• Korean Journal of Soil Science and Fertilizer
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• v.44 no.6
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• pp.1080-1084
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• 2011

Predictive model for estimating total contents of cadmium (Cd) and lead (Pb) was developed by stepwise multiple-regression analysis using chemical properties and extractable contents of metal in paddy soil adjacent to abandoned mines in 2009 and 2010. Soil properties, e.g. pH, electrical conductivity (EC), organic matter (OM), available phosphorus ($P_2O_5$), and exchangeable cations (i.e. Ca, Na, K, Mg) were measured. Total contents of Cd and Pb as well as extractable contents of metals were analyzed by ICP-OES. Results showed that the total and extractable contents were estimated to be 3.55 and $0.27mg\;kg^{-1}$ in Cd and 83.38 and $24.32mg\;kg^{-1}$ in Pb on the average. From stepwise analysis, it was found that the contents of extractable Cd, Zn, Cu, as well as exchangeable Na were significantly influenced on estimation of the total contents of Cd in soil. Moreover, it also showed that the contents of extractable Pb, Zn, and Cu significantly affected estimation of the total contents of Pb in soil. More significant relationship between estimated and measured value in total contents of Pb was observed than those of Cd ($R^2$=0.87, p<0.0001). This demonstrates that extractable contents of metal are influenced more on estimation of total contents of Cd and Pb in soil than soil properties.

• Journal of the Korean GEO-environmental Society
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• v.15 no.12
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• pp.25-34
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• 2014

The objective of this study was to investigate the removal characteristics and the elimination mechanism of heavy metals in Acid Mine Drainage (AMD) using spherical-type porous Zeolite-StarFish ceramics (porous ZSF ceramics) packed in a continuous column reactor system. The average removal efficiencies of heavy metals in AMD were Al 98.7, As 98.7, Cd 96.0, Cu 89.1, Fe 99.5, Mn 94.4, Pb 96.3 and Zn 80.8 % during 110 days of operation time. The average removal capacity of porous ZSF ceramics for heavy metals were measured to be Al 21.76, As 1.52, Cd 1.27, Cu 3.41, Fe 44.83, Mn 3.48, Pb 2.36 and Zn $3.76mg/kg{\cdot}day$. The analysis results of mechanism using SEM, EDS and XRD exhibited that the porous ZSF ceramics could act as a multi-functional ceramics for the removal of heavy metals in AMD through the reactions of precipitation, adsorption and ion-exchange. The experimental results of column reactor system displayed that the porous ZSF ceramics would be a consistently efficient agent for the removal of heavy metals in AMD for a long term.

• Economic and Environmental Geology
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• v.44 no.5
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• pp.359-372
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• 2011

TA26 seamount, which is located at south part of Tonga arc, occurs widely hydrothermal plume and is area that sampled hostrock, hydrothermal ore and hydrothermal alteration rock for this study. Hostrocks are basalt and basaltic andesite. Altered rocks by hydrothermal solution consists of plagioclase, pyroxene, pyrite, ilmenite, amorphous silica, barite, smectite, iron sulfates, Fe-Si sulfates and Fe silicates. Gains and losses of major, trace and rare earth elements during wallrock alteration suggest that $K_2O$(+0.04~+0.45 g), $SiO_2$(-6.52~+10.56 g), $H_2O$(-0.03~+6.04 g), $SO_4$(-0.46~+17.54 g), S(-0.46~+13.45 g), total S(-0.51~+16.93 g), Ba(-7.60~+185078.62 g), Sr(-36.18~+3033.08 g), Ag(+54.83 g), Au(+1467.49 g), As(-5.80~+1030.80 g), Cd(+249.78 g), Cu(-100.57~+1357.85 g), Pb(+4.91~+532.65 g), Sb(-0.32~+66.59 g), V(-113.58~+102.94 g) and Zn(-49.56~+14989.92 g) elements are enriched from hydrothermal solution. Therefore, gained(enriched) elements(($K_2O$, $H_2O$, $SO_4$, S, total S, Ba, Sr, Ag, Au, As, Cd, Cu, Pb, Sb, V, Zn) represent a potentially tools for exploration of sea-floor hydrothermal deposits from the Tonga arc.

