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991.
Large Piezoelectricity and Ferroelectricity in Mn‐Doped (Bi0.5Na0.5)TiO3‐BaTiO3 Thin Film Prepared by Pulsed Laser Deposition 下载免费PDF全文
Qianru Lin Rui Ding Qian Li Yee Yan Tay Danyang Wang Yun Liu Yizhong Huang Sean Li 《Journal of the American Ceramic Society》2016,99(7):2347-2353
Mn‐doped (Bi0.5Na0.5)0.94Ba0.06TiO3 (MnBNBT) thin films were prepared on SrRuO3 (SRO)‐coated (001) SrTiO3 (STO) single crystal substrates by pulsed laser deposition under different processing conditions. Structural characterization (i.e., XRD and TEM) confirms the epitaxial growth of STO/SRO/MnBNBT heterostructures. Through the judicious control of deposition temperature, the defect level within the films can be finely tuned. The MnBNBT thin film deposited at the optimized temperature exhibits superior ferroelectric and piezoelectric responses with remanent polarization Pr of 33.0 μC/cm2 and piezoelectric coefficient d33 of 120.0 ± 20 pm/V. 相似文献
992.
Li2O–MgO–TiO2 ternary system is an important microwave dielectric ceramic material with excellent properties and prospect in both scientific research and application. A phase diagram of the Li2O–MgO–TiO2 ternary system was established in this article, based on earlier research results and our present work. Microwave dielectric properties with compositions in different regions of the phase diagram have been analyzed. We found that the 0.33 Li2MgTi3O8–0.67 Li2TiO3 ceramics sintered at 1200°C exhibited excellent dielectric properties: Q × f value = 80 476 GHz (at 7.681 GHz), εr = 24.7, τf = +3.2 ppm/°C. We also designed two ceramic systems in the Li‐rich region of the Li2O–MgO–TiO2 ternary system, which received little attention in the past decades, because many excellent single‐phase ceramics, such as Li2MgTiO4, Li2MgTi3O8 and MgTiO3, have been found in the Ti‐rich region. The ceramic systems have low sintering temperatures but also relatively poor dielectric properties. 相似文献
993.
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995.
结合中国中材国际工程股份有限公司设计的某10000t/d熟料生产线的回转窑挡轮装置,介绍了挡轮装置的优化设计,其中创新设计了不同与以往1个挡轮的3个挡轮的设置;对其挡轮装置的结构也作了优化,采用了3组轴承,使挡轮受力更加合理,寿命延长。2012年该10000t/d回转窑装备被评为科技进步二等奖,至今已应用于国内外多条生产线,均取得了良好的业绩和效果。 相似文献
996.
997.
采用夏比摆锤冲击试验对同种焊接及焊后热处理工艺条件下的F92/F22异种钢焊接接头焊缝冲击性能进行了研究。结果显示,1号试样的冲击吸收能量(63 J)不足相同工艺条件下2号试样冲击能量(130 J)的1/2。通过扫描电子显微镜(SEM)和能谱(EDS)分析了冲击断口的形貌特征和微区成分,发现在1号试样冲击断口的裂纹形成区存在大小约25μm的复合氧化物夹杂。采用有效投影面积模型计算引发裂纹萌生的临界夹杂物尺寸,分析了夹杂物对F92/F22异种钢焊接接头冲击性能的影响,并确定了该夹杂是造成1号试样冲击吸收能量显著下降的主要原因。因此,应采取适当的工艺措施减少其内部的缺陷,以提高该异种钢焊接接头的冲击性能。 相似文献
998.
Composite films based on poly(lactic acid)(PLA) filled with modified multiwalled carbon nanotubes (MWCNTs) were prepared by casting/solvent evaporation technique and investigated for their properties and structures. MWCNTs were modified by coupling agent KH570 which can improve the dispersion of MWCNTs and then enhance the comprehensive properties of PLA. The influences of modified conditions, including the amounts of KH570, the reaction temperature and time, were analyzed. And also the structures and properties of composite films were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), fourier transform infrared (FTIR) and thermogravimetric analysis (TG). The two components of the composite films, WMCNTs and PLA, had excellent compatibility. The addition of MWCNTs modified by coupling agents KH570 was beneficial for the crystallization of PLA, and the toughness of composite films was also improved. When the reaction temperature was 70 °C, reaction time was 6 h, and the amount of KH570 was 3 % respectively, the obtained composite films had the perfect comprehensive properties. 相似文献
999.
Yu-Wen Zhang Fan-Lin Zeng Chen-Chen Yu Cheng-Zhang Wu Wei-Zhong Ding Xiong-Gang Lu 《稀有金属(英文版)》2016,35(9):723-728
The permeability and stability of Sm0.7Sr0.3CoO3?δ (SSCO) regarding the special requirements for carbon capture and storage (CCS) application were investigated. Pure CO2 was used as the sweep gas at 900 °C, leading to that the oxygen permeation flux decreases by about 34 %. Several cycles of changing the sweep gas between helium and CO2 indicate the good reversibility of this degradation. Both carbonate formation and adsorption of CO2 on the membrane surface are responsible for the degradation of the membrane performance. The better CO2 resistance results from the substitution of Sm for Sr due to the higher acidity of Sm2O3 (1.278) than that of SrO (0.978) and a discontinuous layer of carbonate. 相似文献
1000.