• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1999년도 추계학술대회 논문집
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• pp.294-296
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• 1999

Solid solution ceramics having various ratios between xPb( $Y_{1}$2/T $a_{1}$2/) $O_3$ and Pb(Z $r_{0.52}$ $Ti_{0.48}$) $O_3$were synthesized by a conventional solid state reaction for well sintered specimens, dielectric and piezoelectric prperties were studied as a function of composition. The dielectric constant of PYT-PZT ceramics of 4 mol% PYT was 1,424 at room temperature. The maximum value of electromechanical couping facotr $k_{p}$ of 51% $k_{t}$ of 30% were obtained at the composition of 4 mol% PYT, howerver mechanical quality factor( $Q_{m}$) had a minimum value of 69 at 4 mol% PYT. Also the maximum value of piezoelectric constant of $D_{33}$(310[pC/N]) and $d_{31}$(-131[pC/N]) were obtained at the composition of 4 mol% PYT content.ntent.t.t.t.

• 공업화학
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• 제29권5호
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• pp.549-555
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• 2018

본 연구에서는 울트라 배터리의 전기화학적 성능을 향상시키기 위해서 Nano-Pb/Activated Carbon (Nano-Pb/AC) 복합소재와 전해액 첨가제의 특성이 조사되었다. 제조된 복합 소재의 물리적 특성은 FE-SEM, TEM, XPS, BET를 이용하여 분석하였고, 울트라 배터리의 전기화학적 성능은 사이클, 율속, 임피던스 테스트를 통해 조사되었다. 납 산 배터리에 비하여 나노 납 함량이 9 wt%인 복합소재로 코팅된 울트라 배터리는 사이클 성능이 150%로 개선되었으며, 1-5 C 율속 테스트에서 방전 용량이 119-122%로 증가되었다. 또한 임피던스 테스트 결과 나노 납 함량이 증가할수록 내부 저항의 크기가 작아지는 것을 확인하였다. 전해액 첨가제가 0.45 vol% 포함된 배터리의 장기 사이클 성능은 140%로 향상되었다.

• Journal of Nutrition and Health
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• 제30권9호
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• pp.1045-1049
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• 1997

In order to study the content of selected elements in the organs of the mice, mice were fed with green juice of Angelica keiskei Koidz for 16 weeks. The results obtained from the experiments are summarized as follows : 1) The element contents(cr, Mn, Ni, Cu, Zn, Cd, Ba, Pb, and Fe) in the whole plant are generally the same as those the previous reports. 2) The element contents(Cr , Mn, Ni, Cu, Zn, Cd, Ba, Pb and Fe) in the green juice did not exceed those of the edible water standard. 3) The element contents (Cr, Mn, Ni, Cu, Zn, Cd, Ba, Pb and Fe) in the brain is slightly higher than those in the whole plants. 4) The element contents(Cr, Ni, Pb and Fe) in the organs of the mice fed green juice for 16 weeks are the same as those of the previous reports.

• 한국응용과학기술학회지
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• 제25권4호
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• pp.518-524
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• 2008

In this study, positive plates of lead acid battery of Pb-Ca alloy and Pb-Ca-Sn alloy were fabricated and the mechanical characteristics of positive plates were measured. This study observed how the changes of content of Ca & Sn affect interface corrosion which is located in between grid & active materials and lead acid batteries as well. The mechanical characteristics of grid alloy is better when Ca is 0.05 wt.% then 0.1 wt.%. This study said that the corrosion rate between the active material based on the charge/discharge cycle of lead acid battery and grid interface is much faster than a grid which contains Sn. And furthermore, according to the study the rate 30 of Sn/Ca which is added to grid shows the best performance.

• Toxicological Research
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• 제17권4호
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• pp.309-316
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• 2001

Male Sprague Dawley rats were exposed to 0, 0.04, 0.2, and 0.8% Pb acetate in drinking water for 13 weeks and fed a commercial diet. Dose-related adverse effects observed at the end of the Pb acetate exposure in the drinking water were as follows: decrease in body weight gain, decrease in hemoglobin, hematocrit(HCT), mean corpuscular volume (MCV) and mean corpuscular hemoglobin (MCH), increase in serum glucose, decrease in serum testosterone, increase in lead accumulation and $\delta$-ALA release in urine, and decrease in $\delta$-ALAD activities DNA content and histopathlogy (intranuclear inclusion body in kidney proximal tubule cell). Taken together, repeated exposure of lead acetate induced toxicities in hematopoietic system, especially testis and kidney.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1994년도 하계학술대회 논문집 C
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• pp.1466-1468
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• 1994

In this paper Dielectric and strain properties of (1-x-y)PMN-yPT-xST Ceramics have been investigated as a function of the amount of $SrTiO_3(ST)$. The $SrTiO_3$ content is ranged from 0.01-0.06(wt%). As the amount of ST is increased, dielectric constant has a maximum value at 0.05 mol composition. The Curie temperature is decreased linearly with increasing ST composition and Polarization properties have been investigated. Coercive field and ramnant polarization has a maximum value at 0.01mol composition.

