• Journal of Nutrition and Health
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• 제26권6호
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• pp.743-757
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• 1993

This study was undertaken to investigate the effects of dietary Fe and Cu levels on Pb accumulation of Pb poisoned rats. 80 male Sprague weaning Dawley rate weighing 80-90g were divided into 8 groups(Pb groups: LFLCPb-low Fe, low Cu and Pb group, LFACPB-low Fe, adequate Cu and Pb group, AFLCPb-adequate Fe, low Cu and Pb group, AFACPb-adequate Fe, adequate Cu and Pb group, without Pb gorups: LFLC-low Fe, low Cu and without Pb grooup, LFAC-low Fe, adequate Cu and without Pb group, AFLC-adequate Fe, low Cu and without Pb group, AFAC-adequate Fe, adequate Cu and without Pb group) according to Pb administration (0, 500ppm in drinking water) and Fe and Cu levels(Fe :6ppm, 40ppm, Cu : 0.5ppm, 0.8ppm) for 12 weeks. The food intake, body weight, gain, and FER of Pb groups were significantly lower than those of without Pb groups(p<0.01, p<0.001, p<0.001). The weights of liver in Pb groups were significantly lower than that of adequate Fe and Cu group in without Pb group(AFAC) (p<0.001). The Cu contents of liver in Pb groups were significantly lower than that of AFAC (p<0.01). The liver Pb accumulation of LFLCPb was significantly higher than those of LFACPb, AFLCPb, AFACPb(p<0.05). The serum Pb content of LFLCPb was significantly higher than those of LFACPb, AFLCPb, AFACPb(p<0.05). The levels of Hb, and Hct, of 12 weeks in Pb poisoned rats were lower than those of 8 weeks, in other words, long term Pb poisoned rats were affected more serious on hematoopoiesis. The fecal excretions of Fe and Cu in Pb groups were significantly higher than those of without Pb groups(p<0.001, p<0.001). The urinary Fe and Cu excretions were significantly higher than those of AFAC(p<0.001, p<0.001). There were significant differences between Pb groups and without Pb groups according to dietary Fe and Cu levels. So, dietary levels of adequate Fe and Cu were effective to reduce Pb accumulation in rats. It were showed that the decrease of food intake, FER, body weight gain, serum level of Fe and Cu in Pb groups than those of without Pb groups. And the increase of liver Pb accumulation, serum Pb levels, fecal and urinary Fe and Cu excretions were showed in Pb groups than those of without Pb groups by long term lead poisoning. Otherwise, adequate Fe and Cu administrations in Pb groups have preventive effects on the Pb poisoned rats.

• 한국전기전자재료학회논문지
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• 제14권5호
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• pp.423-429
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• 2001

PbS, CuS and (Pb,Cu)S thin films were chemically deposited on glass from alkaline baths containing lead acetate, copper chloride, thiourea and triethanolamine. The deposition, optical, resistivity and thermal electric properties of these films were studied. PbS thin films showed a hexagonal structure and CuS thin films showed amorphous. The crystalline of (Pb,Cu)S thin films was obtained by heat treatment at 200$\^{C}$ and the deposition ratio of Pb to Cu showed 7:3. The energy gap of PbS, CuS and (Pb,Cu)S thin films were 1.7, 2.1 and 2.4 eV, respectively. Sheet resistance of PbS thin films was less affected on thermal annealing, but hose of (Pb,Cu)S and CuS thin films were more reduced about 3 orders of magnitude. All of those thin films indicated p type semiconductor in temperature ranging 30$\^{C}$ to 150$\^{C}$.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2004년도 하계학술대회 논문집 Vol.5 No.1
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• pp.543-546
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• 2004

The melting temperature and critical temperature(Tc) of $YBa_2Cu_3O_x$ with deferent content impurities of PbO and $BaPbO_3$ were studied. When the PbO was used as addition in $YBa_2Cu_3O_x$, although the melting point could be reduced, the superconductivity(the transition width, ${\Delta}T_c$) became poor. From the XRD pattern of the sintered mixture of $YBa_2Cu_3O_x$ and PbO it was known that there is a reaction between $YBa_2Cu_3O_x$ and PbO, and the product is $BaPbO_3$. In the process of the reaction the superconducting phase of $YBa_2Cu_3O_x$ was decreased and in the sample $BaPbO_3$ became the main phase. Therefore the superconductivity was reduced. $BaPbO_3$ was chosen as the impurity for the comparative study. The single phase BaPbO3 was synthesized by the simple way from both mixtures of $BaPbO_3$ and PbO, $BaPbO_3\;and\;PbO_2$. Deferent contents of $BaPbO_3$(10%, 20%, 30%) were added in the $YBa_2Cu_3O_x$. By the phase analysis in the XRD patterns it was proved that there werenot reactions between $YBa_2Cu_3O_x$ and $BaPbO_3$. When $BaPbO_3$ was used as impurity in $YBa_2Cu_3O_x$ the superconductivity was much better than PbO as impurity in $YBa_2Cu_3O_x$. But the melting point of $YBa_2Cu_3O_x$ with $BaPbO_3$ could not be found when the temperature was lower than $1000^{\circ}C$ in the DTA measurement.

