• Korean Journal of Food Science and Technology
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• v.32 no.2
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• pp.277-283
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• 2000

This study was conducted to investigate the effect of ozone treatment on the growth and pesticide-residual contents of soybean sprouts during cultivation. Total weight and length of the soybean sprouts treated by 0.3 ppm ozone water for 30min during soaking of soybean increased 27% and 19% higher than those of control group, respectively. But 27% of root weight decreased. No major differences in growth state were observed between the treatments during soaking and watering with ozone water, and watering with ozone water. Pesticide residues in soybeans treated with carbendazim, captain, diazinon, fenthim, dichlorvos and chlorpyrifos ranged from 4.75 to 8.35 ppm. The pesticides in soybean sprouts by the treatment of soaking and watering with water for 5 days, those by 0.3 ppm ozone-water watering, and those by soaking and watering with 0.3 ppm ozone water were destroyed to $85{\sim}99$, $89{\sim}100$ and $94{\sim}100%$, respectively. The order of degradation ratio in the pesticides was captan>dichlorvos>fenthion>carbendazin>diazinon>chlorpyrifos.

• Journal of the Korean GEO-environmental Society
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• v.17 no.5
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• pp.37-46
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• 2016

In order to determine the variability of environmental characteristics of lightweight air-foamed soil using marine clay according to freezing-thawing and soaking conditions, unconfined compressive strength of the lightweight air-foamed soil samples made by changing the amount of cement under curing conditions of outdoor low temperature, underground or indoor wetting were observed. Compressive strength was not increased under freezing-thawing (temperature range of $-9.1^{\circ}C{\sim}17.2^{\circ}C$) regardless of the amount of cement but the more cement using, it was increased rapidly by underground curing conditions within 30 cm beneath ground level. Therefore, it is necessary to install insulation layer cutting off exterior cold air after construction of lightweight air-foamed soil in condition of freezing-thawing. Bulk density was increased too small under the long-time soaking condition, it tended to decrease rapidly when samples were dried up and had below 6% of water contents. But variability of compressive strength and bulk density was very small for preventing drying and keeping its wet state. The lightweight air-foamed soil that installed beneath ground water level or covered by soil can be evaluated as a long-term reliable construction material.

• Journal of the Korean Geotechnical Society
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• v.37 no.11
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• pp.83-92
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• 2021

In this study, effective porosity measurement, electron microscope (SEM) observation, X-ray diffraction analysis (XRD), slaking, swelling, and unconfined compression strength according to water immersion were analyzed to evaluate the properties of mudstone with high porosity in Pohang. As a result of the test for 16 square samples (5 cm), the effective porosity was 14.67% on average, higher than porosity of general mudstone, and electron microscope observation confirmed that the porosity was actually high. As a result of X-ray diffraction analysis, the swelling clay mineral content was 2.3~4.1%, which was lower than the results of previous studies in Pohang. The slake durability index was 37.73~87.73%, showing low to medium durability, which was lower than the results of previous studies. It was confirmed that the swelling property rapidly expanded to 1.79~1.82% of maximum swelling strain in the major axis direction for 30 minutes. As the properties of decreasing the unconfined compression strength according to water immersion, the samples rapidly weathered after 10 minutes of water immersion, and the strength decreased. It was confirmed that the results of previous studies related to mudstone in Pohang were different. This is judged to be due to the high porosity of mudstone in study.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.29 no.5C
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• pp.207-215
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• 2009

Cemented soils or concrete are usually cured under moisture conditions and their strength increases with curing time. An insufficient supply of water to cemented soils can contribute to hydration process during curing, which results in the variation of bonding strength of cemented soils. In this study, by the consideration of in situ water supply conditions, cemented sand with cement ratio less than 20% is prepared by air dry, wrapped, moisture, and underwater conditions. A series of unconfined compression tests are carried out to evaluate the effect of curing conditions on the strength of cemented soils. The strength of air dry curing specimen is higher than those of moisture and wrapped cured specimens when cement ratio is less than 10%, whereas it is lower when cement ratio is greater than 10%. Regardless of cement ratio, air dry cured specimens are stronger than underwater cured specimens. A strength increase ratio with cement ratio is calculated based on the strength of 4% cemented specimen. The strength increase ratio of air dry cured specimen is lowest and that of wrapped, moisture, and underwater cured ones increased by square. Strength of air dry cured specimen drops to maximum 30% after wetting when cement ratio is low. However, regardless of cement ratio, strength of moisture and wrapped specimens drops to an average 10% after wetting. The results of this study can predict the strength variation of cemented sand depending on water supply conditions and wetting in the field, which can guarantee the safety of geotechnical structures such as dam.

• 한국문화재보존과학회:학술대회논문집
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• 2003.09a
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• pp.48-54
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• 2003

• 한국문화재보존과학회:학술대회논문집
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• 2007.05a
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• pp.31-32
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• 2007

• 보존과학연구
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• s.5
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• pp.179-188
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• 1984

본문은 Conservation of Water logged Wood(1979, Netherlands National Commission for UNESCO)중의 "The Use of Polyethylene glycol for the Treatment of Waterlogged wood-its Past and Future(Dr.C.Pearson)" 및 "The Conservation of ship wrecks by impregnation with Polyethylene glycol (Dr.J.deJong)"을 역편한 것임.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.10a
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• pp.288-288
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• 2017

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2007.05a
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• pp.194-195
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• 2007

• Proceedings of the Korean Society of Food and Cookery Science Conference
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• 2005.05a
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• pp.106-106
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• 2005