• Journal of Life Science
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• v.13 no.2
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• pp.197-205
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• 2003

We detested waterborne enteric viruses from the raw water and tap water in Busan metropolitan city by the total culturable virus assay of EPA standard method. According to the results of survey from July 2001 to November 2002, thirteen out of twenty one in raw water samples were positive (61.9%) for enteric viruses and all of the treated water and tap water samples were negative. The enteric viruses in raw water were mainly distributed through the summer to the earl y winter, suggesting the seasonal characteristics of virus distribution in water The titer of enteric viruses per 100 liters of the raw water was ranged from 1.92 to 9.70 MPN by TCVA-MPN program. The isolated viruses were identified as either human poliovirus type 1 or enteroviruses by the immunofluorescent assay.

• Fisheries and Aquatic Sciences
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• v.25 no.2
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• pp.76-89
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• 2022

The Lophius litulon liver was used as raw material for the extraction of fish oil via various extraction methods. The extraction rate by water extraction, potassium hydroxide (KOH) hydrolysis and protease hydrolysis were compared and the results revealed the protease hydrolysis extraction had a higher extraction rate with good protein-lipid separation as observed by optical microscope. Furthermore, subsequent experiments determined neutrase to be the best hydrolytic enzyme in terms of extraction rate and cost. The extraction conditions of neutrase hydrolysis were optimized by single-factor experiment and response surface analysis, and the optimal extraction rate was 58.40 ± 0.25% with the following conditions: enzyme concentration 2,000 IU/g, extraction time 1.0 h, liquid-solid ratio 1.95:1, extraction temperature 40.5℃ and pH 6.5. The fatty acids composition in fish oil from optimized extraction condition was composed of 19.75% saturated fatty acids and 80.25% unsaturated fatty acids. The content of docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) were 8.06% and 1.19%, respectively, with the ratio (6.77:1) surpassed to the recommendation in current researches (5:1). The results in this study suggest protease treatment is an efficient method for high-quality fish oil extraction from Lophius litulon liver with a satisfactory ratio of DHA and EPA.

• The Journal of the Korea institute of electronic communication sciences
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• v.15 no.6
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• pp.1195-1200
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• 2020

The DOM (: Digital Optical Method), which measures the turbidity of chimney smoke, is a method of calculating the turbidity by setting the area to be measured and the contrast area using a low-cost digital camera that can be easily obtained. However, it is difficult to measure clouds and white smoke in a cloudy sky. In this paper, we develop a background sky type model that can represent the background sky and classify the type by periodically photographing it with a digital camera to solve this problem. In addition, based on the model, we develop a filter to optimize white smoke image and prove its excellence through experiments.

• The Korean Journal of Pesticide Science
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• v.9 no.2
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• pp.159-165
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• 2005

A sensitive derivatization method by using the TFE/TFAA as derivative reagent is proposed for the determination of acidic herbicides in water, by using this method, method detection limits are improved by 10 times and sample volumes are decreased by 5 times compared with other methods such as U.S. EPA and SPEED 98. And also, in order to suggest higher creditable standard operating procedure (SOP), intra- and inter-lab validation test carried out by four laboratories include our lab. The results of intra and inter-lab validations in same experimental conditions show good linearity in given range of concentrations as a $0.1{\sim}10.0$ ng/ml, and range of accuracies and precisions show $-20.5{\sim}12.2$ bias%, $0.55{\sim}24.48%$ (for intra-lab validation) and $-6.66{\sim}0.80 bias%$, $1.92{\sim}13.86%$ (for inter-lab validation), respectively.

• Journal of Environmental Impact Assessment
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• v.29 no.2
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• pp.93-111
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• 2020

Health Impact Assessment (HIA) in Korea is conducted for specific development projects within Environmental Impact Assessment (EIA) system. However, as HIA is being carried out in the implementation stage of the development project, it sometimes has failed to take proper actions despite the significant adverse health impact. Considering an environment conflict regarding adverse health impact in developing industrial complex and the current application of HIA in EIA system, it is necessary to come up with an adequacy evaluation in the industrial complex development considering health impact. This study proposes an adequacy evaluation method considering health impact for the industrial complex development and embodies the method by applying it to actual cases. Referring to methodologies of US EPA's CalEnviroScreen 3.0 and US ATSDR's Public Health Assessment, this study proposed using indicators divided by community characteristic, background exposure and development burden as an adequacy evaluation method to consider health impact. Five indicators for community characteristic, three indicators for background exposure and seven indicators for development burden were selected through literature survey, and the weights for each indicator were calculated through Analytic Hierarchy Process's survey of experts related to HIA. Through a pilot application in the three government-led industrial complex development projects, the method was further elaborated by clarifying the evaluation data and subdividing the evaluation criteria for each indicator. Adequacy criteria of plan considering health impact could be presented in three ways to be linked to the government's policy stance on the industrial complex development criteria of total score, criteria of total score and community characteristic score, and criteria of total score and community characteristic allowed by development burden.

