• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.11
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• pp.1422-1426
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• 2008

The purpose of this study was to test characteristics between normal and autistic children via comparison of nutrient intakes, hair mineral, blood free radical, and serotonin contents. A total of 50 children aged 3-9 were divided into two main groups of normal control children (n=22) and autistic children (n=28) tested by child psychiatrist. The nutrient intakes by 24-hour recall method were no significantly different between the two groups. The concentrations of toxic mineral, such as cadmium (Cd) and lead (Pb) in hair of autistic children were significantly higher, while concentration of antioxidant mineral (Cu, Zn, Fe) was lower than that of normal children. The autistic children had significantly higher concentrations of blood free radical than that of normal children. No significant difference was observed in serotonin concentration between the two groups. Our results suggest a possible role of increased toxic mineral and free radical, both of which may be relevant to the pathophysiology of autism in children with developmental delay.

• The Transactions of the Korean Institute of Power Electronics
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• v.5 no.4
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• pp.358-369
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• 2000

Shielded metal arc welding machines with AC transformer have been widely used for thin-plate welding applications. Because of being bulky, heavy and of tap-changing property, so the SMAW's are changing to new power electronic circuits such as inverter circuit in order to reduce the system size and also to improve the welding performances at input output sides. The PWM inverter arc welding machine with diode rectifier has better output welding performances but it is has the plentiful harmonics and the lower input power factor. To solve these problems, input current-controlled scheme is considered for PWM inverter arc welding system, and then total input power factor is maintained to be more than 99%. Also a new combined control is proposed which can control both instantaeous welding output voltage and current under constant power condition, and as a result the variations of instantaneous current and voltage can be reduced to very narrow range in the V-I curve relationship, and hence the variance of welding current and voltage become so reduced. In addition the spatter generated during welding process is greatly reduced up to 70%. And the overall effiency can be improved up to 10%, which becomes higher when the load is lower.

• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.5
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• pp.651-656
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• 2007

Fish-frames which are left after obtaining fillets or muscle during fish processing, consist of useful food components such as muscle, collagen, calcium, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). This study was carried out to prepare snack using flatfish frame and also to elucidate food component characterization of the snack. The results of heavy metal and volatile basic nitrogen (VBN) content suggested that flatfish frame was a suitable material for preparing snack. The optimal addition ratio of flatfish frame to mix was 3% for preparing snack according to the results of VBN content, water activity and sensory evaluation. The major fatty acids of the snack with 3% flatfish frame (SFF) were 16:0 and 18:0 as saturates, 18:1n-9+7 as monoenes, and 18:2n-6 and 18:3n-3 as polyenes, while EPA and DHA were contained in small amount SFF. Total amino acid content (9,281.9 mg/100 g) of the SFF was higher than that of the snack without flatfish frame (7,791.3 mg/100 g) and the major amino acids were aspartic acid, glutamic acid, proline and leucine. The calcium and phosphorus contents of SFF were 492.3 mg/100 g and 270.3 mg/100 g, respectively. The Ca/P of SFA was 1.82 which is a good ratio for the absorption of calcium. The SFF was superior in total amino acid, calcium and phosphorus contents compared to the snack without flatfish frame.

• Journal of Korean Society of Environmental Engineers
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• v.30 no.10
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• pp.1034-1038
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• 2008

Degradative Solidification/Stabilization(DS/S) is a modification of conventional Solidification/Stabilization(S/S) that incorporates degradative processes for organic contaminant destruction with the low cost of conventional S/S. Inorganic contaminants are immobilized and chlorinated organic contaminants are destroyed by DS/S treatment. In this study, a DS/S using cement/slag/Fe(II) systems as binder was investigated to assess its effectiveness in degrading chloroform(CF) and methylene chloride(MC) contained in hazardous liquid wastes. The initial concentration of CF was 0.26 mM, 1.0 mM, 8.4 mM, 25 mM and 42 mM and Fe(II) was 200 mM. The result showed that degradation of CF in various concentration was in one kind reaction as pseudo-first-order and 95% of 0.26 mM initial concentration of CF was removed in five days. 50 mg/L of heavy metal was added in order to accelerate the rate of degradation of MC and initial concentration of MC was 3.50 mM however, degradation did not occur in system. Thus additional studies needed for degradation of MC and more studies on other reaction pathways products will help elucidate reaction mechanisms and pathways for chlorinated methanes in cement/slag/Fe(II) systems.

