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71.
CeOs4Sb12晶体中由于导电电子与Ce3+ 4f1电子之间存在c-f杂化作用导致费米面附近存在能量间隙.这种c-f近藤相互作用和能量间隙是理解CeOs4Sb12物理性质,如近藤绝缘体行为、Ce3+磁矩在低温下猝灭以及重费米性等电、磁性质的关键.当用LAM-D中子谱仪对粉末CeOs4Sb12进行测量时,可以得到不同温度下CeOs4Sb12的非弹性中子散射谱.结果表明CeOs4Sb12中存在近藤相互作用,其作用强度为3.1 meV,证实了CeOs4Sb12为近藤绝缘体.中子测量得出CeOs4Sb12德拜温度为317 K.
关键词:
非弹性中子散射
填充式方钴矿
近藤绝缘体 相似文献
72.
Chong-Guang Cao Zhong-Peng Yang Xian Zhang 《Journal of Applied Mathematics and Computing》2002,10(1-2):101-109
We extend two inequalities involving Hadamard products of positive definite Hermitian matrices to positive semi-definite Hermitian matrices. Simultaneously, we also show the sufficient conditions for equalities to hold. Moreover, some other matrix inequalities are also obtained. Our results and methods are different from those which are obtained by S. Liu in [J. Math. Anal. Appl. 243:458–463(2000)] and B.-Y. Wang et al. in [Lin. Alg. Appl. 302–303: 163–172(1999)]. 相似文献
73.
The breakthrough and stoichiometric SO2 adsorption efficiencies of a biomass supported Na2CO3 system (80 wt %Na2CO3/straw) have reached 48.9% and 80.6% respectively at a desulfurization temperature of 80℃. 相似文献
74.
75.
76.
77.
Haifeng Yang Guangming XieTianguang Chu Long Wang 《Nonlinear Analysis: Theory, Methods & Applications》2006
In the paper, commuting and stable feedback design for switched linear systems is investigated. This problem is formulated as to build up suitable state feedback controller for each subsystem such that the closed-loop systems are not only asymptotically stable but also commuting each other. A new concept, common admissible eigenvector set (CAES), is introduced to establish necessary/sufficient conditions for commuting and stable feedback controllers. For second-order systems, a necessary and sufficient condition is established. Moreover, a parametrization of the CAES is also obtained. The motivation comes from stabilization of switched linear systems which consist of a family of LTI systems and a switching law specifying the switching between them, where if all the subsystems are stable and commuting each other, then the total system is stable under arbitrary switching. 相似文献
78.
以CF4和C6H6的混合气体作为气源,在微波电子回旋共振化学气相沉积(ECRCVD)装置中制备了氟化非晶碳薄膜(aC:F),并在N2气氛中作了退火处理以考察其热稳定性.通过傅里叶变换红外吸收谱和紫外可见光谱获得了薄膜中CC双键的相对含量和光学带隙,发现膜中CC键含量与光学带隙之间存在着密切的关联,在高微波功率下沉积的氟化非晶碳膜具有低的光学带隙和较好的热稳定性.
关键词:
氟化非晶碳膜
光学带隙
退火温度
热稳定性 相似文献
79.
Hongbo Zhang Rui Wang Kaixin Chen Han Yang Daming Zhang Maobin Yi Guoquan Wang Zhenchang Ma 《Optics & Laser Technology》2002,34(4):283-286
A new method, based on zero point of longitudinal electric field, was used to determine the spatial resolution of external electro-optic (EO) probing equipment. Considering the diffraction of Gauss beam, the result of external EO probing was simulated which was in accordance with the experiment. A spatial resolution <1 μm was demonstrated initially in our equipment using 650 nm laser diode as probe beam and semi-insulating GaP as probe tip. 相似文献
80.
Liyue Liu Yingge Yang Yafei Zhang 《Physica E: Low-dimensional Systems and Nanostructures》2004,24(3-4):343-348
The electrical conductivity was investigated for multi-walled carbon nanotubes (MWNTs) dissolved in chloroform and toluene, respectively. The electrical conductivity remarkably increased with increase in the content of MWNTs, which is in accordance with Archie's equation . Furthermore, a hypothesis of the electronic transport process was proposed to explain the difference between the solution and the solid compound. In addition, the temperature dependence of the electrical conductivity shows that log σ vs. 1/T exist in a good linear relationship. The activation energy of the electrical conductivity decreased with increase in concentration and an inflexion was observed at 60 °C in MWNT/toluene solution. 相似文献