• 제목/요약/키워드: Zn content

검색결과 1,309건 처리시간 0.025초

종결정법을 이용한 저전압 ZnO 배리스터의 제조 및 전기적 특성 (Preparation of Low Voltage ZnO Varistor Using Seed Grain Method and Its Electrical Properties)

  • 강승구;오재희
    • 한국세라믹학회지
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    • 제25권5호
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    • pp.552-560
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    • 1988
  • ZnO low voltage varistor was obtained by varying a) the amount of seed grains, b) the size of seed grains, and c) sintering temperature. Also, the optimum condition for fabricating the ZnO seed grains was studied. Large ZnO seed grains were obtained by washing a ZnO sintered body containing 1m/of BaCO3 in boiling water. When the seed grains were added, abnormal grain growth occurred, and the varistor voltage sharply decreased. However, when more than 5w/o of seed grain content was added, the varistor voltage gradually increased. When 10w/o seed grains of 75~106${\mu}{\textrm}{m}$ were added and sintered for 2 hours at 1200 to 125$0^{\circ}C$, low voltage varistor properties with V1mA/mm of 19V/mm and nonlinear exponent ($\alpha$) of 12 occurred.

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A Study on ZnSSe : Te/ZnMgSSe DH Structure Blue and Green Light Emitting Diodes

  • Lee Hong-Chan
    • Journal of Advanced Marine Engineering and Technology
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    • 제29권7호
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    • pp.795-800
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    • 2005
  • The optical properties of $ZnS_{y}Se_{1-x-y}:Te_x\;(x\;<\;0.08,\;y\∼0.11$) alloys grown by molecular beam epitaxy (MBE) have been investigated by photoluminescence (PL) and PL-excitation (PLE) spectroscopy. Good optical properties and high crystal quality were established with lattice match condition to GaAs substrate. At room temperature, emission in the visible spectrum region from blue to green was obtained by varying the Te content of the ZnSSe:Te alloy. The efficient blue and green emission were assigned to $Te_{1}$Tel and $Te_{n}$ (n$\geq$2) cluster bound excitons, respectively. Bright blue (462 nm) and green (535 nm) light emitting diodes (LEDs) have been developed using ZnSSe:Te system as an active layer.

Inactivation of Copper, Zinc Superoxide Dismutase by the Lipid Peroxidation Products Malondialdehyde and 4-Hydroxynonenal

  • Koh, Young-Ho;Yoon, Seon-Joo;Park, Jeen-Woo
    • BMB Reports
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    • 제32권5호
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    • pp.440-444
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    • 1999
  • Membrane lipid peroxidation processes yield reactive aldehydes that may react with copper,zinc superoxide dismutase (Cu,Zn SOD), one of the key antioxidant enzymes against oxidative stress. We investigated this possibility and found that exposing Cu,Zn SOD to malondialdehyde (MDA) or 4-hydroxynonenal (HNE) caused the loss of dismutase activity, cross-linking of peptides, and an increase in protein oxidation, reflected by the increased level of carbonyl groups. When Cu,Zn SOD that had been exposed to MDA or HNE was subsequently analyzed by amino acid analysis, histidine content was found to be significantly lost. Both MDA-and HNE-treated Cu,Zn SOD were resistant to proteolysis, which may imply that damaged proteins exist in vivo for a longer period of time than the native enzyme. The lipid peroxidation-mediated damage to Cu,Zn SOD may result in the perturbation of cellular antioxidant defense mechanisms, and subsequently lead to a pro-oxidant condition.

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조성비에 따른 Pb($Zn_{x}Nb_{1-x}$)$O_3$세라믹의 전기적 특성 (Electrical Properties of Pb($Zn_{x}Nb_{1-x}$)$O_3$ Ceramic by Composition)

  • 이수호;사공건
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 1993년도 추계학술대회 논문집
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    • pp.14-16
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    • 1993
  • In this Paper. Pb($Zn_{x}Nb_{1-x}$)$O_3$ ceramics were fabricated by the mixed oxide method. The sintering temperature and time were 1,000($^{\circ}C$). 1(hr). respectively. According to the contents of $ZnO_2$, the depression of pyrochlore phase and its effects were studied. As the results of the XRD patterns and SEM. the pyrochlore and second phase were increased with increasing the $ZnO_2$. As the $ZnO_2$ content was increased. density was decreased.

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ZnO-SnO$_2$복합체의 일산화탄소 가스감응 특성 (CO Gas Response Characteristic of ZnO-SnO$_2$Composite)

  • 김태원;최우성;정승우
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 1997년도 춘계학술대회 논문집
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    • pp.41-44
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    • 1997
  • Using the 2 probe mothods, AC coductivities, dielectric loss factors, capacitances, and impedances were investigated to study. The electrical and sensing properties for SnO$_2$ added ZnO. In air The electrical conductivity of SnO$_2$added ZnO decrease by increasing the content of SnO$_2$, and the relative dielectric constants for 0.05, 5, 7 SnO$_2$ added ZnO are 55, 20, 14, respectively. In 3000ppm CO Gas. relative dielectric constants for 3, 5mol% SnO$_2$ added ZnO are 163, 68, respectively.

