• Journal of the Korean Society of Food Science and Nutrition
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• v.28 no.1
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• pp.22-27
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• 1999

This study was performed to investigated the contamination levels of harmful heavy metals were sampled from Aug. 1 to Aug. 31, 1997, at 9 areas in Cheonbuk area. The heavy metal contents were determinated by ICPS(Inductively Coupled Plasma Spectrometer) method. The levels of total lead, cadmium, aluminum, iron and copper were determined and the results were summarized as follows: The minimum and maximum values(ppm) of 9 areas of Carassius auratus were Pb: 2.03~6.19, Cd: 0.06~ 0.76, Al: 8.84~23.5, Zn: 10.68~48.71, Cu: 0.60~1.51ppm. Among the five heavy metals contents, the highest was zinc and the lowest was cadmium. The results showed that the contents of Pb, Cd, Al, Zn and Cu in Carassius auratus were lower than the FAO/WHO maximum allowance.

• Journal of the East Asian Society of Dietary Life
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• v.9 no.2
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• pp.169-176
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• 1999

The purpose of this study was to investigate the relationships of dietary nutrients and serum heavy metals in college women living Choong-Nam area of Korea. The mean age, height, weight, and BMI were 22.9years, 158.74cm, 53.39kg, and 21.71kg/$m^2$ respectively. The mean daily energy intake was 85.9% of RDA for Koreans. The ratio of energy from carbohydrate, fat, and protein was 61:23:16. And the daily vitamin A, B$_2$, Ca were 90%, 78%, 60% of RDA for Korea, respectively. The mean serum levels of Pb, Cd, Cr were 0.190, 0.005, 0.025$\mu\textrm{g}$/$m\ell$, respectively. The serum Cd was significantly different with dietary carbohydrate(p＜0.05). And the serum Cr was significantly different with dietary protein intake(p＜0.05), phosphorus(p＜0.01), potassium(p＜0.05). respectively.

• Journal of the Korean Society of Safety
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• v.24 no.4
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• pp.22-27
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• 2009

In this paper, the minuteness structure, piezoelectric, and dielectric characteristics of $0.95{Pb(Sb_{1/2}Nb_{1/2})_{0.02})_{0.02}(Ni_{1/3}Nb_{2/3})_{0.13}(Zr_{0.48}Ti_{0.52})_{0.85}}O_3+0.05Pb(CO_{1/2}W_{1/2})O_3+0.3%$ $MnO_2+0.3wt%$ CuO ceramics has been systematically investigated as a function of the sintering temperature after manufacturing the specimens with a general method. This study will be very helpful as basic data for developing ceramic materials, More study in a soon time for improving stability of temperature, effect of adds and stability and reality of frequency with improved production condition for specimens will give a powerful potentiality as a applied material of dielectric ceramics.

• Journal of Welding and Joining
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• v.23 no.2
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• pp.18-22
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• 2005

전자패키징을 포함한 마이크로시스템 패키징의 재료 및 어셈블리 기술에 관련한 도전성 접착제 및 접속 기술을 개략적으로 소개하였다. 이와 같은 도전성 접착제 및 접속 기술은 종래 사용되어 왔던 Pb 솔더의 환경, 인체에의 악영향 등으로 인한 무연(Pb-free) 솔더의 개발과 함께 차세대 솔더의 대체 재료 및 접속 기술로서 주목받고 있다. 도전성 접착제는 이미 반도체 집적회로를 기판에 접합하는 등 널리 사용되고 있지만 최근 도전성 접착제에 대한 수요와 시장 규모가 증가하는 추세이며 더 나아가 그 응용 범위가 점차로 확대되어 가고 있다. 특히 국제적 규약에 의한 무연 솔더의 사용이 의무화됨에 따라 전기적 접속성, 열 도전성, 접합성 등 기본 솔더에 버금가는 특성을 확보하기 위한 새로운 재료의 개발 및 공정에 대한 연구가 필요하다. 선진국에서는 이러한 기술의 필요성을 인식하고 많은 연구 인력, 시설 및 정보 공유 등을 통해 활발한 투자와 연구개발이 진행되고 있다. 이에 한국에서도 국제 경쟁력을 향상시키고 차세대 첨단 산업 분야의 신기술 확보를 위해 체계적인 연구 활동을 위한 노력이 절실히 요구된다.