• Korean Journal of Environmental Biology
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• v.25 no.4
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• pp.289-296
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• 2007

Di-(ethyhexyl) phthalate (DEHP), commonly used as a plasticizer for manufacturing flexible vinyl products, has been the topic of extensive research, especially concerning endocrine disrupting properties. Metallothionein (MT) is a low molecular weight (6,000$\sim$7,000 Da), cysteine-rich (22$\sim$23%), metal-binding protein and is known to be induced by extrinsic factors such as chemical agents and stresses. Some of the known function of MT include detoxification of heavy metals and alkylating agents and neutralization of free radicals. Nonetheless, the definitive physiological function of MT are still unknown. This study was carried out to investigate the effects of DEHP on the ultrastructural changes and the expression of MT of the rat liver. The rats were orally intubated with either corn oil (experimental control) or 0.5 mg, 1.5 mg and 4.5 mg DEHP kg$^{-1}$ day$^{-1}$ in 0.5 mL of corn oil for 15 days before sacrificing and sampling. DEHP induced mild ultrastrctural changes of some cell organelles such as rough endoplasmic reticulum, mitochondria, lysosomes and peroxisomes in the rat liver treated with DEHP. In the respect of immunogold labelling and Western blotting, MT expression of the liver tissue was up-regulated by DEHP. In conclusion, DEHP has effects on the ultrastructures and hepatic function for MT expression in rat.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2006.04a
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• pp.247-252
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• 2006

오염 퇴적물내 중금속의 방출과 이에 따른 생이용성(bioavalability)은 기존의 가역 평형관계로써 설명하기에 불충분한 것으로 알려져 있다. 최근 연구결과에 의하면 이러한 탈착 저항성을 설명하기 위한 비가역적 모델에 의해 퇴적물내 중금속의 탈착저항성 부분이 존재함이 밝혀졌다. 탈착저항성에 대해서는 아직 충분한 규명이 이루어지지 않았으나, 오염물질의 노화(aging)에 의해 일단 탈착저항성을 띠게 되면 생이용성(bioavailability)이 감소되는 것으로 알려져 있다. 본 연구에서는 노화(aging)가 연안 퇴적물 내 납과 카드뮴의 흡/탈착 특성에 미치는 영향을 알아보기 위해 연속 탈착실험과 biphasic 탈착모델을 적용함으로써 납과 카드뮴의 탈착저항성을 규명하고자 하였다. 그리고 연속 추출 실험을 통해서 노화(aging)에 따른 퇴적물 내 납과 카드뮴의 흡착 기작을 규명하고자 하였다. 연속탈착 실험 결과 시간이 경과함에 따라 탈착저항성부분의 크기가 증가하였으며, 연속추출 실험 결과 납의 경우 carbonate fraction에서 추출된 납이 가장 많았으며, 노화(aging) 따라 exchangeable fraction에서 추출된 납이 감소하는 반면 reducible, organic material, residual fraction에서 추출된 납의 양이 증가하였다. 카드뮴의 경우 가장 많은 양이 추출된 단계는 exchangeable fraction이였으며, organic material fraction에서는 카드뮴이 추출되지 않았다. 노화(aging) 따라 reducible fraction과 residual fraction에서의 추출량이 증가하는 경향을 보였으나 그 양은 매우 적은 것으로 나타났으며, 노화(aging)에 따른 exchangeable fraction과 carbonate fraction에서의 추출량은 큰 변화가 없었다. 대해서는 북한지역의 분포상황을 밝혔다.것을 알 수 있었으며, 크롬과 비소의 경우는 초기에 많이 용출되고, 구리의 경우는 꾸준히 용출되는 것을 알 수 있었다. 3년 된 통나무집이 8년 된 통나무집보다. 용출양이 더 컸으며, 이는 CCA성분이 초기에 많이 용출된다는 것을 의미한다. 억제 효과를 나타내었고 Hep3B에서는 부탄을 분획물 (1 mg/mL)에서 82%의 비교적 높은 성장억제효과를 나타내었다.as a "front" and "back". Thus, Germany′s private space may face a genuine public space and street, which is rare in the Korean housing. Although the layout of indoor space in the korean housing tends to be open, such an openness may be outstanding in living and dining spaces, kitchen and various accesses to rooms. In the case of Germany, such indoor spaces are usually closed to each other. Thus corridors act to separate these spaces. Such differences are analysed to be due to the different perceptions of interpersonal and socio-cultural attributes as intra-family and inter-neighbor relationships or communications. 알 수 있었다.도 질소와 인산처럼 토양지지대가 있는 경우가 낮은 함량을 유지하였다.pe from the daily life, to fantasize and daydre

• Korean Journal of Soil Science and Fertilizer
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• v.14 no.4
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• pp.242-249
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• 1982

