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设M是Nobusawa意义下的Г-环,S.Kyuno定义了环M_2=其中R,L分别是M的右、左算子环.本文首先刻画了环M_2的本原理想与Ja-cobson根.其次引进了一类新的Г-环称为PM Г-环,建立了Г-环M、矩阵Г_(n,m)-环M_(m,n)、Г-环M的右(左)算子环R(L)、M-环Г及M_2的PM性质之间的关系.最后,给出了Г-环一般形式的Jacobson性质,Jacobson性质、Brown-McCoy性质以及PM性质为其特殊情况. 相似文献
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金属纳米线是未来纳米电子器件中的重要组成部分,因此研究单根金属纳米线的电学性质具有重要的意义。相对于单根纳米线电学性质的移位测量,原位测量精确度更高,结果更可靠。目前,国际上用于原位电学性质测量的单根纳米线的最小直径为80 nm,更小直径的纳米线很难在纳米孔道中生长,其电化学生长动力学过程还不清楚,电阻率数据缺失。本文在单个蚀刻离子径迹孔道中利用电化学沉积技术成功生长了单根Cu纳米线,其直径仅为64 nm,为目前同方法最细。在此基础上,首次测量了该纳米线的电输运性质并获得了其电阻率数值。研究结果表明,利用电导法可以监测模板中单个孔道的形成和扩孔的动力学过程以及最终的孔径大小。电化学沉积时,沉积电流与沉积时间曲线清晰地揭示了纳米线的沉积动力学过程。I-V曲线研究显示Cu纳米线具有典型的金属特性。其电阻率为3.46 μ?·cm,约是Cu块体材料电阻率的两倍。电阻率增大可能与电子在晶界和表面处的散射有关。Metal nanowires, as one of the most crucial components of nanoelectronic devices in the future, have attracted enormous attention. Therefore, it is of great significance to investigate the electrical properties of single metal nanowires. Herein, the single Cu nanowire with diameter of 64 nm was successfully prepared by using single-ion track template method combined with electrochemical deposition approach, and its I-V curve was measured. Such a diameter represents the thinnest one as comparing the reported ones obtained by the same method. The results illustrated that the process of formation and growth, as well as the final diameter of single nanochannel in template can be monitored and measured by conductance method. During the electrochemical deposition, the dynamic evolution of the deposition of nanowire can be clearly reflected through the deposition current and deposition time. At the same time, I-V measurements reveal that the Cu nanowire has typical metallic characteristic. For the first time, the resistivity of such a thin nanowire is obtained and its resistivity is 3.46 μ?·cm which is around twice that of Cu bulk materials. The increase of resistivity is believed coming from finite size effects and may be related to the electrons scattering at the grain boundaries and surfaces. 相似文献
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本文证明了下面主要结果: Ⅰ.设R是一个根,则R是一个强半单根的充分必要条件是满足对任意环A的每一个理想I,I=I+R(A)成立。Ⅱ.设R是一个根,A是任意环,则下面条件等价。(1)?I1,I2?A有I1∩I2=I1∩I2; (2)?I?A,TI是L(A)的凸子格且β(A)是一个下半格,其中TI1∩TI2=TI1∩I 相似文献
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设M是Nobusawa意义下的Г-环,S.Kyuno定义了环M_2=其中R,L分别是M的右、左算子环.本文首先刻画了环M_2的本原理想与Ja-cobson根.其次引进了一类新的Г-环称为PM Г-环,建立了Г-环M、矩阵Г_(n,m)-环M_(m,n)、Г-环M的右(左)算子环R(L)、M-环Г及M_2的PM性质之间的关系.最后,给出了Г-环一般形式的Jacobson性质,Jacobson性质、Brown-McCoy性质以及PM性质为其特殊情况. 相似文献