• 한국세라믹학회지
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• 제26권2호
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• pp.249-257
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• 1989

Dielectric properties and the stability of the perovskite phase in the Pb(Mg1/3Nb2/3)O3 system have been investigated as a function of amount of BaTiO3 and firing temperature. In the specimens fired at 120$0^{\circ}C$, the pyrochlore phase was eliminated by the addition of 10-15m/o BaTiO3 and also the dielectric constant increased. However, the dielectric constant decreased with further addition of BaTiO3 even though no pyrochlore phase was found to be present. The reducing tendency of the pyrochlore phase decreased with lowering the firing temperature in the system of Pb(Mg1/3Nb2/3)O3 with BaTiO3. Dielectric properties in PMN ceramics were affected by the character of the BaTiO3 rather than the pyrochlore phase.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1994년도 춘계학술대회 논문집
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• pp.5-8
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• 1994

In this paper, Dielectric and strain properties of (1-x-y)PMN-yPT-xST Ceramics hale been investigated as a function of the amount of SrTiO$_3$(ST). The SrTiO$_3$ content is ranged from 0.01-0.05(wt%). As the amount of ST is increased, dielectric constant has a maximun value at 0.05 mol% composition. The Curie temperature is decreased linearly with increasing ST composition and Polarization properties have been investigated. Coercive field and remnant polarization has a maximum value at 0.01mo1% composiion.

• 한국세라믹학회지
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• 제32권11호
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• pp.1269-1275
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• 1995

Effects of GeO2 addition on the thermal and structural stabilities of PbO-Bi2O3-Ga2O3 glasses were studied. Thermal stabilities, as assessed by the weighted thermal stability factors [(Tx-Tg)/Tg], increased with GeO2 concentraton from 0.097 to 0.210 with the addition of 20 mol% GeO2. Increasing GeO2 content resulted in the decrease of apparent density, molar volume, refractive index and thermal expansion. On the other hand, IR transmission cut-off (λT=50%) moved from 6.73${\mu}{\textrm}{m}$ for the ternary PbO-Bi2O3-Ga2O3 glass to shorter wavelength side, 5.98${\mu}{\textrm}{m}$ for a glass containing 20mol% GeO2. There were little change with GeO2 content, however, in the activation energies for the viscous flow of approximately 140 kcal/mole within the temperature interval of 300~50$0^{\circ}C$. Addition of GeO2 to PbO-Bi2O3-Ga2O3 glasses enhanced the thermal and structural stabilities significantly at the expense of their infrared transmittance. An appropriate compsomise between these two opposite trends should be made following the specifications of the final applications.

• 한국식품영양과학회지
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• 제23권1호
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• pp.7-12
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• 1994

철보충이 납종독된 흰쥐의 체내 무기질 함량과 DALAD activity 및 해독에 미치는 영향을 관찰하기 위해, 흰쥐에게 납 2,000ppm을 함유한 식수를 제한없이 주면서, 철분 100ppm, 500ppm을 보충한 식이로 5주동안 사육하여 얻을 결과는 다음과 같다. 체중증가량, 식이섭취량 및 식이효율은 납급여군이 대조군보다 낮게 나타났으며, 철보충납급여군은 납단독급여군보다 높은 것으로 나타났다. 간과 심장의 무게는 차이를 보이지 않았으나, 신장은 납급여군이 대조군보다 증가를 보였다. 비장은 납단독급여군에서만 증가를 보였고, 철보충납급여군에서는 대조군과 차이를 보이지 않았다. 헤마토크릿치는 철보충납급여군에서는 대조군과 차이를 보이지 않았으나, 납단독급여군은 유의적인 감소를 보였다. DALAD activity는 혈액과 간 모두 납급여군에서 대조군보다 유의적인 감소를 보였으나, 납단독급여군보다 철보충납급여군이 높게 나타났고, 철보충수준이 높을수록 높게 나타났다. 혈청과 간의 amino-transferase activity는 철보충납급여군에서는 대조군과 비슷한 경향을 보였으나 납단독급여군에서는 유의적인 증가를 보였다. 혈청 납함량은 납단독급여군과 철보충납급여군 사이에 차이를 보이지 않았으나, 간의 납함량은 철보충납급여군이 납단독급여군보다 높게 나타났다. 혈청 철함량은 납급여군이 대조군보다 감소했으나, 간의 철함량은 납급여군에서 높게 나타났으며, 철보충납급여군이 납단독급여군보다 증가를 보였다. 혈청과 간의 구리함량은 납단독급여군은 대조군과의 차이를 보이지 않았으나, 철보충납급여군은 감소를 보였다.