Effects of lime and ameliolating materials on decreasing available soil cadmium were studied, applying the amendments to Cd pre-and post-treated soils. Soil sttreated with Cd were placed in pots and kept under field moisture condition, summer through winter in 1981. The results of soil analysis made 40 to 60 days after the Cd treatment are as follows ; 1. Greater amount of Cd was extracted by 0.1N-HCl or 2% Citric acid than N-AcNH4 solution. More Cd was dissoluted by 0.1-HCl than 2% Citric acid. No Cd was extracted by pure water. Showing a wide variance in the amount of extractable Cd among treatments (amendments), the $N-AcNH_4$ solution seemed to be the most effective extracting solution of available soil cadmium. 2. Calcium hydroxide was the most effective materials in reducing $N-AcNH_4$ extractable Cd, followed by calcium carbonate and calcium silicate. 3. Superphosphate is also effective in reducing exchangeable cadmium. The reduction seemed to be attributed to the precipitation of cadmium phosphate. 4. The exchangeable cadmium by $N-AcNH_4$ was large in the soil pH range of 6.0 and 6.5, and it decreased as the soil pH became far apart from these values. The decrese of exchangeable Cd at low pH seemed to be related to the increase of $Mn^{+{+}}$ and that at the high pH to the precipitation as Cd-hydroxide.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.4 no.2
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• pp.144-154
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• 1999

Masan Bay is highly polluted by the discharge of large quantities of effluents from the industrial complex and domestic sewage of Masan City, Southeast Korea. Surface sediments from 9 stations were used for geochemical and foraminiferal analyses in order to investigate foraminiferal response to sedimentary pollution in the Bay. The heavy metal concentrations in sediments are relatively higher than those in Kyeonggi Bay and Daesan area, west coastal region of Korea. Zn, Cd, Pb, and As are more concentrated than in world average shale, indicating that the municipal and industrial effluents cause sediment contamination. Responses of benthic foraminifera to the sedimentary pollution effect document a degree of pollution in Masan Bay. The species number and diversity in Masan Bay had lower values than those in Gadeog Channel. In Masan Bay, agglutinated foraminifera are abundant and calcareous foraminiferal tests were frequently pyritized. Eggerella advena and Trochammina pacifica dominated at levels of pollution and could be opportunistic species. These data will provide a baseline for future assessments of environmental quality in Masan Bay.

• Journal of Animal Environmental Science
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• v.15 no.1
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• pp.75-84
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• 2009

This study was carried out to determine the effect of swine liquid manure on the rice growth and yield in 2006. Field experiment was conducted under variable application rates; 100%, 120%, 150%, 180% N level of slurry based on 11 kg N 10a recommended amount of nitrogen. The experimental sites were located at Cheorwon in Gangwondo area. The results were summerized as follows; In the plot treated with swine liquid manure of 150% and 180% N levels, the plant height and tillers were higher, and the color of leaf was darker than that of 100% N level of swine liquid manure. Rice yield in the plot applied with 120% N slurry level was increased at 11%, but those of 150%, 180% N-level application plots were reduced 10, 19% compared to 100% N level, respectively. Rice quality of the 100 and 120% application plots of swine liquid manure was significantly better than those of 150 and 180% levels of application plots. Total nitrogen content in rice plant after harvesting was increased with increasing levels of swine liquid manure. The content of K in the soil was accumulated in plot treated with 150%, 180% slurry compared to control plot. The heavy metal contents in soils were not increased treated with swine liquid manure. The density of bacteria was low in the application plot of 180%N of liquid swine manure. The bacteria/fungi ratio was highest in 120% N level of liquid manure treatment.

• Korean Journal of Food Science and Technology
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• v.35 no.5
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• pp.764-768
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• 2003

Resveratrol is natually occurring phytoalexin compounds produced by grape berries, peanuts, and their products in response to stress such as fungal infection, heavy metal ions or UV irradiation. The objective of this study was to develop a reliable high-performance liquid chromatographic method for the quantitative determination of trans-resveratrol in grape and its products. The trans-resveratrol was separated isocratically on Nucleosil 100-5 C18 column, using a mobile phase containing acetonitrile : water (40 : 60, v/v), detected by UV detector at 306 nm and the flow rate was 0.3 mL/min. Under this analytical condition, the recoveries of trans-resveratrol in grape, wine, and grape juice were 92.35, 104.72, and 91.08, respectively. Limit of detection in grape, wine, and grape juice were 14.5 ng/g, 3.62 ng/mL, and 4.02 ng/mL. Also, limit of quantitation in grape, wine, and grape juice were 14.8 ng/g, 3.69 ng/mL, and 4.10 ng/mL. Assay values of 32 grape varieties, 9 wines, and 9 grape juices were ranged from trace amount to $207.1\;{\mu}g/100\;g$, from 5.4 to $275.7\;{\mu}g/L$, and from 63.3 to $751.6\;{\mu}g/L$, respectively.