排序方式: 共有6条查询结果,搜索用时 31 毫秒
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A. Cig J. Ma
ka M. Mair G. Gritzner G. Plesch V. Zrubec 《Physica C: Superconductivity and its Applications》1999,320(3-4):267-276
The effects of the thallium and mercury content x on the as-sintered and post annealed samples of MxPb0.4Sr1.6Ba0.4Ca2Cu3O8+δ {M: Tl (0.32≤x≤0.74) or Hg (0.18≤x≤0.68)} have been studied by magnetization and transport measurements. For Tl-1223 we have found the optimum Tl doping level to be x=0.53 regarding the grain properties, the content of superconducting phase, the first penetration field Hplwl, the transport (Jctr), magnetic intergrain (JcM) and intragrain (Jcg) critical current densities. The critical temperature Tc of the as-sintered Tl-1223 sample decreased with increasing Tl content. Post-annealing in oxygen improved the Tc for Tl contents of x≥0.53 and had generally positive effects on the critical current densities. The intergrain properties of the Hg-1223 samples were much worse than those of the Tl-based superconductors. 相似文献
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Sr-doped SnO2 thick film gas sensors were prepared for domestic liquefied petroleum gas (LPG) determination down to several ppm levels
using the screen-printing technique. Characterization of Sr-doped SnO2 thick film was investigated by XRD, XPS and DTA-TGA analyses. The sensitivity, selectivity, sintering temperature, and static
and dynamic measurement were investigated. The results showed that the Sr-doped SnO2 thick film sensor is suitable for several ppm levels LPG determination because of the high sensitivity (S = 12.7 to 10 ppm
LPG). The dynamic measurements showed that the sensor exhibited high sensitivity and selectivity to domestic LPG at 210–300 °C. 相似文献
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San Ping Jiang 《Journal of Solid State Electrochemistry》2007,11(1):93-102
Activation effect can be defined as the enhancement of the electrochemical performance or activity of the solid oxide fuel
cell cathodes such as Sr-doped LaMnO3 (LSM) with the polarization/current passage treatment under fuel cell operation conditions. In this paper, the activation
effect of the cathodic polarization/current passage on the O2 reduction reaction of the LSM-based cathodes is reviewed. In addition to the activation effect, cathodic polarization/current
passage also has a significant effect on the microstructure of the LSM electrodes and the morphology between the LSM electrode
and Y2O3-ZrO2 electrolyte interface. A mechanism involving the incorporation of SrO species into the LSM lattice and the formation of oxygen
vacancies is proposed for the activation effect of the polarization. 相似文献
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含Sr纳米晶粒二氧化钛多孔微球的制备与表征 总被引:1,自引:0,他引:1
半导体光催化剂引发的光化学反应被广泛地应用到有毒有机污染物的深度处理、 光有机合成、 能量的转化与存储等研究领域[1~5]. 其中, 利用半导体二氧化钛光催化降解有机污染物受到了广泛的关注. 近年来, 通过掺杂和负载重金属-[6]和金属氧化物[7]等方法来改性二氧化钛, 虽然在一定程度上提高了其光催化活性, 但是没有彻底解决催化剂回收和重复使用的问题.本文通过溶液浸渍和高温处理的方法合成了含Sr纳米晶粒二氧化钛多孔微球, 在保证了二氧化钛微球粒径较大、 易于回收和重复使用等优点的同时, 使其降解活性艳蓝的活性提高了2倍, 具有较为广阔的应用前景. 相似文献
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对Eu1-xSrxMnO3 (x=0.4, 0.5, 0.6, 0.7) 体系的磁结构进行了系统的研究. 通过核磁共振实验, 磁化测量, 并结合电输运测量结果表明, Sr的掺入使得 EuMnO3反铁磁母相中出现铁磁相. 铁磁相和反铁磁相的竞争导致样品在低温下的自旋玻璃行为.分析认为, Eu0.4Sr0.6MnO3和Eu0.3Sr0.7MnO3的磁结构在低温下呈现更加复杂的特征, 主要源于铁磁团簇的形成以及无序相的存在. 相似文献
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