排序方式: 共有67条查询结果,搜索用时 15 毫秒
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硅藻土多孔陶瓷膜管的研制和性能表征 总被引:1,自引:0,他引:1
以硅藻土为主要原料,用注浆成型工艺制备出管状硅藻土多孔陶瓷。该材料具有孔隙率高,孔径小,孔径分布狭窄等特点。当原料中淀粉含量从0增至50%时,样品的孔隙率由37%增至74%(其中,淀粉的贡献值由0增至56%)。平均孔径由0.54μm增至4.94μm,最大孔径则由0.91μm增至7.21μm。当原料中淀粉含量为10%和30%时,膜管的氮气通量分别为:58.68和127.74m3m-2h-1bar-1。 相似文献
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La0.7-xSmx+0.02Ca0.3CrO3-δ(0≤x≤0.4) powders with A-site excessive perovskite structure were synthesized by auto-ignition process and characterized. X-ray diffraction (XRD) patterns of samples after sintering at 1400℃ for 4 h were indexed as tetragonal structure. The relative densities were all above 96% although decreased slightly with the increasing content of samarium, indicating that the excessive A-site element was helpful to enhance their sinterability. Conductivities of the specimens in air increased with increasing content of samar-ium. The conductivity of La0.6Sm0.12Ca0.3CrO3-δ was 33.6 S/cm in air at 700 ℃ which was about 1.7 times as high as that of La0.7Ca0.3CrO3-δ (20.1 S/cm). Average thermal expansion coefficients (TECS) of the specimens increased from 11.06×10-6 to 12.72×10-6 K-1 when x in-creased from 0 to 0.4, and they were close to that of Y doped ZrO2 (YSZ). La0.7-xSmx+0.02Ca0.3CrO<3-δ>(0.1≤x≤0.3) were good choices for in-termediate temperature solid oxide fuel cells (IT-SOFCs) interconnect materials. 相似文献
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复合氧化物Cd2Sb2O7—x的制备及其应用新进展 总被引:1,自引:0,他引:1
回顾了镉-锑复合氧化物的制备及其应用的进展情况,介绍了一种采用化学共沉淀制备具有缺陷烧绿石结构的Cd2Sb2O7-x超微纯相粉的方法,并发现该法所得产物具有良好的气敏性能。 相似文献
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半导体材料γ-Fe_2O_3超细粉的制备与改性 总被引:4,自引:0,他引:4
以Fe(NO3)3·9H2O2为源物质,乙二醇为溶剂,用Sol-gel法制备了平均粒径为10nm的γ-Fe2O3和掺Y2O3的γ-Fe2O3超细粉,并同时对样品的热稳定性、物相、微结构和气敏性能作了分析和测定.结果表明,掺入适量Y2O3后能使γ-Fe2O3的相变温度提高到775℃,这将使γ-Fe2O3基气敏元件的稳定性得到改善.两种超细粉制成的旁热式厚膜气敏元件对H2和CO几乎不敏感,而对C2H5OH、C2H2、液化石油气(LPG)和汽油则有较高的灵敏度. 相似文献
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掺Sb2O3 的SnO2与Fe2O3厚膜的
电学行为及气敏特性 总被引:2,自引:0,他引:2
介绍掺入Sb_2O_3后的SnO_2和FeO_3(由γ-Fe_2O_3-热处理得到)气敏厚膜元件电阻和灵敏度的变化规律:对于SnO_2基元件,Sb_2O_3具有低掺杂(<4%wt)电阻变小,高掺杂电阻增大的作用,但气敏性降低;对于Fe_2O_3基元件,掺入Sb_2O_3后不但能降低电阻、提高气敏性,而且对丙酮的选择性也增强.指出Sb~(3+)→Sb~(5+)变化对上述效应起着重要作用,并探讨了Fe_2O_3基元件表面化学吸附增强的原因. 相似文献
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CdO对In2O3电导和气敏性能的影响 总被引:2,自引:1,他引:1
为探索新型CdO-In2O3材料的气敏性能,用化学共沉淀法制备了CdO掺杂的In2O3微粉,研究了CdO掺杂对In2O3电导和气敏效应的影响。结果表明CdO和In2O3间能形成有限固溶体In2-CdxO3(0≤x≤0.02);In1.98Cd0.02O3x的电导比纯In2O3小得多;900℃下热处理4h所得的x(CdO)为2%的In2O3传感器在183℃工作温度下,对45μmol·L–1C2H5OH的灵敏度达276、响应–恢复时间只有3s和180s。有望开发为一类新型酒敏材料。 相似文献