in order to realize the co-firing with Ag/Pd electrodes in multilayer devices, Pb(Zn1/3Nb2/3)(1-x-y) ZrxTiyO3(0.25<x<0.35, 0.25<y<0.35) piezoelectric ceramics thereafter designated PZN-PZT) modified by La2...in order to realize the co-firing with Ag/Pd electrodes in multilayer devices, Pb(Zn1/3Nb2/3)(1-x-y) ZrxTiyO3(0.25<x<0.35, 0.25<y<0.35) piezoelectric ceramics thereafter designated PZN-PZT) modified by La2O3 has been prepared by conventional technique with sintering temperature from 1100 degreesC to 1140 degreesC. X-ray diffraction patterns demonstrated that pure perovskite phase was obtained. Secondary electron image (SEI) showed that crystalline grains in ceramics were well grown. d(33) of manufactured sample was as high as 560 x 10(-12)C/N. k(p) was about 0.61 and tg delta about 30 x 10(-3). The existence of liquid phase examined by electron diffraction in PZN-PZT sample is beneficial to sintering of the ceramic.展开更多
The phase structure and electrical properties of pure and La2O3-doped Bi-InO3-PbTiO3 (BI-PT) ceramics were studied respectively. In (1 -x)BI-xPT (x=0.72-0.80) ceramics, the stability of tetragonal phase increase...The phase structure and electrical properties of pure and La2O3-doped Bi-InO3-PbTiO3 (BI-PT) ceramics were studied respectively. In (1 -x)BI-xPT (x=0.72-0.80) ceramics, the stability of tetragonal phase increased with increasing x, and pure perovskite structure was obtained for x=-0.80 ceramics. The phase transition temperature range was between 575 ℃ and 600 ℃ for x=0.72-0.80 ceramics, higher than that of PT (-490 ℃). The c/a ratio almost linearly decreased with increasing La2O3 content in x-0.80 ceramics. It is believed that Pb^2+ vacancies were formed by La^3+ substituting Pb^2+ in La2O3-doped BI-PT ceramics. Tc shifted to lower temperature by 30 ℃/mol% La2O3. The maximum dielectric constant 8557 around 559 ℃ was exhibited in 0.5mol%-doped BI-0.80PT ceramics. La2O3-doped ceramics could be poled resulting from decreasing of c/a ratio and improving of dielectric loss and resistivity. The maximum piezoelectric coefficient d33 was 12 pC/N for 2mol%-doped BI-0.80PT ceramics.展开更多
BiFeO3-PbTiO3 (BFO-PT) thin films were prepared on Pt/TiO2/SiO2/Si substrates by pulsed-laser deposition (PLD) technique under different oxygen pressures. The structures of the films were characterized by means of XRD...BiFeO3-PbTiO3 (BFO-PT) thin films were prepared on Pt/TiO2/SiO2/Si substrates by pulsed-laser deposition (PLD) technique under different oxygen pressures. The structures of the films were characterized by means of XRD. The current densities were performed to check the conductivity of the films. The dielectric constant and loss factor (tanδ) of the films were measured. The results show that the BFO-PT layers are mainly perovskite structured; the film deposited under 6.665 Pa exhibits low leakage current, low dielectric loss (0.017-0.041) and saturated hysteresis loop with polarization (Pr) value and coercive field (Ec) of 3 μC/cm2 and 109 kV/cm.展开更多
目的:探究观察3M Single Bond Universal粘接系统对前牙E-max铸瓷贴面修复的远期疗效。方法:选择2017年5月-2019年5月笔者医院收治的需前牙E-max铸瓷贴面修复患者63例(患牙113颗)为研究对象,均行经典贴面修复,根据粘接系统的不同将患者...目的:探究观察3M Single Bond Universal粘接系统对前牙E-max铸瓷贴面修复的远期疗效。方法:选择2017年5月-2019年5月笔者医院收治的需前牙E-max铸瓷贴面修复患者63例(患牙113颗)为研究对象,均行经典贴面修复,根据粘接系统的不同将患者分为观察组(患者21例,患牙40颗,采用3M Single Bond Universal粘接系统)、对照1组(患者21例,患牙36颗,采用VariolinkⅡ粘接系统)、对照2组(患者21例,患牙37颗,采用BISCO CHOICE 2粘接系统)。治疗后三组均于1周、3个月、12个月时进行随访,观察三组治疗后1周、3个月、12个月内贴面修复效果、贴面修复失败率及不良反应发生率。结果:术后1周,三组患者均无失败案例;对照1组存在2颗修复体保存完整度为Ⅰ级的患牙,对照2组存在3颗修复体保存完整度为I级的患牙,观察组未存在该类患者;术后12个月,观察组存在1颗修复体保存完整度Ⅱ级患牙,对照1组存在1颗保存完整度I级患牙,3颗修复体保存完整度Ⅱ级患牙,对照2组存在2颗保存完整度I级患牙,3颗修复体保存完整度Ⅱ级患牙。三组患者治疗效果比较,差异无统计学意义(P>0.05);术后1周、3个月、12个月三组贴面修复失败率比较,差异无统计学意义(P>0.05);随访期间内,三组患者不良反应情况比较差异均无统计学意义(P>0.05)。结论:对于前牙E-max铸瓷贴面修复患者,选取合适的适应证,并做好备牙步骤,3M Single Bond Universal与经典VariolinkⅡ粘接系统及BISCO CHOICE 2粘接系统治疗效果并无显著差异,值得在临床推广使用。展开更多
文摘in order to realize the co-firing with Ag/Pd electrodes in multilayer devices, Pb(Zn1/3Nb2/3)(1-x-y) ZrxTiyO3(0.25<x<0.35, 0.25<y<0.35) piezoelectric ceramics thereafter designated PZN-PZT) modified by La2O3 has been prepared by conventional technique with sintering temperature from 1100 degreesC to 1140 degreesC. X-ray diffraction patterns demonstrated that pure perovskite phase was obtained. Secondary electron image (SEI) showed that crystalline grains in ceramics were well grown. d(33) of manufactured sample was as high as 560 x 10(-12)C/N. k(p) was about 0.61 and tg delta about 30 x 10(-3). The existence of liquid phase examined by electron diffraction in PZN-PZT sample is beneficial to sintering of the ceramic.