• KSBB Journal
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• 제13권4호
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• pp.444-448
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• 1998

Biosorption of Pb and Cu was evaluated for 23 species of marine algae collected from a Korean coast. Among a variety of species for biosorbent potential, Hypnea charoides showed the highest capacity for Pb. An adsorption equilibrium was reached in about 2 hr for Pb and 30 min for Cu. The uptake capacity was 192.8 mg Pb/g biomass and 256 mg Cu/g biomass, respectively. The adsorption parameters for Pb and Cu were determined according to Langmuir model. With an increase in pH value, more negative sites are becoming avaliable for adsorption of pH and Cu, thus the removal of Pb and Cu increases at alkaline conditions. The selectivity of mixture solution shows the uptake order of Pb>Cu>Cr>Cd. When Ca concentration increases in Pb solution, Pb was selectively adsorbed.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2000년도 추계학술대회 논문집
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• pp.13-16
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• 2000

(PbS)$_{1-x}$ -(CuS)$_{x}$ thin films(x=0, 0.5, 1) were grown on glass substrates by using a chemical bath deposition method. The molecular ratio of Pb to Cu for the PbS-CuS thin films(x=0.5) was measured about 7:3 by using EDX and XRF. The resistivity of non-annealed (PbS)$_{1-x}$ -(CuS)$_{x}$ thin films was about 10 $\Omega$ . cm. However, after annealing, the resistivity of PbS showed a little change, while PbS-CuS and CuS significantly decreased in the range of 0.002 to 0.005$\Omega$.cm. PbS was p-type and CuS was n-type.-type.

• 한국분말재료학회지
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• 제5권3호
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• pp.220-226
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• 1998

W-12.8wt%Cu-7.2%Pb powders were milled at room temperature and $-100^{\circ}C$ to investigate the mechanical alloying behavior of immiscible W-Cu-Pb system and the effect of milling temperature on the extent of alloying and microstructural refinement. W-Cu-Pb powder reached steady state after further extended milling due to Pb addition, compared to the W-Cu system. The cryomilling at $-100^{\circ}C$ caused the more refinement of powder particle size, and enhanced the solubility of Cu or Pb in W, compared with milling at room temperature. In W-12.8wt%Cu-7.2%Pb powder cryomilled at $-100^{\circ}C$, the monotectic temperature of Cu-Pb as well as the melting temperature of Cu was decreased by refinement of Cu crystalline size, and the most amorphization was occurred after milling for 150 h.

• 대한환경공학회지
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• 제30권4호
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• pp.446-452
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• 2008

중금속 제거를 위한 조류 Spirulina platensis의 생물흡착 특성에 관해 연구하기 위하여, 조류 균체와 Ca-alginate를 이용하여 조류를 고정화한 고정체에 대하여 각각 회분식반응기에서 Pb와 Cu의 제거 실험을 하였다. Spirulina platensis 균체에 의한 Pb와 Cu의 생물흡착은 20분 이내에 흡착평형에 도달하였다. Pb와 Cu의 흡착량은 초기 농도가 증가하거나 용액의 pH가 높아짐에 따라 증가하여, pH 4.5$\sim$5.0에서 최적 조건을 나타내었다. Pb 혹은 Cu의 농도가 200 mg/L일 때, Spirulina platensis의 단위 무게당 흡착된 Pb와 Cu의 최대 흡착량은 각각 86.43과 57.02 mg/g이었으며, 이는 같은 조건에서 활성탄보다 1.94와 1.48배 높은 값이다. Spirulina platensis 균체에 의한 Pb와 Cu의 흡착특성은 Freundlich와 Langmuir 흡착등온식에 의해 잘 해석되었으며, Langmuir 흡착등온식에 의해 구한 흡착제 단위 무게당 흡착되는 Pb 혹은 Cu의 최대 흡착량($q_{max}$)은 각각 95.24와 62.50 mg/g이었다. Sp. platensis 균체에 대한 FT-IR 분석결과 여러 가지의 기능기들을 확인하였고, 이러한 기능기들이 수용액상에서 금속 이온과 반응할 수 있다. 조류 Spirulina platensis를 Ca-alginate를 이용하여 고정화한 고정체에 의한 Pb와 Cu의 생물흡착의 경우, 40분 정도에 흡착평형에 도달하여 균체에 의한 경우에 비하여 약간의 확산제한이 관찰되었다.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2004년도 SMICS 2004 International Symposium on Maritime and Communication Sciences
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• pp.57-59
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• 2004

