• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2005년도 추계학술대회 논문집 Vol.18
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• pp.202-203
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• 2005

To recognize whether admixture affects some $(Ba_{0.6}Sr_{0.4})TiO_3$, powder in this research $Li_2CO_3$, MgO, $MnO_2$ adding each 3 wt % by Tape casting method thick film make. Sitering temperature lowered 1300$^{\circ}C$ adding $Li_2CO_3$, and density is 5.942g/$cm^3$, and specific inductive capacity increases about decuple and displayed 4000. Climbed sitering temperature 1400$^{\circ}C$ adding MgO, specific inductive capacity reduced 1/2 times. Lowered sintering temperature 1325$^{\circ}C$ low adding $MnO_2$.

• 대한전기학회논문지
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• 제41권6호
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• pp.652-660
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• 1992

0.10Pb(SbS11/2TSnS11/2T)OS13T-0.25PbTiOS13T-0.65PbZrOS13T ceramics modified by LaS12TOS13T(1[mol%]) and MnOS12T(0-0.30[mol%]) were fabricated. The structural and pyroelectric properties with contents of MnOS12T were studied. Crystal structure of a specimen was rhombohedral type and average grain sizes were decreased with increasing the contents of MnOS12T. Relative dielectric constant and dielectric loss factor were minimum in the specimens doped 0.24[mol%]MnOS12T. (PbS10.99TLaS10.01T)[(SbS11/2TSnS11/2T) TiS10.25TZrS10.65T]OS13T specimen modified 0.24[mol%]MnOS12T showed the good pyroelectric properties and pyroelectric coefficient and voltage responsivity were 6.73x10S0-8T[C/cmS02TK], 125[V/W], respectively. Voltage responsivity was increased with decreasing the chopper frequency.

• 대한토목학회논문집
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• 제26권3B호
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• pp.321-327
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• 2006

본 연구는 축산폐수처리를 위해 광촉매의 적용가능성과 처리효율 및 범위를 실험하여 축산폐수처리에 대한 기초 자료로 제시하고자 한다. 축산폐수처리에 대한 광촉매양의 증가는 높은 처리효율을 나타냈으며 알카리 영역에서 보다 산성영역 특히 pH3에서 축산폐수처리 효과는 우수하게 나타났다. 또한 광촉매양의 증가에 따라 색도 보다는 $TCOD_{Mn}$의 제거가 빠르게 이루어 졌다. UV 또는 $TiO_2$를 단독으로 사용하여 폐수처리를 하였을 때 보다 $UV/TiO_2$를 함께 적용하였을 때가 처리효율은 우수하게 나타났으며 산화제로 과산화수소를 주입하였을 때 처리효율은 $UV/TiO_2$만을 적용하였을 때 보다 처리효율이 우수하게 나타났다. 본 실험에서의 과산화수소 적정 주입량은 200 mg/L이며 과산화수소 적정주입량이 보다 많이 주입되었을 때는 처리효율이 떨어지는 것으로 나타났다. 또한 과산화수소의 주입량은 실험 시 계속적으로 주입이 되어야 높은 처리효율을 얻을 수 있었다.

• 전자공학회논문지A
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• 제31A권9호
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• pp.121-127
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• 1994

The capability for application of rf magnetron sputterred and post annealed BaTiO$_{3}$ thin films in dielectrics AC drived TFELD(thin film electroluminescent device) was investigated. The dielectric constant of the thin films slightly increased up to about 25 with increase fothe post annealing temperature in the range of 210$^{\circ}C$-480$^{\circ}C$. The dielectric loss was about 0.005-0.01 except for the high frequency range above 100kHz and nearly independent on post annealing temperature. The BaTiO$_{3}$ thin film used for TFELD was annealed at 480.deg. C and Si$_{3}$N$_{4}$ thin film was inserted between BaTiO$_{3}$, lower dielecrics and ZnS:Mn, phosphor layer for stable driving of the device and for fear of interdiffusion. Regardless of the frequency of the applied sine wave voltage, the threshold voltage of the prepared TFELD was 65volt and saturated brightness was about 3000cd/m$^{2}$ at 130volt(2kHz sine wave), 65volt above V$_{TH}$.

• 한국세라믹학회지
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• 제25권4호
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• pp.321-328
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• 1988

The sintering phenomena, electrical resistivity, dielectric and piezoelectric properties of lead titanate ceramics modified by the partial substitution of La for Pb and Mn for Ti, (Pb1-1.5xLax)(Ti1-yMny)O3 ceramics, have been investigated. In (Pb1-1.5xLax)(Ti1-yMny)O3 system, with increasing lanthanum content, the realtive bulk density increased, but the Curie point and tetragonality (c/a) decreased. The tetragonal-to-cubic phase transition boundary existed in the range of 0.20

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2003년도 International Meeting on Information Display
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• pp.840-844
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• 2003

The main objective of this investigation is to improve the photoluminescent of $Zn_{2}SiO_{4}:Mn$ phosphors prepared by the sol-gel technique. We try to use adding a new co-dopan such as Cr and Ti. The calcination temperature of sol-gel technique(1100 $^{\circ}C$) was lower than that of the solid state reaction (1300 $^{\circ}C$). Under 147nm excitation, the maximum emission intensity was obtained when the concentration of Cr and Ti was 0.1mol% with respect to $Zn_{2}SiO_{4}:Mn$. In order to study the effect of co-dopant, the content of Mn and the ratio of water to TEOS were fixed at 2mol% and 36:1, respectively.

