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971.
We examined the thermal stability of amorphous silicon oxycarbide (SiOC) and crystalline Fe composite by in situ and ex situ annealing. The Fe/SiOC multilayer thin films were grown via magnetron sputtering with controlled length scales on a surface-oxidized Si (100) substrate. These Fe/SiOC multilayers were in situ or ex situ annealed at temperature of 600 °C or lower. The thin multilayer sample (~10 nm) was observed to have a layer breakdown after 600 °C annealing. Diffusion starts from low groove angle triple junctions in Fe layers. In contrast, the thick multilayer structure (~70 nm) was found to be stable and an intermixed layer (FexSiyOz) was observed after 600 °C annealing. The thickness of the intermixed layer does not vary as annealing time goes up. The results suggest that the FexSiyOz layer can impede further Fe, Si and O diffusion, and assists in maintaining morphological stability.  相似文献   
972.
A significant advantage of the folded wave traveling wave tube (TWT) is simple coupling structure. In millimeter wave band, owing to higher frequency, linear double taper can be used as impedance transformer. The design method and calculation results for the folded waveguide TWTs in K-band are given.  相似文献   
973.
Quantum Fluctuations in a Mesoscopic Inductance Coupling Circuit   总被引:9,自引:0,他引:9  
Starting from the equation of motion of a mesoscopic inductance coupling circuit,the quantum fluctuations of charge and current in the circuit are investigated inboth the eigenstates of the system and the squeezed vacuum state. The resultsshow that there exist quantum fluctuations of the charge and current in bothcases, and the fluctuations in each component circuit are connected.  相似文献   
974.
刘明生  李铣 《波谱学杂志》1998,15(6):539-542
筋骨草甾酮C是分布于植物中的植物甾酮类化合物,具有抗氧化的作用.本文标定了该化合物中所有的碳信号,并通过13C-1H COSY和1H-1H COSY技术纠正了文献中氢信号归属的错误.  相似文献   
975.
血卟啉单甲醚对DNA损伤的拉曼光谱研究   总被引:9,自引:3,他引:9  
刘颂豪  孟耀勇 《光学学报》2000,20(4):29-532
利用激光拉曼光谱技术研究了新型光敏剂血卟啉单甲醚对DNA(脱氧核糖核酸)分子的光动力学损伤。结果表明:DNA分子由典型B型构型变成了一种修饰过的B型。连接碱基对的氢键被部分打断,碱基堆叠也有所与解。碱基本身也遭到了破坏,有脱氨基现象发生。腺嘌呤和胞嘧啶对血咔啉单甲醚的光动力学损伤更敏感。  相似文献   
976.
The refractive index nf, extinction coefficient kf and thickness df of a dip coated film are measured by using p-polarized laser beams. A sample is oblique illuminated with a p-polarized laser beam, and then two reflected beams, from the front and back surfaces, are received with a detector. After measuring their intensity ratio versus the angle of incidence, it is convenient to obtain the parameters of the film by means of data fitting. The films of polymethyltriethoxy silane (PMTES), which were made on a BK-7 glass substrate by dip coating, were measured. The method is non-contact, non-destructive and has the advantages of simplicity of both equipment and understanding. It is also shown that the values measured by this method are coincident with those measured by ellipsometry.  相似文献   
977.
Five natural graphites with different rhombohedral phase (3R phase) content have been investigated as anode materials for rechargeable lithium-ion batteries. The reversible capacity varies from 250 mA h/g to 350 mA h/g for the same intercalation conditions depending on the content of the 3R-phase. With increasing rhombohedral phase in the graphite, the intercalation capacity will be high. A peak at about 10 mV in the cyclic voltammograms (CV) of a sample with a large 3R-phase content is caused by lithium ions occupying boundaries between the rhombohedral (3R) phase and the hexagonal (2H) phase and is responsible for a capacity exceeding the theoretical value.  相似文献   
978.
A novel surface plasmonic waveguide structure composed of chiral medium and 2D material is proposed. The universal direction-dependent dispersion relation is obtained, which covers the combinations between 2D materials with in-plane isotropy or anisotropy and the surroundings with or without chirality. The tunability of the behavior of surface plasmon polaritons with the chirality of environment and the doping level are investigated. The averaging effect of chirality in both sides of 2D material is unveiled. Besides, the transverse spin of SPPs in the Chiral-2D material structure is explored and the asymmetric distribution of the transverse spin depends mainly on the contribution from the magnetic spin instead of the electric spin. These features are advantageous for the manufacture of novel photonic devices and the development of sensors techniques for the chiral environment.  相似文献   
979.
在柱状边界条件下将对柱侧面的曲面积分表示成一维积分,同时还给出了椭圆积分的计算方法,由对空间立体角积分的算例可知,其计算的速度有了显著的提高.  相似文献   
980.
本文报道用分子束外延技术生长的Cd1-xMnxTe/Cd1-yMnyTe超晶格样品在80K下的光调制反射谱实验结果,观测到11H,22H,33H和11L等激子跃迁结构。计及晶格失配导致的应力效应,对子能级结构进行了理论计算。  相似文献   
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