• Korean Journal of Environmental Agriculture
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• v.2 no.2
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• pp.78-82
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• 1983

Some physico-chemical properties and heavy metal contents of up-land and paddy field soils on the drainage-basin of Daejeon Cheon and Yoodeung Cheon in Daejeon area were investigated. The average contents (and the range) of Pb was 6.75 ppm (2.33-11.65 ppm), Cr; 1.77 ppm (0.58-4.0 ppm), Cd; 0.7pprn (0.09-1.83 ppm), Cu; 9.96 ppm (t-19.36 ppm), and Zn; 19.99 ppm (2.38-47.9 ppm) in up-land soil, and Pb; 7.77 ppm (t-15.5 ppm), Cr; 1.91 ppm (t-9.38 ppm), Cd; 0.21 ppm(t-2.05 ppm), Cu; 11.17 ppm (t-21.96 ppm), and Zn; 18.0l ppm (1.65-40.0ppm) in paddy field soil, respectively.

• Journal of Life Science
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• v.17 no.7 s.87
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• pp.948-955
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• 2007

Neutrophils play a key role as a first line of defense and are known to acquire the characteristics of dendritic cells (DCs) under the appropriate conditions. The spontaneous apoptosis of neutrophils was delayed by treatment with 4-(2-aminoethyl) benzensulfonylfluoride (AEBSF), a serine protease inhibitor. AEBSF inhibited both caspase-3 and serine protease activities, whereas ZVAD-fmk, a pancaspase inhibitor, inhibited only caspase-3 activity. The life span of neutrophils was prolonged up to 5 days by AEBSF in the presence or absence of granulocyte macrophage colony stimulating factor(CM-CSF). DC surface markers, such as CD80, CD83, and MHC class ll were not expressed on neutrophils treated with AEBSF alone. CM-CSF failed to prolong the survival time of neutrophils up to3 days but increased the expression levels of DC markers on neutrophils in the presence of AEBSF. Expression levels of DC markers were the highest on neutrophils treated with CM-CSF and AEBSF for 3 days. AEBSF and CM-CSF-treated neutrophils stimulated proliferation of T cells in the presence of a superantigen, Staphylococcal enterotoxin B (SEB) but produced $interferon-{\gamma}$ ($IFN{\gamma}$) in the absence of SEB. These results suggest that the inhibition of serine protease activity prolonged the life span of human neutrophils and combined treatment of neukophils with CM-CSF and serine protease inhibitor induced differentiation of neutrophils into DC-like cells.

• Clean Technology
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• v.26 no.4
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• pp.263-269
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• 2020

Zeolite was synthesized hydrothermally using the water-treatment sludge, and the effects of various synthesis parameters like reaction temperature, reaction time, and Na2O/SiO2 molar ratio on the crystallization of zeolite were investigated. Crystal structure, physical property, and thermal stability of zeolite crystals were characterized by X-ray powder diffraction, FTIR spectroscopy, BET nitrogen adsorption, and TGA measurements. The removal efficiencies of nitrogen in ammonia, heavy metal ions, and TOC were calculated to evaluate zeolite's adsorption capacity. The primary chemical composition of water-treatment sludge was 28.79% Al2O3 and 27.06% SiO2. The zeolites were synthesized by merely employing the water-treatment sludge as silica and alumina sources without additional chemicals. Zeolite crystals synthesized through the water-treatment sludge were confirmed as an A-type zeolite structure. Zeolite A had the highest crystallinity obtained from a gel with the molar composition 2.1Na2O-Al2O3-1.6SiO2-65H2O after 5 h at a temperature of 90 ℃. The specific surface area of zeolite obtained was 55 ㎡ g-1, which was higher than commercial zeolite A. The removal efficiency of nitrogen in ammonia was 68% after 3 h of reaction time, while the removal efficiencies of Pb2+ and Cd2+ ions were 99.1% and 99.3%, respectively. These results indicate active ion exchange between Pb2+ or Cd2+ ion and Na+ ion in the zeolite framework. The adsorption experiments on the different zeolite addition conditions were performed for 3 h with 300 ppm humic acid. Based on the results, TOC's highest efficiency was 83% when 5 g of zeolite was added.