• Bulletin of the Korean Chemical Society
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• v.27 no.5
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• pp.649-656
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• 2006

The proposed head-space supercritical fluid extraction (SFE) methodology as an alternative to an existing conventional procedure was explored for the determination of organochlorine compounds in aqueous matrix. In this study, polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) were utilized as target analytes. To enhance the recovery efficiency, the factors such as the $CO _2$ density, the extraction time, and the extraction mode were investigated. Furthermore, the analytical procedures and the results obtained were compared with those provided by the conventional method (the U.S. EPA method 8080). Under the optimized conditions, i.e., a combination of static with dynamic SFE mode at 2,000 psi and 40 ${^{\circ}C}$, the head-space SFE methodology gave equivalent or better to the conventional method in recovery efficiencies with clear advantages such as simple sample treatment and fast analysis time as well as reduced solvent and reagent consumption.

• Korean Journal of Soil Science and Fertilizer
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• v.41 no.5
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• pp.324-329
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• 2008

A coal mine drainage sludge(designated as CMDS) is mainly generated during physicochemical treatment or electrical purification of the drainage abandoned mine that include dissolved heavy metal. To understand the possibility of an application of the dehydrated CMDS as the landfill cover medium of hygienic a reclaimed ground, an laboratory experiment was performed to investigate the physicochemical and geoengineering characteristics of the dehydrated CMDS. To improve the geoengineering characteristics of the dehydrated CMDS, the liquid limit, plasticity limit test, compaction method test, strength test, and hydraulic conductivity test ware performed with the lithification material mixed sludge. When the mixed ratio of the sludge and the lithification material was more than 1:06, the compaction method was A method, the moisture content less than 33.5%, the strength of mixed sludge was $8.2kg\;cm^{-2}$, the hydraulic conductivity was $2.7\times10^{-6}cm\;sec^{-1}$, the sludge was up to the landfill standard of US Environmental Protection Agency (US EPA).

• Korean Journal of Fisheries and Aquatic Sciences
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• v.46 no.6
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• pp.708-716
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• 2013

Changes in the proximate composition, lipid classes, and fatty acids were studied in chub mackerel Scomber japonicus and Japanese jack mackerel Trachurus japonicus muscles cooked using a frying pan, oven, and microwave oven. The moisture content was high in the raw samples (chub mackerel 65.5%, Japanese jack mackerel 60.5%) and decreased with cooking, especially in the frying pan method (chub mackerel 49.2%, Japanese jack mackerel 49.8%). In contrast, the protein, lipid and ash contents increased significantly with cooking in chub mackerel muscle (P<0.05). However, the lipid content of Japanese jack mackerel muscle showed no significant difference between the samples using the three cooking methods and the raw sample. The dripped lipid contents from the cooked muscles showed the highest levels in the frying pan samples and the lowest levels in the microwave oven samples. The percentage of non-polar lipid (NL) in the total lipid content was over 95% in the muscle lipids (10.43-21.86 g/100 g sample). Prominent fatty acids were 16:0, 18:1n-9, 22:6n-3 (docosahexaenoic acid, DHA), 16:1n-7 and 20:5n-3 (eicosapentaenoic acid, EPA) in both fish muscles and dripped lipids. There was no change in the EPA level in any of the fish muscles, by any cooking method. The percentage of DHA in the muscle of chub mackerel showed the lowest level in the frying pan sample and the highest level in the microwave oven and raw samples, and an intermediate level in the oven sample. However, the percentage of DHA in the Japanese jack mackerel muscle was not significantly different between the various cooking methods. From these results, the microwave oven and oven cooking methods showed relatively low levels of dripped lipid content and loss of n-3 PUFA compared with the frying pan cooking method.

• Analytical Science and Technology
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• v.13 no.1
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• pp.55-65
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• 2000

In this study, we collected the tap water that treated from water plant in Seoul, Incheon, Taejon, Kwangju, Taeku and Pusan and supplied each house. The sampling period was June and September, 1997. The concentration of THMs formed by chlorination in drinking water was determined with the purge and trap method with GC/MSD recommended by the us EPA 542.2 method. Chloroform is the most of THMs (47.43%~93.11%) and the content order is bromodichloromethane > chlorodibromomethane > bromoform. In Incheon, Taejon, Kwangju, Taeku and Pusan, the content of bromodichloromethane, chlorodibromomethane and bromoform was higher than Seoul. But, in June and September, the concentration of THMs in six cities is not over Korea Drinking Water Regulation $100{\mu}g/L$. The calculated human exposure for each substances were chloroform $6.14{\times}10^{-4}mg/kg/day$, bromodichloromethane $1.01{\times}10^{-4}mg/kg/day$, chlorodibromomethane $0.29{\times}10^{-4}mg/kg/day$, bromoform $0.01{\times}10^{-4}mg/kg/day$ and THMs $7.98{\times}10^{-4}mg/kg/day$.

• Journal of Korean Society for Atmospheric Environment
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• v.20 no.E1
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• pp.29-33
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• 2004

In environmental studies, decisions are often made on the analytical data indicating certain contaminants as being 'detected' or 'non-detectible.' Since detection limits are analytical method specific, one has to first review the concepts and definitions associated with analytical method systems and specifications. In this study, the experimental analytical values for a series of low level standards (for an ionic species) were used as an example to estimate two different method detection limits (MDL). The scores of EPA's MDL and Pallesen's MDL determined by real analytical scores are 0.0575 and 0.0561 mg/L, respectively for our nitrate data. These scores determined by two different MDL models are roughly similar, while there are apparent differences between two methods with respect to statistical and systematical procedure. However, determination of MDL for one's laboratory provides some practical applications which helps to assure one's regulating authorities that one's measured scores are accurate.