• Fisheries and Aquatic Sciences
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• v.13 no.3
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• pp.244-253
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• 2010

The quality of marine sediments from the industrialized coastal areas of Korea (Ulsan Bay, Masan Bay, and artificial Lake Shihwa) was investigated using a bacterial bioluminescence toxicity test. Sediment toxicity results were compared with the levels of chemical contamination (trace metals, organic wastewater markers, acid volatile sulfides, total organic carbon). Effective concentration 50% (EC50) of sediments ranged from 0.014 to 1.126 mg/mL, which is comparable to or lower than values in contaminated lakes, rivers, and marine sediments of other countries. Sediment reference index (SRI) ranged from 13 to 1044, based on the EC50 of the negative control sample. Mean average SRI values in Masan Bay and Lake Shihwa were approximately 8 and 9 times as high as that in Ulsan Bay, indicating higher sediment toxicity and greater contamination in the two former regions. Sediment toxicity were strongly associated with the concentrations of some chemicals, suggesting that this test may be useful for determining potential chemical contamination in sediments.

• Korean Journal of Clinical Laboratory Science
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• v.36 no.2
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• pp.269-273
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• 2004

Squamous cell carcinoma(SCC) associated antigen is a subfraction of TA-4, a tumor-associated antigen first described by Kato and Torigoe in 1977. TA-4, obtained from squamous cell carcinoma cancer tissue of the uterine cervix, has been characterized as a glycoprotein with a molecular weight of approximately 45,000 daltons. SCC antigen has been studied in other squamous cell malignancies including lung, esophagus, head and neck, anal canal, and skin. SCC antigen is shed naturally through sweat, saliva and other body fluids. Contamination of specimens, tray, bead dispenser or other accessories with sweat, saliva or aerosols can cause falsely elevated values. To reduce the possibility of contamination, gloves should be worn in all phases of assay preparation, and when handling specimens, accessories or reagents that will be used in SCC and Thyroid function test(TFT).

• The Journal of Engineering Geology
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• v.25 no.4
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• pp.577-585
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• 2015

Contamination of soil due to an oil spill influences its subsequent behavior. An investigation was conducted to study the effect of oil viscosity on compaction characteristics, coefficient of permeability, and shear strength. Water permeability was also determined by using Kerosene, Engine oil, and Crude-oil as contaminants. The test results indicate that the compaction characteristics are influenced by oil contamination. Direct shear test was conducted to investigate the effect of oil in the pore space in sandy ground. angle of internal friction of sand (based on total stress condition) decreases due to presence of oil within the pore spaces in sand.

• Journal of Ecology and Environment
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• v.37 no.2
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• pp.41-51
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• 2014

This study investigated the ability of Bothriochloa bladhii (Retz.) S.T. Blake (Poaceae), Cyperus ligularis L. (Cyperaceae), Commelina erecta L. (Commelinaceae), Mariscus umbellatus (Rottb.) Vahl (Cyperaceae), Fimbistylis miliacea L. (Cyperaceae) and Torulinium odoratum L. (Cyperaceae) to clean up various levels of used motor oil (UMO) contaminated soils. The plants were grown in 2 kg garden soils treated to 0%, 1%, 5% and 10% levels of UMO contamination. The plant growth parameters, chlorophyll contents and dry weight of test plants were measured. The phytoremediation ability of these test plants were assessed by measuring the uptake of hydrocarbons in terms of total hydrocarbon content (THC) as well as their percentage degradation values. There was significant (P < 0.05) reduction in leaf chlorophyll contents and dry weights of the test plant species planted in UMO contaminated soils. THC as well as the percentage uptake (or degradation) of hydrocarbons were both lowest in C. ligularis but highest in T. odoratum in all cases. The phytoremediation potential of test plants was highest in soils contaminated with 5% UMO. Based on the results of this study, all test plants with the exception of C. ligularis were potentially capable of undertaking phytoremediation. However, B. bladhii and T. odoratum proved most effective in the uptake and degradation of UMO.