• Journal of Food Hygiene and Safety
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• v.36 no.4
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• pp.281-288
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• 2021

This study was conducted to analyze and compare the concentrations of heavy metals in 430 different products of 20 types of herbal medicines available in the domestic market in Korea by Graphite Furnace-Atomic Absorption Spectrometry (GF-AAS) and automated mercury analyzer. The accuracy for lead (Pb), arsenic (As), cadmium (Cd), and mercury (Hg) was in the range 92.67-102.56%, and the precision was 0.21-6.00 relative standard deviation (RSD%), which was in compliance with the Codex acceptable range. Furthermore, the Food Analysis Performance Assessment Scheme (FAPAS) quality control (QC) material showed a recovery range of 96.7-102.0% and 0.33-4.93 RSD%. The average contents (㎍/kg) of Pb, As, Cd, and Hg in herbal medicines were 254.9 (not detected (N.D.)-2,515.2), 171.0 (N.D.-2,465.2), 99.2 (N.D.-797.1), and 6.0 (N.D.-83.6), respectively. Based on the quantitative analysis results, the heavy metal contents of 20 types of herbal medicines distributed in Korea are within the acceptable range according to the standards issued by the Ministry of Food and Drug Safety (MFDS). By using the manufacturer of herbal products as the standard for QC, the Pb, As, Cd, and Hg contents were investigated in the packaging process just before distribution to determine the actual conditions of residual heavy metals in herbal medicines. Thus, these result may contribute to monitoring the QC of herbal medicines distributed in Korea and could provide basic data for supplying safe herbal medicines to the public.

• Product Safety
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• s.40
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• pp.83-85
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• 1995

업소용 노래방의 붐이 가정으로 옮겨져 각 가정에서 보유하고있는 TV나 오디오등과 조합하여 노래방의 효과를 충분히 낼 수 있는 가정용노래방의 보급이 확산되어 가고 있다. 노래방기는 CD파에 곡을 수록하는 방식과 칩에 수록하는 방식이 있는데 금번에는 칩방식을 대상으로 시판중인 국내 6개사 제품을 구입하여 전기적인 안전성, 전기적성능, 영상 및 오디오출력등 17개 항목에 대하여 평가한 결과 노래방기의 중요한 항목인 안전성과 영상 및 오디오출력에는 모두 합격하

• Proceedings of the Korean Society for Information Management Conference
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• 1995.08a
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• pp.83-86
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• 1995

본 연구에서 구축된 멀티미디어 도서관 정보시스템은 대학도서관을 기본 모형으로 하여 설계하였다. 이 시스템은 7 개의 모듈 즉 참고문헌제공 전문가시스템, 학술지 브라우징, 멀티미디어 데이타베이스, 텍스트 데이타베이스(온라인 열람목록, OPAC), 외부데이타베이스(온라인/CD-ROM/인터넷 데이터베이스), 도서관 이용안내, 시스템이용법으로 구성된다. 시스템의 구현 환경은 IBM 컴퓨터 466DX2/Dp을 사용하고 시스템 개발도구로는 하이퍼텍스트 기능이 첨가된 멀티미디어 저작 도구인 멀티미디어 툴북을 이용하고 이용자 인터페이스는 메뉴방식을 채택하였다.

• 기계와재료
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• v.21 no.2
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• pp.74-83
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• 2009

유리나 금속판재와 같은 저가의 기판상에 박막재료를 코팅하여 제조하는 박막형 태양전지는 대면적 양산화를 통한저가격화 실현이 가능한 차세대 태양전지로 업계의 많은 관심을 끌고 있다. 본 기고에서는 박막형 태양전지로 분류되는 실리콘 박막태양전지, CIGS 태양전지, CdTe 태양전지, 염료감응형 태양전지 등의 기술 현황과 그 핵심 소재기술을 소개한다. 차세대 성장산업으로 기대되는 박막태양 전지 시장에서 국내 업체의 기술자립과 국제경쟁력 확보를 위해서는 핵심소재에 대한 원천기술 확보와 소재 및 설비의 국산화가 절실히 요구되는 시점이다.