• Environmental Analysis Health and Toxicology
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• v.31
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• pp.21.1-21.7
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• 2016

Objectives The present study analyzes metal contamination in sediment of the East Kolkata Wetlands, a Ramsar site, which is receiving a huge amount of domestic and industrial wastewater from surrounding areas. The subsequent uptake and accumulation of metals in different macrophytes are also examined in regard to their phytoremediation potential. Methods Metals like cadmium (Cd), copper (Cu), manganese (Mn), and lead (Pb) were estimated in sediment, water and different parts of the macrophytes Colocasia esculenta and Scirpus articulatus. Results The concentration of metals in sediment were, from highest to lowest, Mn ($205.0{\pm}65.5mg/kg$)>Cu ($29.9{\pm}10.2mg/kg$)>Pb ($22.7{\pm}10.3mg/kg$)>Cd ($3.7{\pm}2.2mg/kg$). The phytoaccumulation tendency of these metals showed similar trends in both native aquatic macrophyte species. The rate of accumulation of metals in roots was higher than in shoots. There were strong positive correlations (p <0.001) between soil organic carbon (OC) percentage and Mn (r =0.771), and sediment OC percentage and Pb (r=0.832). Cation exchange capacity (CEC) also showed a positive correlation (p <0.001) with Cu (r=0.721), Mn (r=0.713), and Pb (r=0.788), while correlations between sediment OC percentage and Cu (r=0.628), sediment OC percentage and Cd (r=0.559), and CEC and Cd (r=0.625) were significant at the p <0.05 level. Conclusions Bioaccumulation factor and translocation factors of these two plants revealed that S. articulatus was comparatively more efficient for phytoremediation, whereas phytostabilization potential was higher in C. esculenta.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2002.04a
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• pp.262-262
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• 2002

2001년 12월과 2002년 1월에 걸쳐 조간대 환경에 위치하는 어느 해양사격장 중위에서 일정한 간격으로 표층(<5 cm) 해양퇴적물(총22개소)과 해양생물체(굴; 총10개소)를 샘플링하고, Pb, Cu, Cd, Zn를 위시한 중금속원소의 공간적 농도 분포와 생흡수도(bioavailability)를 분석 고찰하였다. 본 논문에서는 예비 연구 결과를 간단히 소개한다. 해양퇴적물에 대한 전함량 분석, 0.1N HCl에 의한 부분 분석 및 BCR법에 의한 연속추출 분석 결과는 다음과 같다. Pb, Cu, Cd, Zn을 위시한 중금속은 대체적으로 점오염원인 사격장으로 갈수록 전함량 및 부분함량이 높아지는 경향을 보여주었다. 사격장 주변에서 가장 중요한 오염물질로 알려져 있는 Pb는 오염원 주변에서만 높은 함량을 보여주어, 해양 환경 하에서 이동도( 및 생흡수도)가 비교적 낮은 것으로 나타났다. 반면, Cu, Cd, Zn의 경우에는 보다 넓은 영역에 걸쳐 퇴적물 내의 부화(enrichment)가 인지되어 연구지역의 갯벌 환경에 의미있는 정도로 영향을 미치고 있는 것으로 나타났다. 이 곳의 생물체(굴) 역시 Pb에 대해서는 낮은 흡수도(-값의 생농축계수)를 나타낸 반면, Cu, Cd, Zn에 대해서는 의미있는 생흡수도를 나타내었다. BCR 연속추출법에 의한 퇴적물 중금속의 존재형태 해석 결과를 보면, fraction 1(F1; exchangeable+acidic phase) 및 fraction 2(F2; reducible phase)의 기여도가 지배적이고, 또한 오염원으로 갈수록 그 기여도는 점차 증가됨을 나타내었다. 특이하게도 유기물과의 친화력이 높은 것으로 알려진 Cu 역시 F1과 F2에 대하여 높은 함량을 나타내어 오염원으로부터의 Cu의 확산을 지시하였다. 외국에 비하여, 그동안 국내에서는 사격장 주변의 자연환경변화에 관하여 연구된 결과가 거의 전무하였다. 본 연구 결과는, 이와 유사한 사격장 주변 환경에서의 중금속 분포와 거동 특성에 대하여 종합적인 모니터링(즉, 체계적인 환경지구화학적 조사ㆍ연구)이 시급함을 시사해 주고 있다.

• Journal of the Korean Society of Food Science and Nutrition
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• v.22 no.4
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• pp.484-488
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• 1993

The heavy metal contents in Carassius auratus, that were sampled from Nov.1 to Nov. 31, 1991 at 6 areas in Joenlabuk-do. The mercury contents was determined by mercury analyzer using the combustion Goldamal-gamation method. The arsenic contents were determined by spectrophotometry using silver diethyl ditiho carbamate method. The contents of other heavy metals were determined by inductively coupled plasma spectrometer method. The levels of total mercury, arsenic, cadmium, lead, cupper, manganes, and zinc were determined and the results were summarized as follows : The 6 areas over all range(ppm) were Hg : 0.0167~0.0407, As : N.D.~0.0018, Cd : 0.1256~0.1935, Pb : 0.3536~0.6593, Cu : 0.2094~0.3792, Mn : 2.9059~6.9335, Zn : 14.3095~48.1615ppm. Among the seven heavy metals contents, the higest was zinc and the lowest was arsenic. The results show that contents of Hg As, Cd, Pb, Mn and Zn in Carassius auratus were lower than the FAO/WHO maximum allowance.

