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951.
952.
We carry out a systematic study on the fusion-fission and evaporation residue excitation functions for the reactions of 6,7Li, 9Be, 10,11B + 209Bi and 6,9Li, 9Be + 208Pb, in which the projectiles are loosely bound and have low threshold energies against breakup. The fusion cross sections are calculated by the coupled-channel model. The compound nuclei decay are analyzed with the standard statistical model. The fission and evaporation residue excitation functions are well reproduced by our calculations, proving the validity of the standard statistical model in describing the compound nuclei decay in these characteristic reactions. For the compound nuclei with A=215-220 and Z=86-88, the liquid drop fission barriers need to be scaled by 0.80-1.02 to reproduce the experimental data. And a decreasing trend of the scaling factor with increasing fissionability parameter Z2/(50A) is found. 相似文献
953.
Ying Li Gaoyang Zhao Jian Su Erfeng Shen Yang Ren 《Applied Physics A: Materials Science & Processing》2011,104(4):1069-1073
Top electrode (TE) material on the resistive switching behavior of (TE)/CuO/SnO2:F/Si substrate has been studied. We investigated the switching properties of CuO films deposited by sol-gel process. Two
kinds of top electrode (TE) material on the resistive switching behaviors have been studied. The nonpolar and bipolar resistive
switching phenomenon was observed in CuO thin films with different top electrodes. The filamentary mechanism was used to explain
the two kinds of resistive switching behaviors. For the Pt/CuO/ATO device, it showed the nonpolar resistive switching where
conducting path is formed and disappear due to the oxygen vacancy. For the Cu/CuO/ATO device, the resistance reduction is
due to the existing Cu to form conduction Cu-rich pathways. An opposite bias takes the existing Cu back to the Cu electrode
to its high-resistance state. CuO thin films are also observed by XRD, AFM and XPS. 相似文献
954.
视场角(FOV)是仅次于最大光程差、决定高分辨率傅里叶红外光谱仪(FTIRS)仪器线型函数(ILS)的重要因素.由于光学设计和装调原因,理论为圆形FOV的扩散光束,到达探测器端时,其水平和垂直方向上的FOV值往往不再严格对等.对此,提出了以椭圆形面光源取代传统文献中的圆形面光源来反映这种非对等性,并结合最大光程差参数,... 相似文献
955.
本文从FPGA器件内部最基本的CMOS单元出发,分析了器件功能失效时反相器输出波形随累积剂量的变化关系,进而研究Altera SRAM型FPGA器件60Co γ射线辐照后的总剂量辐射损伤效应.实验结果表明:由于场氧漏电和结构漏电的影响,随着累积剂量的增加输出波形发生畸变,峰峰值变为原来的十分之一左右,但输出波形还有相对的高低电平;同时,输出高电平不能保持原有的状态,迅速地向低电平转换,并且转换速度随着累积剂量的增加而加快,输出低电平相对初始值有一定程度抬高;由于栅氧厚度变薄,输出波形
关键词:
60Coγ')" href="#">60Coγ
总剂量辐射损伤效应
SRAM型FPGA
CMOS单元 相似文献
956.
In this paper we study polynomial normal forms and smooth (C∞) classification of one kind of diffeomorphisms which have infinite many resonant relations but are finitely determined. We derive a complete list of normal forms of all such germs with arbitrary degeneracy of their nonlinear parts. 相似文献
957.
从双循环半群的同余关系出发,讨论了幂等元所在的同余类,证明了双循环半群上的一类同余ρd(d∈N)与其逆子半群之间的相互唯一确定关系,并对这种同余做成的集合进行了刻画,证明了这种同余做成的格与自然数集在某种偏序下做成的格同构,得到了一些有意义的结果. 相似文献
958.
959.
This is a subsequent work of our previous one in [25]. Let the nonlinear terms of non-autonomous parabolic problems with singular initial data satisfy subcritical and critical growth conditions. We first establish the existence of uniform attractors in W1,r(Ω), 1<r<N, for the family of processes corresponding to the equations with external forces being translation bounded but not translation compact. Then, we prove the existence of pullback attractors in Lr(Ω) and W1,r(Ω), respectively, for the process corresponding to the equation with the weaker assumption on the external force than previous one. Finally, we investigate the robust of attractors and establish the existence of pullback exponential attractors for the process acting in Lr(Ω) and W1,r(Ω), respectively. 相似文献
960.
Frequency-hopping spread spectrum and direct-sequence spread spectrum are two main spread coding technologies in communication systems. Frequency-hopping sequences are needed in FH-CDMA systems. In this paper, a construction of optimal sets of frequency-hopping sequences using cyclotomy and the Chinese remainder theorem is introduced. It generalizes some earlier constructions, and produces new optimal sets of frequency-hopping sequences. 相似文献