• Korean Chemical Engineering Research
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• v.46 no.3
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• pp.535-539
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• 2008

Conversion to oil, yield of styrene and formation of side products such as ${\alpha}-methyl$ styrene, ethyl benzene, benzene, toluene, dimer and trimer were affected by residue formed during thermal degradation. Also, control of reaction temperature had a difficulty at the first stage. Thus, new reaction system using wetted-wall type reactor was proposed and examined on various parameters such as reaction temperature, feeding rate and removal velocity of formed vapor. Optimun condition was obtained from continuous thermal degradation using wetted-wall type reactor and reaction kinetic study was carried out at new type reactor.

• Journal of Korean Society on Water Environment
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• v.21 no.4
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• pp.403-409
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• 2005

Methyl tert-butyl ether (MTBE) contamination in groundwater often coexists with benzene, toluene, ethylbenzene, and xylene (BTEX) near the source of the plume. Then, groundwater contamination problems have been developed in areas where the chemical is used. Common sources of water contamination by BTEX and MTBE include leaking underground gasoline storage tanks and leaks and spills from above ground fuel storage tanks, etc. In oil-contaminated environments, anaerobic biodegradation of BTEX and MTBE depended on the concentration and distribution of terminal electron acceptor. In this study, effect of electron acceptor on the anaerobic biodegradation for BTEX and MTBE-contaminated soil was investigated. This study showed the anaerobic biodegradation of BTEX and MTBE in two different soils by using nitrate reduction, ferric iron reduction and sulfate reduction. The soil samples from the two fields were enriched for 65 days by providing BTEX and MTBE as a sole carbon source and nitrate, sulfate or iron as a terminal electron acceptor. This study clearly shows that degradation rate of BTEX and MTBE with electron acceptors is higher than that without electron acceptors. Degradation rate of Ethylbenzene and Xylene is higher than that of Benxene, Toluene, and MTBE. In case of Benzene, Ethylbenzene, and MTBE, nitrate has more activation. In case of Toluene and Xylene, sulfate has more activation.

• Journal of the Korean GEO-environmental Society
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• v.11 no.8
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• pp.65-71
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• 2010

In this study, we have evaluated biodegradability of diesel-oxygenates including DBM and gasoline-oxygenates having similar physio-chemical properties using indigenous aerobic microorganisms from a diesel-contaminated soil. Toluene and Ethanol have shown higher biological activity and the first-order degradation rate constants ranged around $0.11{\sim}0.3day^{-1}$. However, MTBE, gasoline-oxygenate has shown as a limited substrate. Moreover, As increased initial concentrations of DBM and TGME, degradation rates of those were decreased relatively. As a strategy to evaluate biodegradability of DBM and TGME, reduction of diesel-oxygenates, $CO_2$ production and toxicity by algae were monitored. This results indicated possible mineralization of diesel-oxygenates, But we could predict that residual byproduct produced even though complete consumption of diesel-oxygenates were observed if algal toxicity variation considered. In conclusion, it is the first report that diesel-oxygenates including DBM could be biodegraded effectively by indigenous soil microorganisms and this result increased the possibility of bioremediation technology to apply into oil-contaminated sites.

• Polymer(Korea)
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• v.28 no.2
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• pp.103-110
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• 2004

The biodegradable poly($\varepsilon$-caprolactone) (PCL) microcapsules containing tocopherol were prepared by oil-in-water emulsion solvent evaporation method. The features of the microcapsules were investigated in the manufacturing conditions and degradation behaviors. The form and structural feature of the microcapsules were measured by scanning electron microscope and X-ray diffraction, respectively. The surface free energy of the microcapsules was executed using contact angle measurement. As a result, the microcapsules were more stable and spherical with poly(vinyl alcohol) given in a surfactant. The surface free energy and crystallinity of microcapsules were decreased with increasing the core concentration, and degradation of PCL was occurred after 21 days. The release behaviors were examined by Uv/vis. spectrophotometer. It was found that the release rate of the microcapsules was increased with increasing the stirring rate, due to the increased interface between microcapsules and release media.

• Korean Chemical Engineering Research
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• v.45 no.4
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• pp.396-399
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• 2007

Organic residue and carbonized solid producing from the thermal degradation gave a influence on oil conversion, formation of styrene and side products such as ${\alpha}-methyl$ styrene, ethyl benzene, dimer. Thus, new reaction system using wetted-wall type reactor was proposed and examined on influence of various parameters such as reaction temperature, feeding rate and removal velocity of formed vapor. Optimum condition were obtained from continuous thermal degradation using wetted-wall type reactor and styrene was continuously obtained as the yield up 65%.