• Nutritional Sciences
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• v.2 no.2
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• pp.88-92
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• 1999

The purpose of this study was to study the intake of heavy metals such af arsenic, lead and cobalt and the relationship of dietary heavy metals with serum iron, topper, and zinc, which play important roles in hematopoiesis, in healthy college women living in Choongnam Korea, where we have detected heavy metals (As, Pb, Co) in some marine products in previous studies. The nutritional status of the subjects (35 women) was evaluated by anthropometric measurements, 24-hr dietary recall for 3 days. And 3-day diets (by weighing method) and blood were collected to analyze As, Pb, Co, Fe, Cu, Zn, Hb, Hct, and MCHC. The mean age, height, weight, and BMI were 20 years, 158 cm, 55 kg and 22.42 kg/$m^2$, respectively. The mean daily energy intake was 85.85% of RDA for Koreans. The ratio of energy from carbohydrate, protein, and fat was 60 : 24 : 16. The mean daily intake of heavy metals (As, Pb, Co) was 1.77 mg/day, 75.21 $\mu$g/day and 21.12 $\mu$g/day. And the mean daily intake of iron, copper, and Zinc concentrations were 97, 68, and 92% of normal values. The mean serum heavy metals (As, Pb, Co) were 16.14 $\mu$g/dl, 4.32 $\mu\textrm{g}$/dl and 0.02 $\mu$g/dr, respectively Mean blood levels of Fe, Cu, Zn, Hb, Hct, and MCHC were at normal levels. Dietary heavy metals except Co were not significantly different from serum Fe, Cu, Zn and Hb, Hct, and MCHC. However, there was a tendency toward lower serum concentration of Fe, Hb, Hct, and MCHC in the subjects with higher heavy metals (As) intake. Among heavy metals, only dietary Co showed a significant negative correlation with Hb (p< 0.001) and Hct (p < 0.001).

• Journal of Radiation Protection and Research
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• v.22 no.3
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• pp.143-151
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• 1997

As the pulse heights from a NaI(Tl) detector vary with the temperature of the measuring environment a significant change in temperature may affect the energy calibration of the spectrometer. The auto-adjustment of the channel corresponding to a pulse heights can be achieved by introducing an external reference source to compensate the temperature dependency of pulse heights, but unfavorable increases of the Compton continuum are caused due to the external source. In this study, the total absorption peaks dominant in the typical environmental gamma spectrum-239 keV from $^{212}Pb$, 351 keV from $^{214}Pb$, 1460 keV from $^{40}K$ and 2614 keV from $^{208}Tl$ for examples - were used as reference in the correction of energy calibration. With these peaks, the program to calibrate the energy of the s spectrum was developed using Microsoft Visual Basic language. The program developed here was applied to the environmental spectra measured at intervals of 30 minutes in the temperature range of from $-20^{\circ}C$ to $10^{\circ}C$ to demonstrate the validity and applicability. As a result of the test, the correction scheme appeared to be effective in the temperature changes encountered in the usual environment.

• Journal of Pharmaceutical Investigation
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• v.22 no.3
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• pp.219-227
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• 1992

The influence of phenobarbital (PB) pretreatment (75 mg/kg/day, i.p. for 4 days) on the pharmacokinetics of diltiazem (DTZ) and its metabolite, desacetyldiltiazem (DAD), was investigated in rats. DTZ was injected via femoral (3 mg/kg) or portal (10 mg/kg) vein to the control and PB-pretreated rats. DAD was also injected separately via femoral (3 mg/kg) vein to both groups of rats. The intrinsic hepatic plasma clearance of DTZ was found to be significantly increased (6.8-fold) by the PB pretreatment. However, the fraction of an intravenous DTZ dose converted to DAD $(F_mi)$ was only slightly (6%) increased and calculated metabolic rate constant of DTZ to DAD was not affected by the pretreatment. On the other hand, plasma free fraction of DTZ was increased (1.8-fold) from $4.24{\pm}0.25%$ to $7.45{\pm}0.54%$ by the pretreatment. However, the l.8-fold increase in the free fraction of DTZ would not explain the 6.8-fold increase in the hepatic intrinsic clearance of DTZ. Therefore, the increase in either the hepatic blood flow or the metabolism other than to DAD was expected as the probable mechanism(s) of the increased hepatic clearance of DTZ. Sequential metabolism of DAD to further metabolites, however, would be a more potential cause of the apparently unchanged metabolism of DTZ to DAD by the PB-pretreatment.