The melting temperature and critical temperature (Tc) of YBa$_2$Cu$_3$Ox with deferent content impurities of PbO and BaPbO$_3$ were studied. When the PbO was used as addition in YBa$_2$Cu$_3$Ox, although the melting point could be reduced, the superconductivity (the transition wide, ΔTc) became poor. From the XRD pattern of the sintered mixture of YBa$_2$Cu$_3$Ox and PbO it was known that there is a reaction between YBa$_2$Cu$_3$Ox and PbO, and the product is BaPbO$_3$. In the process of the reaction the superconducting phase of YBa$_2$Cu$_3$Ox was decreased and in the sample BaPbO$_3$became the main phase. Therefore the superconductivity was reduced. BaPbO$_3$was chosen as the impurity for the comparative study. The single phase BaPbO$_3$was synthesized by the simple way from both mixtures of BaPbO$_3$and PbO, BaPbO$_3$and PbO$_2$. Deferent contents of BaPbO$_3$(10%, 20%, 30%) were added in the YBa$_2$Cu$_3$Ox. By the phase analysis in the XRD patterns it was proved that there were not reactions between YBa$_2$Cu$_3$Ox and BaPbO$_3$. When BaPbO$_3$was used as impurity in YBa$_2$Cu$_3$Ox the superconductivity was much better than PbO as impurity in YBa$_2$Cu$_3$Ox But the melting point of YBa$_2$Cu$_3$Ox with BaPbO$_3$could not be found when the temperature was lower than 1000 $^{\circ}C$ in the DTA measurement.

• 동굴
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• 제78호
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• pp.17-22
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• 2007

The melting temperature and critical temperature (Tc) of $YBa_2Cu_3O_x$ with deferent content impurities of PbO and $BaPbO_3$ were studied. When the PbO was used as addition in $YBa_2Cu_3O_x$, although the melting point could be reduced, the superconductivity (the transition wide, ${\Delta}T_c$) became poor. From the XRD pattern of the sintered mixture of $YBa_2Cu_3O_x$ and PbO it was known that there is a reaction between $YBa_2Cu_3O_x$ and PbO, and the product is $BaPbO_3$. In the process of the reaction the superconducting phase of $YBa_2Cu_3O_x$ was decreased and in the sample $BaPbO_3$ became the main phase. Therefore the superconductivity was reduced. $BaPbO_3$ was chosen as the impurity for the comparative study. The single phase $BaPbO_3$ was synthesized by the simple way from both mixtures of $BaCO_3$ and PbO, $BaCO_3$ and $PbO_2$. Deferent contents of $BaPbO_3$ (10%, 20%, 30%) were added in the $YBa_2Cu_3O_x$. By the phase analysis in the XRD patterns it was proved that there were not reactions between $YBa_2Cu_3O_x$ and $BaPbO_3$. When $BaPbO_3$ was used as impurity in $YBa_2Cu_3O_x$ the superconductivity was much better than PbO as impurity in $YBa_2Cu_3O_x$. But the melting point of $YBa_2Cu_3O_x$ with $BaPbO_3$ could not be found when the temperature was lower than $1000^{\circ}C$ in the DTA measurement.

• 센서학회지
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• 제7권1호
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• pp.67-72
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• 1998

Plused ArF excimer laser ablation과 열증착법에 의해 p형 Si 기판위에 PbTe/CuPc 박막을 증착하였다. 성장된 박막의 구조적, 전기적 특성은 XRD, 전류-전압 곡선등의 분석으로 행하였다. XRD 분석으로부터 PbTe박막과 CuPc 박막은 a 축의 배향성을 지닌 박막으로 성장하였음을 알 수 있었다. PbTe/CuPc/Si 박막의 광전특공을 조사하기 위하여 빛을 조사했을 때와 빛을 조사하지 않았을 때의 수직방향의 전류-전압 (I-V) 특성을 CuPc/Si, PbTe/Si 단층막의 특성과 비교 관찰하였다. PbTe/CuPc/Si 박막에서 단축 광전류 ($J_{sc}$)가 $25.46\;mA/cm^{2}$, 개회로 광전압 ($V_{oc}$)이 170 mV인 커다란 광기전력 특성을 나타내었다. 또한 양자효율 (QE)은 15 %, 광전변환효율 (${\eta}$)은 $3.46{\times}10^{-2}$로 측정되었다. QE와 ${\eta}$를 기초로 한 PbTe/CuPc/Si 접합과 광전류 과정은 CuPc 층에서의 광캐리어 생성, PbTe/CuPc 계면에 의 광캐리어 분리 그리고 PbTe층에서의 광캐리어 운송 역할이 효율적으로 수행된 결과임을 알 수 있었다.