• Korean Journal of Fisheries and Aquatic Sciences
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• v.33 no.6
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• pp.524-528
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• 2000

Effect of food additives on the heat sensitivity of listeria monocytogenes H-12 inoculated into Pollack surimi was investigated and also confirmed the effectiveness of various decontamination method such as tap water washing, chlorination, ultraviolet irradiation and heat treatment haying been applied on cooking utensils. Food additives such as polyphosphate, chitosan, and potassium sorbate increased heat sensitivity of t monocytogenes H-12 and polyphosphate showed the strongest synergistic effect. The tested strain was not detected from stainless steel and plastic cutting board contaminated with $10^4{\~}10^5/cm^2$ of L monocytogenes H-12 after tap water washing for 10 seconds or 1 minute, but washing effect was not found in wooden cutting board. The chlorination of stainless steel and plastic cutting board for 10 seconds with $5{\~}50 ppm$ solution eliminated all cells of the contaminated strain, however any change of the viable cell count was not observed in the chlorination of wooden cutting board, W irradiation on stainless steel and plastic cutting board for 5 minutes with 15 W above 30 cm eliminated the contaminated strain, but the tested strain was still found after 60 seconds of irradiation on wooden cutting board. The treatment of hot water on all used cutting boards for 10 seconds at $70^{\circ}C$ resulted in complete loss of viability of the contaminated strain.

• Tribology and Lubricants
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• v.27 no.5
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• pp.275-280
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• 2011

Automotive wheel bearing grease helps to reduce stresses and prevent wear of wheel bearings. But it is easily contaminated by water and other contaminants. In this study, we investigated the property change of automotive wheel bearing grease under water contamination. The result showed that some properties such as dropping point, work penetration and oxidation stability were not influenced by water content. However, most of properties such as work stability, water washout characteristics, leakage tendency, oil separation, evaporation loss and rust protection became worse after water was added. This is thought that added water makes the interaction weak between thickener and base oil of grease.

• Water for future
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• v.35 no.5
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• pp.51-59
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• 2002

In recent years the human impact on the environment becomes increasing lift threatening, calls for the better management of resources. In field of water quality of river flow, the best way to conserve water quality is specific efforts to control the pollutant loadings and treat the loadings in the basin to reduce the discharge of pollutant loadings to river. But in general the water quality influenced by the dam discharge. Especially in dry season, it is more dominant way to improve the water quality which contaminated with the pollutant loadings from the basin. The dam discharge amounts of the 2 dams in the Keum River that maintain the down stream water quality were estimated for the year of 1999, 2001, 2006, 2011, in case of irrigation and non-irrigation seasons. The pollutant loadings for the basin are estimated with the planning of treatment plants construction schedule for every sub-basins. The river flow rates were considered low flow as 2.33 year low flow and 10 year low flow. The QUAL2E model was used as a tool of simulation.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2001.04a
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• pp.140-143
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• 2001

The packed column experiments were conducted with commercial Jumunjin sand(SOM content : 0.01 %) and a field soil(SOM content : 0.08 %) in order to understand the effects of water content and soil organic matter(SOM) on the transport of gaseous ozone in unsaturated soil contaminated with phenanthrene. Water content and SOM content were artificially controlled. As water content increased, earlier breakthrough was observed in the beginning of BTC of ozone, because direct contact of gaseous ozone with SOM and phenanthrene was prevented by water film formed between soil particles and gaseous ozone. The total removal of phenanthrene in Jumunjin sand was not affected by water content which was more than 99% at different water content(4.4, 8, 17.3%). However, the removal in field soil at water content 6.5 % and 20 % was 98% and 80 %.

• Toxicological Research
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• v.18 no.2
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• pp.107-116
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• 2002

Arsenic (As) is a ubiquitous element found in several forms in foods and water. Although certain foods, such as marine fish, contain substantial levels of organic arsenic forms, they are relatively low in toxicity compared to inorganic forms. in contrast, arsenic in drinking water is predominantly inorganic and highly toxic. Chronic ingestion of arsenic-contaminated drinking water is therefore the major pathway posing potential risk to human hearth. since the early 1990s in Bangladesh ozone, arsenic exposure has caused more than 7,000 deaths and uncounted thousands shout symptoms of long-term arsenic poisoning. Significant portion of world populations are exposed to low to moderate levels of arsenic of parts per billion (ppb) to hundreds of ppb. As a consequence, the World Health Organization (WHO) and U.S. environmental health agencies, such as the Environmental Protection Agency (EPA) made arsenic their highest priority. Recently, the WHO, European Union (EU), and US. EPA lowered an acceptable level of 10 ppb for arsenic in drinking water In this article, various health effects of arsenic in drinking water were reviewed and the current status for risk assessment to regulate arsenic in drinking water was discussed.

