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191.
蔡祥宝 《南京邮电大学学报(自然科学版)》1993,(1)
本文应用四元数形式的相对论性波动方程,对电子在相互垂直的均匀电场和磁场中的运动进行了分析,并求出了在忽略算符EQEuCi的近以条件下的能量本征值和本征函数。 相似文献
192.
大熊猫曲细精管(生精小管)内有丰富的微血管分布,分支形成微血管系,支持细胞附着其上,共同构成曲细精管内的微支架。微血管系的存在,对曲细精管内进行血液供应和物质交换、睾丸的高代谢率和高血流量、维持睾丸的低温值,以及曲细精管的正常生精机能有着重要意义。 相似文献
193.
In situ potential mapping of space charge(SC) layer in a single Ga N nanowire(NW) contacted to the Au metal electrode has been conducted using off-axis electron holography in order to study the space distribution of SC layer under electric biases. Based on the phase image reconstructed from the complex hologram the electrostatic potential at the SC layer was clearly revealed; the SC width was estimated to be about 76 nm under zero bias condition. In order to study dynamic interrelation between the SC layer and bias conditions, the variation of the electrostatic potential due to change of the SC widths respond to the different bias conditions have also been examined. The measured SC layers are found to vary between68 nm and 91 nm, which correspond to the saturated SC layers at the Ga N-Au contact under the forward and reverse bias conditions, respectively. By plotting the square widths of the SC layer against the applied voltages, donor density of Ga N NWs was derived to be about 4.3*10~6cm~(-3). Our experiments demonstrate that in-situ electron holography under electric fi eld can be a useful method to investigate SC layers and donor density in single NW and other heterostructures. 相似文献
194.
The assumption that the electron temperature is approximately equal to the ion temperature is not rational during the high frequency (HF) heating in low ionosphere region. Thus, using the theoretical formula of incoherent scatter spectra with collisional plasma, the incoherent scatter data are analyzed during ionosphere heating at 91.7 km height on August 15th 2006. The enhancements of electron temperature are obtained, and the incremental percent is up to 37% and 46% at the universal time of 10:22 and 10:30, respectively. By using the same initialization value, the ionosphere heating process is simulated by Ohmic theory and the experimental results are basically consistent with the simulation. 相似文献
195.
Majid Niaz Akhtar Nadeem Nasir Muhammad Kashif Noorhana Yahy Mukhtar Ahm Ghulam Murtaz Muhammad Azhar Khan M.H.Asif A.Sattar R.Raz M . Saleem S.N.Khan 《自然科学进展(英文版)》2014,24(4):364-372
Electromagnetic signals in deep reservoir are very weak so that it is difficult to predict about the presence of hydrocarbon in seabed logging(SBL) environment.In the present work,Mn0.8Zn0.2Fe2O4 nanoferrites were prepared by a sol–gel technique at different sintering temperatures of450 °C,650 °C and 850 °C to increase the strength of electromagnetic(EM) antenna.XRD,FESEM,Raman spectroscopy and HRTEM were used to analyze the phase,surface morphology and size of the nanoferrites.Magnetic properties of the nanoferrites were also measured using an impedance network analyzer.However,nanoferrites sintered at 850 °C with initial permeability of 200 and Q factor of 50 were used as magnetic feeders with the EM antenna.Lab scale experiments were performed to investigate the effect of magnetic field strength in scale tank.SPSS and MATLAB softwares were also used to confirm the oil presence in scale tank.It was observed that the magnitude of the EM waves for the antenna was increased up to 233%.Finally,the correlation values also show 208% increase in the magnetic field strength with the presence of the oil.Therefore,antenna with Mn0.8Zn0.2Fe2O4 nanoferrites based magnetic feeders can be used for deep water and deep target hydrocarbon exploration. 相似文献
196.
197.
为提高等离子体密度和工质气体电离率,本文采用螺旋天线产生的螺旋波激励Ar等离子体,并利用射频补偿Langmuir探针分析了等离子体的离子密度和电子温度特征.试验结果表明,气压增加的同时,随着功率的升高,螺旋波等离子体出现放电模式转换,提前进入螺旋波放电模式.在1.0 Pa压强下,当射频功率达到400 W时,等离子体进入螺旋波放电模式,此时扩展区域的等离子体密度超过1×1018 m-3.电子密度在放电管中心区域最高,并沿径向逐渐降低.本文的研究结果将为大体积H2螺旋波等离子体提供依据和经验. 相似文献
198.
199.
王德松 《河北科技大学学报》1996,(4)
研究了电子束预辐照维尼纶纤维接枝丙烯酸,考察了预辐照剂量、反应时间、单体的质量分数、反应温度和摩尔盐对接枝反应的影响,以及接技后纤维力学性能的变化,并对电子束预辐照接枝反应机理进行了初步探讨。 相似文献
200.
山东蒿属花粉形态研究及其在分类上的意义 总被引:2,自引:1,他引:2
用光学显微镜和扫描电镜,对蒿属10种植物花粉形态进行了观察,花粉粒在赤道面观呈近球形或近长球形,极面观呈三裂圆形,具三孔内,外壁具有小刺状纹饰,花粉粒极轴长12.29μm-17.91μm,赤道轴宽12.44μm ̄16.88μm,研究结果表明,本属花粉形态特征支持传统分类的属及属以下各级水平(包括亚属,组和种级)的分类。 相似文献