• Korean Journal of Clinical Laboratory Science
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• v.46 no.1
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• pp.1-11
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• 2014

This research has been performed by our own investigation, also cooperated with Health and Sanification Division and each of district offices in Busan metropolitan city. After choosing, we collected water samples five times for microbiological examination. As a result of investigating in 160 water samples from urban areas, we could detect 88 cases of Vibrio spp. Furthermore, there were four cases exceeding the acceptable limit of aquarium water (100,00/mL) and another four cases exceeding the limit of Coliform group (1,000 below/100 mL). As a result of investigating that we performed for 271 cases of water samples from coastal areas from April to November, we could detect 130 cases of vibrio species and 10 cases of Coliform group. After performing 17 kinds of antibiotic susceptibility test for 41 cases of isolated Vibrio parahaemolyticus, 27 cases showed tolerance to Amplicllin (AM), all of 31 cases showed intermediate resistance only to Cefazolin (CF) but had sensitivity to the rest of them. As a result of performing antibiotic susceptibility test, serum test and PFGE gene analysis on each 10 pair of Vibrio parahaemolyticus detected concurrently from intake-pipe water and, aquarium water, we couldn't get data showing that they are clearly same species in three kinds of test. In addition, UV sterilization, Ozonization and so on. Based on our research, intake pipe didn't have a problem with microbiological contamination so we are sure that the germ came from supplied fish had caused that kind of contamination. For effective management, UV sterilization or Ozonization which can be handled consistently should be adopted in aquarium.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 2000.06a
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• pp.24-33
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• 2000

The effect of particulate contamination on friction and wear between a negative-pressure picoslider / tri-pad nanoslider and laser-textured disk was studied. Particles of different concentration were injected at the head-disk interface consisting of disks with various textures and slider types at different speed. Durability increased and coefficient of friction decreased as the disk speed increased in a contaminated environment. Frictional characteristics and durability in the data zone were better for those of the laser-textured zone. It was also found that durability of head-disk interface (HDI)decreased as the particle concentration increased. The interface durability with a picoslider was better than that with a nanoslider at any condition in a contaminated environment. Based on the test results, mechanisms were proposed to explain the reasons why durability with a picoslider was superior to that with a nanoslider.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2015.11a
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• pp.156-157
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• 2015

The safety concern of slipping on floors in South Korea has come to the fore as a social problem, but the occurrence of such accidents has not decreased. Slip and fall accidents have several causes, but they are especially common when there is soapy water on the floor during a shower or a bath. Despite this situation, it can be said that there is a lack of standards on surface contamination materials used in floor slip resistance testing. Therefore, in this study, we conducted a survey to identify the components and quantity of soapy water that actually results from a user taking a shower, and the standardization of contamination materials. Based on the results of this experiment, we provide a surface contamination material that can replace the soapy water used in floor slip resistance testing.

• Tribology and Lubricants
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• v.16 no.6
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• pp.469-476
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• 2000

The effect of particulate contamination on the friction and wear between a negative-pressure picoslider/tri-pad nanoslider and laser-textured disk was studied. Particles of different concentration were injected at the head-disk interface consisting of disks with various textures and slider types at different speed. Durability increased and coefficient of friction decreased as the disk speed increased in a contaminated environment. Frictional characteristics and durability in the data Bone were better than those in the laser-textured zone. It was also found that durability of head-disk interface (HDI) decreased as the particle concentration increased. The interface durability with a picoslider was better than that with a nanoslider at any condition in a contaminated environment. Based on the test results, mechanisms were proposed to explain the reasons why durability with a picoslider was superior to that with a nanoslider.

• Proceedings of the Korean Geotechical Society Conference
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• 2000.11a
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• pp.415-418
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• 2000

There has been a steady increase in geoenvironmental engineering projects where geotechnical engineering has been combined with environmental concerns. Many of these projects involve some investigation on contaminant around unplaned waste landfill. In this study, investigation and test on contamination characteristics of wastes dumped at municipal site were carried out. Testing wastes were sampled at this site. Sampled wastes were divided into waste itself and soil to analysis the characteristics of waste and soil. As a result of this study, the concentration of soil and waste were investigated. And measured concentration were compared with related concentration criteria.

• 한국정보디스플레이학회:학술대회논문집
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• 2006.08a
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• pp.18-20
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• 2006

The panels were fabricated to characterize the contamination of Magnesium Oxide (MgO) thin films by phosphors and ion bombardments in AC-PDPs. Forty-six inch WVGA panels of the surface and vertical discharge type were manufactured. The experiment was designed to investigate the relationship between the MgO thin films and phosphor contamination caused by ion bombardments in a plasma environment to produce a life time test. The contamination of MgO thin films by phosphors was investigated by way of X-ray photoelectron spectroscopy (XPS).