• Korean Journal of Food Science and Technology
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• v.36 no.2
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• pp.299-305
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• 2004

Genetically Modified (GM) corn 'Bt11' was developed to promote insect resistance using crylA (b) gene derived from Bacillus thuringiensis. Effects of heat, pressure, and ${\alpha}-amylase$ on DNA fragment degradation in Btll corn were examined through PCR. Whereas DNA fragment degraded completely within 4 min at $150^{\circ}C$ and by autoclave, most remained after oil-frying, boiling, and drying-autoclave. Treatment of ${\alpha}-amylase$ enzyme did not affect DNA fragment degradation. Among 65 corn-processed foods analyzed, 9 were detected as GM corn-containing foods(13.6%).

• Journal of the Institute of Electronics and Information Engineers
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• v.49 no.9
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• pp.353-361
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• 2012

In this paper, we propose a improvement method of vision inspector for T type welding nut using an auto sorting system. We used edge and thread detection with histogram of image which is captured by machine vision camera. We also used a binary morphology operation for a detection of spot. A major problem in this vision inspector is abnormal operation caused by degradation of image acquired. These degradations caused by oil pollution on conveyer belt. For overcome this problem, we introduce a pre-processing using a masked histogram equalization on the image acquired. Histogram equalization is applied on masked region (nut part) for increase contrast. As a result, we can remove features caused by oil pollution on background and reduce a ratio of abnormal operation from 10.0 % to 0.2 %.

• 한국생물공학회:학술대회논문집
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• 2003.04a
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• pp.600-604
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• 2003

This study pointed at isolation of bunker-C oil degrading bacteria and then estimation of it's degrading capability in environmental conditions. Degradation ratio of the excellent isolate was appeared to 40.5% and 44.7% when the oil was treated to 1% and 5%, respectively. The isolate was identified to Acinetobater calcoaceticus SEBCM. In pH test, high degrading effect was appeared to about 73% at pH 6 and pH 7, and low degrading ratio was 37% at pH 4. Its growth condition at temperature has not large variation in $15^{\circ}C\;{\sim}30^{\circ}C$, Quantity of nitrogen for it's good growth was ranged of $0.5\;g/L{\sim}2\;g/L$. As these results, we realized that this isolate have good activity when treated to $15\;{\sim}30^{\circ}C$ of temperature and $6{\sim}7$ of pH.

• Food Science of Animal Resources
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• v.34 no.1
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• pp.1-6
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• 2014

Pidan and salted duck eggs are of nutritional rich alternative duck egg products which are predominantly consumed in China, Thailand, South Korea and other Chinese migrated countries. Both eggs are rich in proteins, lipids, unsaturated fatty acids and minerals. A Pidan whole egg contains 13.1% of protein, 10.7% of fat, 2.25% of carbohydrate and 2.3% of ash, whereas the salted duck egg contains 14% of protein, 16.6% of fat, 4.1% of carbohydrate and 7.5% of ash. The fresh duck egg contains a range of 9.30-11.80% of protein, 11.40-13.52% of fat, 1.50-1.74% of sugar and 1.10-1.17% of ash. Proteins, lipids, and ash contents are found to be greatly enhanced during the pickling and salting process of pidan and salted duck eggs. However, the alkaline induced aggregation of pidan leads to degradation and subsequent generation of free peptides and amino acids. Very few amino acids are found to be lost during the pickling and storage. However, no such losses of amino acids are reported in salted duck eggs during the salting process of 14 d. Phospholipids and cholesterol contents are lower in pidan oil and salted duck egg yolk oil. Thus, the pidan and salted duck eggs are nutritionally rich alternatives of duck egg products which will benefit the human health during consumption.

• Polymer(Korea)
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• v.30 no.3
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• pp.202-206
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• 2006

The plasticized cellulose diacetate (CDA) was prepared by melt processing methods using triacetine (TA) as a plasticizer. Additionally, processability of CDA was enhanced by using epoxidized soybean oil as a secondary plasticizer. The glass transition temperature of plasticized CDA was observed at $50^{\circ}C$ lower than virgin CDA and the incorporation of 5% ESO also resulted in the additional $20^{\circ}C$ decrease in the $T_g$. The tensile properties and modulus of plasticized CDA were better than commercial PP and PLA. The aerobic biodegradability of CDA in controlled compositing condition resulted in 90% of degradation during 60 days.