• 한국전기전자재료학회논문지
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• 제20권2호
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• pp.124-129
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• 2007

Dielectric and piezoelectric properties of $0.57Pb(Sc_{1/2}Nb_{1/2})O_{3}-0.43PbTiO_{3}$, which is the morphotropic phase boundary composition for the PSN-PT system, were investigated as a function of $Fe_{2}O_{3},\;Nb_{2}O_{5}\;and\;MnO_{2}$ addition 0 wt% to 0.9 wt%. The maximum dielectric constant of ${\varepsilon}_{33}/{\varepsilon}_{o}=2054$ and the minimum dielectric loss of $tan{\delta}=0.37\;%$ at room temperature were obtained at 0.1 wt% of $Fe_{2}O_{3}$ and 0.5 wt% of $MnO_{2}$ addition, respectively. With addition of 0.5 wt% $Nb_{2}O_{5}$ and $0.5\;wt%\;MnO_{2}$, the electromechanical coupling factor $k_{p}$ and mecanical quality factor $Q_{m}$ were significantly increased, respectively. The maximum electromechanical coupling factor $k_{p}=61.5\;%$ was obtained by addition of $Nb_{2}O_{5}$ and high mechanical quality factor $Q_{m}=919$ was obtained by addition of $MnO_{2}$. The $Q_{m}(=919)$ value is 3.3 times larger than that of non-doped 0.57PSN-0.43PT ceramics.

• 한국세라믹학회지
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• 제28권2호
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• pp.101-108
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• 1991

0.2 mo1% La doped BaTiO3 samples were prepared by a wet chemical process (Pechini process) and electrical conductivity were measured from annealing temperatures(800-110$0^{\circ}C$) to room temperature continuously. 2 probe I-V characteristics showed that Pt electrodes were non-ohmic below about 80$0^{\circ}C$ for Ladoped sample. I-V curves showed varistor behavior and breakdown voltages showed PTC-like behavior. AC complex impedance of 0.2 La and 0.05 Mn mo1% doped BaTiO3 samples with three different electrodes (electroless Ni, Pt, Ag electrodes) were measured with temperature variation. Complex impedance plots showed that the samples with electroless Ni electrodes have negligible electrode resistance. Samples with Ag or Pt paste electrodes showed large electrode resistance. PTC effect, which is defined as the ratio of maximum resistance to minimum resistance, was found to be less than 10 for 0.2 mo1% La doped dense sample however greater than 105 with codoping of 0.05 mo1% Mn and 0.2 mol% La.

• 한국재료학회지
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• 제2권4호
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• pp.263-269
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• 1992

본 실험에서는 낮은 음의 온도계수를 갖는 저온 소결 유전체에 대해 연구하였다. 새로 개발된 재료의 조성은 Ti$O_2$(100-X) CuOx(X=1~5wt%)에 미량의 Mn$O_2$를 첨가 하였다. CuO를 첨가하지 않은 경우에는 저온 (90$0^{\circ}C$) 에서 소결이 진행되지 않았다. CuO 함량이 증가할수록 저온에서 소결이 가능하였으나, 유전율이 낮아지고 유전손실은 증가 하였다. Mn$O_2$를 0.6wt% 첨가한 경우 유전율과 Q값이 가장 높게 나타났다.

• 한국세라믹학회지
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• 제37권4호
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• pp.395-401
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• 2000

In this study, we chose the basic composition which indicated the best electrical properties by change of x content(0, 0.05, 0.1, 0.15, 0.2, 0.25 mol respectively) in xPb(Mn1/3Sb2/3)O3-(1-x)Pb(Zr0.52Ti0.48)O3 ceramics. And we substituted Cd2+ for Pb2+ site, then observed the sintering behavior, microstructure and electrical propertties according to the various sintering temperature. The basic composition was the 0.05PMS-0.95PZt, and it showed single perovskite phase and excellent properties. In case of Cd2+ substitution, we were able to sinter at 90$0^{\circ}C$ which was lower than conventional sintering temperature(1200~130$0^{\circ}C$). Especially, when the 2mol% substituted PMS-PZT specimens were sintered at 90$0^{\circ}C$ for 2h, we obtained the p=7.6g/㎤, kp=56%, Qm=520 and made sure of a position of Cd2+ substitution by observing lattice parameter, phase transition temperature. From this results, we could infer that because Cd2+ substituted fro A-site, low temperature sintering of Cd2+ substituted PMS-PZT without any loss of electrical properties shows its applicability for the piezoelectric ceramic transformer.