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51.
The feasibility of employing a NiO-yttria stabilized zirconia (YSZ) nano-powder slurry spin coating (NSC) to fabricate a thin film (≤ 1 μm) electrolyte solid oxide fuel cell (TF-SOFC) on a relatively rough surface of the support is investigated in this study. The NiO-YSZ nano-powder with ~ 200 nm particle size was synthesized by a single-step glycine nitrate process and super-apex milling. Through varying the NiO-YSZ nano-powder slurry condition by changing polymeric additives, a leveled surface of the spin coated layer which enabled to overcome the surface roughness of the bulk ceramic processed anode substrate was obtained. On the NSC layer, TF-SOFC components with flat profiles could be fabricated using pulsed laser deposition. A stable open circuit voltage of 1.04 V was obtained with these thin film components on an anode support with a rough surface.  相似文献   
52.
We present results of a fairly complete study on which dopants M result in single-phase U1−xMxPt3 samples. The resulting new samples. M = Y, Lu, Sc, Hf, Zr, have been characterized by low temperature magnetic susceptibility and specific heat for x 0.07. Based on a previously proposed model, the c/a ratios of the present alloys would be expected to result in magnetic behavior as observed in U1−xThxPt3 and U(Pt1−xPdx)3. On the contrary, no magnetism is found; the Sc-doped samples actually show a suppression of spin fluctuations. A new proposal is made to explain which properties are critical for the magnetic behavior of UPt3, as well as its doped derivatives.  相似文献   
53.
讨论了用瑞利法和邓柯莱法计算转轴临界转速的两种方法方法,将计算结果与临界转速的精确值作了对比,说明算法是简单方便的。  相似文献   
54.
通过X射线衍射.磁测量和M(?)ssbauer谱测定了Nd(Fe1-Cox)10V2的结构和磁性.结果表明,Nd(Fe1-xCox)10V2(x=0,0.05,0.10,0.15,0.20)化合物的晶体结构均为ThMn12型结构;随着 Co含量x的增大,晶格常数将单调减少.Co原子的替代将导致化合物各个Fe晶位上的磁超精细场值Bhf逐渐增加.Co部分取代Nd(Fe1-xCox)10V2中的Fe原子时.将择优占据8i铁晶位.取向样品NdFe10V2的热磁曲线和变温M(?)ssbauer谱研究结果表明.该化合物在T=120K条件下存在自旋重取向现象.  相似文献   
55.
56.
We show that a quantum lattice gas approach can provide a viable means for numerically solving the classical Maxwell equations. By casting the Maxwell equations in Dirac form, the propagator may be discretized, and we describe how the accuracy relative to the time step may be systematically increased. The quantum lattice gas form of the discretization is suitable for implementation on hybrid classical-quantum computers. We discuss a number of extensions, including application to inhomogeneous media.   相似文献   
57.
罗广圣  李长全  叶梅 《稀土》2002,23(3):69-71
研究了 Mn替代 Co对 Tb2 Co1 7金属间化合物结构和磁性的影响。 X射线衍射表明 :Tb2 Co1 7- x Mnx(x=0 ,1,2 ,3,4)化合物均为 Th2 Zn1 7型菱方结构 ;晶胞参数和单胞体积均随 Mn含量的增加而线性增大。磁性测量表明 :Tb2 Co1 7- x Mnx(x=0 ,1,2 ,3,4)化合物室温为面各向异性 ;居里温度 Tc随 Mn含量 x的增加而线性降低 ;自旋重取向温度 Tsr随 Mn含量 x的增加而线性降低 ;饱和磁化强度 Ms起初随 Mn含量增加而缓慢增大 ,当 x>3时随 Mn含量增加而迅速减小。  相似文献   
58.
A multi-terminal InAs-based lateral spin-valve tunnelling device is presented, which enables individual electrical characterization of all spin-valve components in two-terminal configuration. Both the spin-valve and the non-local geometry are available for studying spin-dependent transport. Furthermore, we propose a measurement geometry in which the spin-dependent contact resistance of the sensor electrode can be measured in three-terminal configuration. Longitudinal magnetoresistance in spin-valve geometry reveal hysteresis loops of 1 mΩ deflection as known from Hall magnetometry. In non-local geometry a polarity-dependent current–voltage characteristic at 2 K is observed. This can be understood in terms of a superposition of a diffusive resistive component with a polarity-dependent ballistic component.  相似文献   
59.
建立了同侧双进口蜗向回转通道内三个分离区域内分级效率的公式,理论上分析了同侧双进口蜗向回转通道有利于提高旋风器的分离性能。以收集效率为基础,部分实验验证了这一结论。  相似文献   
60.
Effect of cobalt substitution on the band gap and absorption coefficient of the BiFeO3 thin films formed on quartz substrate by low cost spin coating method have been investigated. BiFe1−xCoxO3 (x=0, 0.03, 0.06 and 0.10) thin films are polycrystalline and it retains the rhombohedral distorted perovskite structure up to 10 mole % of Co substitution. Smooth and compact surface morphology with uniform size particles are observed in SEM micrographs. Narrowing and broadening of band gap is observed as a function of Co content. Two strong emission peaks at ~2.51 eV and ~2.38 eV are recorded for all films with noticeable change in intensity. Results obtained from the optical absorption and photoluminescence spectroscopy experiments have shown that there exists an inverse correlation between the variation in the band gap and the concentration of oxygen vacancies. Band gap decreased by ~100 meV and absorption coefficient increased by 28% at the wavelength of 375 nm in 6 mole % Co substituted thin film and these observations are necessary requirements to improve the efficiency of photovoltaic devices.  相似文献   
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