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ZnO-TiO$_2$ 복합체의 전기적 성질과 일산화탄소 감응특성 (CO Gas Response Characteristic and Electrical Properties of ZnO-TiO$_2$Composite)

  • 김태원;최우성;박춘배;정승우;소병문;백승철
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 1997년도 춘계학술대회 논문집
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    • pp.103-106
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    • 1997
  • The electrical properties and the sensing properties of ZnO-TiO$_2$ composites were investigated by using the complex impedance measurement and voltage-current source and measurement unit. In air, the electrical conductivity of TiO$_2$ added ZnO increase with increasing the content of TiO$_2$ and the relative dielectric constants for 3, 5 and 7mol% TiO$_2$ added ZnO are 7, 13 and 120, respectively. In 3000ppm CO gas, the relative dielectric constants for 3, 5mol% TiO$_2$ added ZnO are 25, 28, respectively.

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Red-shift of the photoluminescence peak of N-doped ZnO phosphors

  • Kim, Jun-Kwan;Lim, Jung-Wook;Kim, Hyun-Tak;Yun, Sun-Jin
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2008년도 International Meeting on Information Display
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    • pp.895-897
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    • 2008
  • ZnO films were fabricated using rf-magnetron sputter deposition process with different $N_2$ ambient. N-content in N-doped ZnO films was less than 1%. The wavelength of the highest intensity PL peak of N-doped ZnO was shifted to higher wavelength with increasing $N_2$ flow rate in the deposition ambient. These results indicated that the optical property of ZnO was significantly affected by the defect level created by doping with a very small amount of N.

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Pb($Zn_{1/3}Nb_{2/3})O_3-Ba(Zn_{1/3}Nb_{2/3})O_3-PbTiO_3$ 세라믹의 압전특성에 관한 연구 (A Study on the Piezoelectric Properties of the Pb($Zn_{1/3}Nb_{2/3})O_3-Ba(Zn_{1/3}Nb_{2/3})O_3-PbTiO_3$)

  • 박혜옥;박인길;이성갑;이영희
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 1989년도 춘계학술대회 논문집
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    • pp.70-73
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    • 1989
  • (1-x-y)Pb($Zn_{1/3}Nb_{2/3})O_3-Ba(Zn_{1/3}Nb_{2/3})O_3-PbTiO_3(0.12{\leq}x{\leq}0.21, 0.24{\leq}y{\leq}0.33$) ternary compound ceramics were fabricated by the mixed oxide method. The sintering temperature and time were 1050 [$^{\circ}C$], 2[hr]. Morphotropic phase boundary region was chosen for the composition. 0.55 PZN-0.21 BZN-0.24 PT specimen had the highest value of relative dielectric constants, 5353. The curie temperature of specimens were increased linearly with PT content. Near the morphotropic phase boundary, electro-mechanical coupoling factor and mechanical quality factor of the specimens had the highest values.

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부산지역 토양중의 Cu, Pb, Zn, Cd, Mn의 지구화학적 분산 (Geochemical Dispersion of Cu, Pb, Zn, Cd and Mn in Soils from the Pusan Area)

  • 김진섭;박맹언;윤일
    • 자원환경지질
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    • 제30권2호
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    • pp.117-122
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    • 1997
  • Soils collected from pusan metropolitan city were analysed for Cu, Pb, Zn, Cd, Mn to determine their dispersion patterns, mode of occurrences and to investigate the pollution level of heavy metals by urbanization. Element couples of Zn-Cu and Pb-Cd showed good correlation respectively and pollution sources of Zn-Cu, and Pb-Cd were similar. Pb was highly enhanced in dense traffic areas. Soil chemistry around mineralized areas originating from basic host rocks are characterized by high content of Pb, Zn, Cu, Cd, Mn and As.

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Self-Illuminated Smart Window Based on Polymer-Dispersed Liquid Crystal Mixed with Cu-doped ZnS

  • Kim, Eun Mi;Heo, Gi-Seok
    • 한국전기전자재료학회논문지
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    • 제35권6호
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    • pp.562-567
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    • 2022
  • Novel self-illuminated smart windows were fabricated consisting of Cu-doped ZnS (ZnS:Cu) powder and polymer-dispersed liquid crystal (PDLC). This smart window shows not only switchable transparency but also self-illumination without any attachable luminous body. Its electro-optical characteristics, transmittance, and luminance were investigated in relation to various applied voltages and composition ratios. The optical transmittance and luminous intensity increased with increasing applied voltages. However, the optical transmittance decreased with increasing ZnS:Cu powder content. One of the self-illuminated smart windows, which was fabricated with 9 wt% of ZnS:Cu, achieved the optical transmittance of 60.5% (at 550 nm) and the luminance of 11.0 cd/m2 at 100 V. This smart window could be used as a normal switchable smart window in daytime and light-emitting signage at night.