• 제목/요약/키워드: Pb content

검색결과 831건 처리시간 0.034초

시판 웅담의 미량금속 정량에 관한 연구 (Determination of Trace Metals in Fel Ursi)

  • 이숙연;유봉신;문혜령;김성경
    • 생약학회지
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    • 제13권3호
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    • pp.102-105
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    • 1982
  • Nine trace elements in Bear Galls(Fel Ursi) studied in this paper are Na, Mg, K, Ca, Cu, Zn, Fe, Pb and Ge. The contents of Na, Mg, K, Ca, Cu, Zn, Fe, Pb are determined by atomic absorption spectrometry and Ge is determined by graphite atomic absorption spectrometry. In both methods, the sample is digested with nitric-perchloric acid and then ashed. The results of analysis are shown in table and the result obtained from this study are as follows. a. The highest content of trace element of Bear Gall is Na and other elements are getting lower in order of K, Mg, Ca, Ge, Zn, Fe, Cu, and Pb. b. Particularly the content of Ge in Bear Gall was determined.

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MnO2가 첨가된 PSN-PNN-PT 세라믹스의 유전 및 압전특성 (Dielectric and Piezoelectric Properties of MnO2-doped PSN-PNN-PT Ceramics)

  • 이종덕
    • 센서학회지
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    • 제13권2호
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    • pp.152-156
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    • 2004
  • The dielectric and piezoelectric properties of 0.36Pb($Sc_{1/2}Nb_{1/2}$)$O_{3}$-0.25Pb($Ni_{1/3}Nb_{2/3}$)$O_{3}$-0.39Pb$TiO_{3}$ (hereafter PSNNT) at the morphotropic phase boundary (MPB) composition were investigated with $0{\sim}2.5$ mot% $MnO_{2}$ doping. Bulk density, dielectric loss and tetragonality of crystal structure were all improved with increasing $MnO_{2}$ additive content. With increasing $MnO_{2}$ additive content, the electromechanical coupling factor and quality factor were also increased: Electromechanical coupling $k_{p}$ and quality factor $Q_{m}$ at 2.0 mol% $MnO_{2}$ doping with were showed highest values of 55.6 % and 252, respectively.

Sol-Gel 법에 의한 (Pb, La)TiO$_3$ 박막의 전기적 특성 (Electrical Properties of (Pb, LaITiO$_3$ Thin Films fabricated by Sol-Gel Processing)

  • 구본혁;박정흠;장낙원;마석범;박창엽
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 1997년도 추계학술대회 논문집
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    • pp.48-51
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    • 1997
  • (Pb. La)TiO$_3$ thin films were fabricated by sol-gel Processing and spin-coated on the Pt substrate. The spin-coated PLT films were sintered at 75$0^{\circ}C$ for 5min by rapid thermal ann La content dependence of the electrical properties of the PLT thin films are discussed. Wit La mole% from 20 to 36mo1e%. the dielectric constant of the PLT thin films decreased f 570. P-E hysteresis loops changed from ferroelectric to paraelectric. and the charge storage charging time decreased. The Curie Point decreased with increasing La content. The leak density also decreased and La 36mo1% species shows mood characteristics less than 10- electric field 500 (KV/cm) Because of the broad range of composition-controlled ferroelectric PLT thin films are suitable for memory application.

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Characterization of $BaO-B_2O_3-SiO_2$ glass for the application to PDP;Effect of BaO/$B_2O_3$ ratio

  • Lim, Eun-Sub;Kim, Byung-Sook;Lee, Joon-Hyung;Kim, Jeong-Joo
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2004년도 Asia Display / IMID 04
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    • pp.1099-1102
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    • 2004
  • For the development of Pb-free low temperature sintering glass frits, $BaO-B_2O_3-SiO_2$ system was examined. The content of BaO and $B_2O_3$ was changed when the content of $SiO_2$ was fixed to 10 mol%. When the content of BaO was more than 60 mol% devitrification was observed. In the sintering temperature range between 520${\sim}$620 $^{\circ}C$, the optimum sintering temperature decreased as the content of BaO increased. When BaO ${\geq}$45 mol%, the glasses were crystallized after sintering. Candidate compositions are suggested in $BaO-B_2O_3-SiO_2$ system, which can replace the PbO containing glass system.

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낮은 최고전류밀도 조건에서 파형전류전해에 의한 Pb-Sn합금 전착층의 조성 및 조작특성 (Composition and microstructure of Pb-Sn alloy electrodeposits in pulse plating with low peak current density)

  • 예길촌;백민석
    • 한국표면공학회지
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    • 제24권2호
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    • pp.88-95
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    • 1991
  • The tin-lead alloy was electrodeposited in the low range of peak current density in order to investigate the change of composition and microstructure of them. The Pb content of alloy deposits, which was decreased with increasing average current density, was relatively lower than that of D.C. plated alloy deposit. The preferred orientation of alloy deposit was changed with increasing peak current density and the surface morphology of alloy deposits was closely related to the preferred orientation of them.

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Pb 중독에 Fe, Cu가 흰쥐의 체내에 미치는 효과에 관한 연구 (The Effect of Fe and Cu on the Pb Toxicity in Rats)

  • 김애정
    • 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.

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Effects of Additives on the Properties of $YBa_2Cu_3O_x$

  • Soh, Dea-Wha;Cho, Yong-Joon;Fan, Zhanguo
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2004년도 추계학술대회 논문집 Vol.17
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    • pp.341-344
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    • 2004
  • The superconducting properties of $YBa_2Cu_3O_x$ with different content impurities of PbO and $BaPbO_3$ were studied. When the PbO was used as an additive in $YBa_2Cu_3O_x$, although the melting point could be reduced, the superconductivity 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 $BaPbO_3$ would be the main phase in the sample. Therefore, $BaPbO_3$ was chosen as the impurity additive for the comparative study. The single phase of $BaPbO_3$ was synthesized by the simple way from both mixtures of $BaCO_3$ and PbO, $BaCO_3$ and $PbO_2$. Different 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 was no reaction 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 an impurity additive in $YBa_2Cu_3O_x$.

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$Fe_2O_3$ 첨가에 따른 $Pb(Y_{1/2}Ta_{1/2})O_3-PbZrO_3-PbTiO_3$ 세라믹스의 전기적 특성 (Electrical Properties of $Pb(Y_{1/2}Ta_{1/2})O_3-PbZrO_3-PbTiO_3$ Ceramic s as a function of $Fe_2O_3$content)

  • 강도원;김태열;김범진;박태곤;김명호
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 1999년도 추계학술대회 논문집
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    • pp.297-299
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    • 1999
  • Effects of additives on the ceramic and electrical properties of Pb(Y$_{1}$2/Ta$_{1}$2/)O$_3$-PbZrO$_3$-PbTiO$_3$ceramics in a perovskite type structure were investigated. The dielectric and piezoelectric properties of the base composition were improved markedly through selection of Fe$_2$O$_3$ additives in proper amounts. The composition Pb(Y$_{1}$2/Ta$_{1}$2/)O$_3$-PbZrO$_3$-PbTiO$_3$ obtained the dielectric constant ($\varepsilon$$_{r}$=1,425). Also, electromechanical couping factors for planar(k$_{p}$) and piezoelectric constant(d$_{33}$) were obtained 0.50 and 294[pC/N] at the additives 0wt% Fe$_2$O$_3$ respectively. The mechanical quality facor(Q$_{m}$) of Pb(Y$_{1}$2/Ta$_{1}$2/)O$_3$-PbZrO$_3$-PbTiO$_3$+Fe$_2$O$_3$(0.3 wt%) is about 510.510.510.

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