• Journal of Dental Rehabilitation and Applied Science
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• v.18 no.3
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• pp.217-224
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• 2002

The purpose of this study was to evaluate the influence of saliva contamination on the resin bonding of the etched metal retainers. The test samples were made of Verabond, and divided into 3 groups. Retainers in group1 had normally etched metal surfaces. Retainers in group2 had normally etched metal surfaces which were saliva-contaminated for 30 seconds and cleaned with streaming, luke-warm for 1 minute and dried thoroughly. Retainers in group3 had normally etched metal surfaces which were saliva- contaminated for 30 seconds and dried thoroughly without water-cleansing. Each 3 group specimen was watched on SEM. A resin core, 5mm in diameter and 6mm in length, was made of Panavia using Teflon mold on the each specimen. These 3 groups were tested to evaluate shear bond strength, using universal testing machine. The results were as follows : 1. The shear bond strength showed no significant difference between group1 and group2. 2. The shear bond strength showed significant difference between group1 and group3. 3. The shear bond strength significant difference between group2 and group3. 4. Scanning electron microscope photographs of group1 and group2 showed no signs of contamination but of group3 showed somewhat contaminated.

• Journal of Soil and Groundwater Environment
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• v.15 no.5
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• pp.1-7
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• 2010

Electrokinetic technology was applied to remediate Cu, Pb and As-contaminated paddy soil. Removal of metal is highly dependent on the processing fluid during electrokinetic treatment. Tap water, NaOH, $HNO_3$, $Na_2EDTA$, and citric acid were evaluated as the processing fluids to enhance metal removal. Cu and Pb were transported toward cathode, however, it did not removed from soil section, while 56.6% of As was removed at a acidic condition. The strong acidic condition with nitric acid as a processing fluid enhanced the desoprtion of As from soil surface. However, longer operation time is needed to get the higher removal of Cu and Pb, and the acidification of soil after electrokinetic treatment should be solved.

• Journal of Soil and Groundwater Environment
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• v.16 no.4
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• pp.31-37
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• 2011

The feasibility study of soil flushing was investigated to remediate lubricant oil and zinc contaminated railway soil. In this study, mixed washing agents of surfactant and inorganic acid/base were used for the simultaneous removal. The mixed washing agent of non-ionic surfactant and HCl removed 15% of the lubricant oil and 40% of zinc, respectively. Alkaline-enhanced soil washing process increased the removal of lubricant oil up to 40%. This is because alkaline solution reduced the interfacial tension between water phase and lubricant oil phase due to the soap formation reaction. To simulate in-situ soil flushing for the remediation of railroad-related contamination, two dimensional soil flushing was carried out based on the results of batch soil washing. In the soil flushing, the removal efficiencies of lubricant oil and zinc were 34% and 16%, respectively. Even though the removal efficiency was low, the mixed washing agent can remove metal and lubricant oil simultaneously.

• Journal of Korea Soil Environment Society
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• v.3 no.3
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• pp.109-116
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• 1998

Treatability tests of a soil washing device were performed for the remediation of eil-contaminated soil. The contaminant-containing soil with water was first fed into a oc-current screw conveyor and then into a counter-current washer. Surfactant was introduced into the washer and feeding soil was continuously separated on the basis of #40 mesh at the same time. A washing efficiency of 97.9% was achieved by the the soil washing device optimized.

• Journal of Environmental Science International
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• v.5 no.6
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• pp.771-778
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• 1996

The sediment in the highly contaminated Gamjeon brook was collected, mixed with the raw material of the tile, and then the commercial tile was produced using the mixture. The concentrations of the heavy metals in the mixture-before and after the tile was produced-were analyzed and the effects of the acid solution on the produced tile were examined. The production of the tiles was successful and the result of heavy metal analysis showed that the concentration of Fe was the highest and that of Cd was the lowest The amount of heavy metal in the sediment - the raw material of the tile mixture was more than that of the produced tile. The elution concentration of the heavy metal by the acid solution(pH : 4 - 7) was low and the quality of the produced tile was better than the commercial tile. The result of this study suggested that the contaminated sediment was removed to produce good tiles, therefore the water pollution and soil pollution were reduced.