文摘The phase structure and electrical properties of pure and La2O3-doped Bi-InO3-PbTiO3 (BI-PT) ceramics were studied respectively. In (1 -x)BI-xPT (x=0.72-0.80) ceramics, the stability of tetragonal phase increased with increasing x, and pure perovskite structure was obtained for x=-0.80 ceramics. The phase transition temperature range was between 575 ℃ and 600 ℃ for x=0.72-0.80 ceramics, higher than that of PT (-490 ℃). The c/a ratio almost linearly decreased with increasing La2O3 content in x-0.80 ceramics. It is believed that Pb^2+ vacancies were formed by La^3+ substituting Pb^2+ in La2O3-doped BI-PT ceramics. Tc shifted to lower temperature by 30 ℃/mol% La2O3. The maximum dielectric constant 8557 around 559 ℃ was exhibited in 0.5mol%-doped BI-0.80PT ceramics. La2O3-doped ceramics could be poled resulting from decreasing of c/a ratio and improving of dielectric loss and resistivity. The maximum piezoelectric coefficient d33 was 12 pC/N for 2mol%-doped BI-0.80PT ceramics.
基金Project(04A1B18) supported by Shanghai Municipal Education Commission Project(50472098) supported by the National Natural Science Foundation of China Project(04qmx1440) supported by Shanghai Rising Star Program, China
文摘BiFeO3-PbTiO3 (BFO-PT) thin films were prepared on Pt/TiO2/SiO2/Si substrates by pulsed-laser deposition (PLD) technique under different oxygen pressures. The structures of the films were characterized by means of XRD. The current densities were performed to check the conductivity of the films. The dielectric constant and loss factor (tanδ) of the films were measured. The results show that the BFO-PT layers are mainly perovskite structured; the film deposited under 6.665 Pa exhibits low leakage current, low dielectric loss (0.017-0.041) and saturated hysteresis loop with polarization (Pr) value and coercive field (Ec) of 3 μC/cm2 and 109 kV/cm.
文摘目的:探究观察3M Single Bond Universal粘接系统对前牙E-max铸瓷贴面修复的远期疗效。方法:选择2017年5月-2019年5月笔者医院收治的需前牙E-max铸瓷贴面修复患者63例(患牙113颗)为研究对象,均行经典贴面修复,根据粘接系统的不同将患者分为观察组(患者21例,患牙40颗,采用3M Single Bond Universal粘接系统)、对照1组(患者21例,患牙36颗,采用VariolinkⅡ粘接系统)、对照2组(患者21例,患牙37颗,采用BISCO CHOICE 2粘接系统)。治疗后三组均于1周、3个月、12个月时进行随访,观察三组治疗后1周、3个月、12个月内贴面修复效果、贴面修复失败率及不良反应发生率。结果:术后1周,三组患者均无失败案例;对照1组存在2颗修复体保存完整度为Ⅰ级的患牙,对照2组存在3颗修复体保存完整度为I级的患牙,观察组未存在该类患者;术后12个月,观察组存在1颗修复体保存完整度Ⅱ级患牙,对照1组存在1颗保存完整度I级患牙,3颗修复体保存完整度Ⅱ级患牙,对照2组存在2颗保存完整度I级患牙,3颗修复体保存完整度Ⅱ级患牙。三组患者治疗效果比较,差异无统计学意义(P>0.05);术后1周、3个月、12个月三组贴面修复失败率比较,差异无统计学意义(P>0.05);随访期间内,三组患者不良反应情况比较差异均无统计学意义(P>0.05)。结论:对于前牙E-max铸瓷贴面修复患者,选取合适的适应证,并做好备牙步骤,3M Single Bond Universal与经典VariolinkⅡ粘接系统及BISCO CHOICE 2粘接系统治疗效果并无显著差异,值得在临床推广使用。