515-524
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• 2017

This research investigated the physicochemical properties and antioxidant activities of hot air-dried red mustard (Brassica juncea L.) leaf (HR) and freeze-dried red mustard leaf (FR). Crude protein content was highest in FR, and crude fat and carbohydrate contents were highest in HR. However, moisture and crude ash contents were not significantly different between the two drying methods. Total free sugars were higher in HR compared with FR. Sucrose, fructose, and glucose were the major free sugars in both HR and FR. Contents of essential and non-essential amino acids were higher in HR compared with FR. The major organic acid of FR was malic acid, and the major organic acid of HR was malic acid. The contents of saturated and unsaturated fatty acids were higher in HR than in FR. Total mineral contents were higher in FR (10,187.22 mg%) compared with HR (9,815.80 mg%). Major minerals were K, Ca, and Na in the two drying methods. The contents of vitamins C and E in HR were higher than those in FR. Total polyphenol contents showed no significant difference between the two methods. However, total flavonoid contents in HR were higher than in FR. The $IC_{50}$ values of FR and HR in ABTS assay were 0.89 mg/mL and 0.65 mg/mL, respectively. The results of all experiments suggest that HR and FR can be natural candidates as a rich source of antioxidants for further chemical investigation.

• Food Science and Preservation
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• v.13 no.1
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• pp.43-49
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• 2006

The chemical components of Korean paprika according to cultivars were investigated and analyzed to provide basic data for food materialization and processing. Nitrogen free extract contents of President, Special and Fiesta were 6.64, 6.22 and $6.01\%$ respectively. The contents of crude lipid and crude fiber in the Special, President and Fiesta were similar. Mineral components of paprika were rich in $K(83.41\-152.98\;mg\%),\;Mg(28.66\~39.46\;mg\%)\;and\;Mn(10.34\~18.96mg\%)$. Among the cultivars of paprika, K content had a slightly higher level in the President than those of Special and Fiesta. The major free Sugars of paprika were glucose $(1.36\~1.45\%)$ and fructose$(0.06\~1.53\%)$, respectively. The contents of total amino acids in paprika were $1,168.08\;mg\%$ in the Special, $1,112.97\;mg\%$ in the President and $874.79\;mg\%$ in the Fiesta. The major amino acids in the paprika were lysine, aspartic acid and glutamic acid Abundant organic acids of paprika were tartaric $(2.34\~4.32\;mg\%)$, succinic $(2.01\~2.42\;mg\%)$ and malic acids $(0.67\~1.72\;mg\%)$. Eight fatty acids in paprika were identified and the major fatty acids were stearic $(15.11\~34.68\%)$ and linoleic acids $(32.12\~60.36\%)$. The contents of ascorbic acid in paprika were $263.45\;mg\%$ in the Special, $284.24\;mg\%$ in the President and $206.34\;mg\%$ in the Fiesta. Total phenolics and carotenoid contents were higher in President cultivar than any other cultivars.

• Korean Journal of Soil Science and Fertilizer
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• v.43 no.2
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• pp.188-193
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• 2010

The aim of this study is to evaluate the effects of organic materials on soil organisms. Changes in the community structure, and population density of soil organisms (microbes, nematodes, and microarthropods) were studied in a Korean ginseng field. Phospholipid fatty acids analysis showed that the relative abundances of bacteria, fungi, and actinomycetes did not differ significantly. The aerobes/anaerobes ratio was the lowest in soils amended with leaf mold, indicating that the decomposition speed was slow. Further, the addition of leaf mold to the soil enhanced the saturated/monounsaturated fatty acid ratio and cyclopropyl fatty acid/precursor ratio, which indicated an increase in environmental stresses. Application of pig manure compost (PMC) had positive effects on the population density of nematodes, and negative effects on that of oribatid mites. The population densities of nematodes, and microarthropods remained relatively low in the plots that had been treated with leaf mold or pig manure compost. It is suggested that pre-planting soil management directed at enhancing the biological decomposition efficiency should be continued over a long period to increase the soil bioactivity in virgin soils.

• Korean Journal of Microbiology
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• v.32 no.4
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• pp.252-257
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• 1994

A new hydrogen sulfide-oxidation bacterium, Thiobacillus sp. was isolated from waste coal mine water around Hawsun in Chunnam province. The isolate was motile gram-negative rod shape, formed spore and grew up to be aerobically facultative chemolithotroph by using energy released from the oxidation of reduced inorganic sulfur compounds. It could assimilate various kinds of organic compounds and grew well upon thiosulfate-supplemented basal medium. To the lelvel of 32 mM in thiosulfate concentration, thiosulfate in itself was utilized as energy source for growth. However, from those of the higher concentration than 32 mM, thiosulfate functioned specifically as the substrate inhibitor rather than as the energy source. It was found that the optimum thiosulfate concentration for growth was 32 mM. The G+C content of the DNA was 65.0 mol%. The isolate had 16 : 1 + 17$_{cyc}$, 16 : 0 as their major non-hydroxylated cellular fatty acids, 3-OH 12 : 0 as a hydroxylated fatty acid and also contained unidentified $C_{18}$ branched fatty acid. The ubiquinone system in the respiratory chain was Q-9. Based on the physiological and biochemical characteristics, the isolate was assigned to a novel species of the genus Thiobacillus sp. iw.

• Journal of the Korean GEO-environmental Society
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• v.9 no.2
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• pp.23-29
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• 2008

It has been mentioned that CSTR (Completely Stirred Tank Reactor) and UASB (Upflow Anaerobic Sludge Blanket) processes, the existing anaerobic processes, have problems in the treatment of highly concentrated particulate organic wastewater (HCPOW). Therefore, this paper discusses the treatment possibility of distillery wastewater which is a typical HCPOW using ADEPT (anaerobic Digestion Elutriated Phased Treatment) process. In the comparison of CSTR and ADEPT, ADEPT produced much higher gas than that of CSTR removing more organic matters and suspended solids in ADEPT process, ADEPT had no effect on the decrease in pH by volatile fatty acids and showed steady pH in spite of relatively short HRT. In the results of removal rate according to recycle ratios between 6Qin and 2Qin in ADEPT, 6Qin showed high removal rate during the operation time. Therefore it appears that ADEPT had an applicability for the treatment of distillery wastewater. ADEPT could be a economical process, due to the short HRT, the energy recovery by the methane production, and the utilization for carbon source of produced organic acid from the ADEPT-acid reactor.

• Journal of Korean Society of Environmental Engineers
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• v.22 no.3
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• pp.587-595
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• 2000

The most problems of domestic sewage for BNR(Biological Nutrients Removal) process are deficiency of carbon source and low C/N ratio. Primary sludge fermentation is seemed to be one of the best solutions producing biodegradable organic substrates. Soluble organic materials from sludge fermentation are mainly SCFAs(Short-Chain Fatty Acids) with 2~5 carbon atoms. In this research, it was attempted to apply $A_2/O$ process with the side-stream acid fermenter to improve the nutrients removal efficiency. The result showed that proper SCFAs production is about 3.000mg/L with SRT of 4~5 days. SCFAs yield of approximately 0.10~0.16 mg SCFAs(as COD) per mg of primary sludge(as COD) were achieved. The ratio of acetic. propionic. butyric and valerie acid were 1, 0.7, 0.5 and 0.6. Significant improvements of nutrients removal over 70% in BNR process were observed. thus will reduce the demand for chemical dosing to increase nutrients removal efficiency. When the fermentate was entered $A_2/O$ process, the ratio of phosphate release to substrate uptake amounts to $0.34gPO_4-Pg^{-1}COD$.