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CeO2添加剂对等离子ZrO2涂层抗热震性的影响 总被引:2,自引:0,他引:2
在ZrO2陶瓷涂层中加入适量的CeO2,使陶瓷涂层的抗热震性能得到提高,这主要是由于CeO2的加入,涂层的微小孔隙增加、涂层产生细微的网状裂纹,增加了微裂纹密度,从而降低了徐层的弹性模量,释放了涂层中的应力,提高了涂层的裂纹失稳扩展时的临界温差ΔTc,并可阻止裂纹沿单方向的快速扩展,使涂层的抗热震起裂性能和抗热震失效能力得到提高。其中,CeO2加入量为9%效果最佳,过量加入CeO2,会过早地促进裂纹的扩展、断裂,不利于提高涂层的抗热震性能。 相似文献
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FSM- 16,MCM- 4 1和 SBA- 15等具有高规则性的二维六角晶格结构的多孔硅可由不同的硅酸盐或有机硅氧化物结合表面活性剂制备而成 ,孔径的大小可根据表面活性剂的不同烷基链长和有机膨胀剂的添加量加以控制 ,最大可分别达到 10 0 ,10 0和 150 ,但其晶格的规则性则随孔径的增大而降低。我们发现了用层状硅酸盐Kanemite制备的 FSM- 16和来自硅酸钠的 MCM- 4 1,其表面阴离子度比用四甲氧基硅烷 ( TMOS)制备的 SBA- 15高得多。如将在等电点以下呈阳离子性的生物酶插入多孔硅中 ,则由于形成的离子间相互作用和氢键结合力 ,可得到结合得十分稳定的生物 /无机陶瓷结合体。特别是孔径比生物酶的尺寸 ( 4 6 )稍大的情况下结合最稳定 ,其结合量可达 2 0 % ,以此结合体作为有机酸化反应的催化剂 ,呈现了很高的反应活性。此方法在环境工程上将有十分广阔的应用前景。 相似文献
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胶片判读后的原始测量数据包含着一定的高频无序随机误差,仅仅用加权平滑及差商法对数据加工计算,势必严重影响运动分析可靠性。本文将讨论数据滤波平滑的必要性,介绍在胶片判读处理中几种行之有效的数据滤波平滑方法。它们是:最小二乘曲线拟 相似文献
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对从海带种苗床赤斑中分离出来的抗生菌进行了DNA热动力学分类地位的研究。DNA的G+C含量测定表明:G+C克分子%含量在类单胞菌属(Alteromonas)范围内。DNA复性测定Cot1/2值表明;分离菌0125与红色类单胞菌(Alteromonas rubra ATCC 29570)同源性为71%,分子量相同为2600×103道 相似文献
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Improved light extraction of GaN-based light-emitting diodes with surface-textured indium tin oxide electrodes by nickel nanoparticle mask dry-etching
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GaN-based light-emitting diodes (LEDs) with surface-textured indium tin oxide (ITO) as a transparent current spreading layer were fabricated.The ITO surface was textured by inductively coupled plasma (ICP) etching technology using a monolayer of nickel (Ni) nanoparticles as the etching mask.The luminance intensity of ITO surface-textured GaN-based LEDs was enhanced by about 34% compared to that of conventional LED without textured ITO layer.In addition,the fabricated ITO surface-textured GaN-based LEDs would present a quite good performance in electrical characteristics.The results indicate that the scattering of photons emitted in the active layer was greatly enhanced via the textured ITO surface,and the ITO surface-textured technique could have a potential application in improving photoelectric characteristics for manufacturing GaN-based LEDs of higher brightness. 相似文献
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Magnetocaloric effect and critical behavior of the Mn-rich itinerant material Mn_3GaC with enhanced ferromagnetic interaction
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We revisit the reversible magnetocaloric effect of itinerant ferromagnet Mn3GaC near the ferromagnetic to paramagnetic phase transition by adopting the experimental and theoretical methods and critical behavior of Mn-rich Mn3GaC with an enhanced FM interaction.Landau theory model cannot account for temperature dependent magnetic entropy change which is estimated from thermal magnetic methods only considering magnetoelastic coupling and the electron-electron interaction,apart from molecular mean-field model.Critical behavior is studied by adopting the modified Arrott plot,Kouvel-Fisher plot,and critical isotherm analysis.With these critical exponents,experimental data below and above Tc collapse into two universal branches,fulfilling the single scaling equation m=f±(h),where m and h are renormalized magnetization and field.Critical exponents are confirmed by Widom scaling law and just between mean-field model and three-dimensional Heisenberg model,as the evidence for the existence of long-range ferromagnetic interaction.With increasing the Mn content,Tc increases monotonously and critical exponents increases accordingly.The exchange distance changes from J(r)~r^-4.68 for x=0 to J(r)~r^-4.71 for x=0.08,respectively,which suggests the competition of the Mn-Mn direct interaction and the itinerant Mn-C-Mn hybridization.The possible mechanism is proposed. 相似文献