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71.
饶坚  黄姗  刘全慧 《大学物理》2005,24(12):36-37
定态下氢原子平均电流密度只有一个沿纬线的分量非零,本文在这一结果的基础上计算了氢原子的总电流,发现它与经典力学中行星运动的开普勒定律之间有明确的对应关系.  相似文献   
72.
采用分子碎片法合成了5,9,14,18,23,27,32,36-八丁氧基-2,3-萘酞菁铜,利用元素分析、红外及紫外可见光谱进行了表征。配合物的电子吸收光谱表明:新配制的氯仿溶液中萘酞菁铜的Q带H聚集体和单体的吸收峰在758、854nm处,5h后单体和H聚集体的吸收峰基本消失,出现了798和909nm的错位H/J聚集体以及960nm的J聚集体吸收,12h后主要以795nm的H聚集体形式存在。  相似文献   
73.
朱峰  董珊  承刚 《中国物理 B》2011,20(7):77103-077103
The global greenhouse effect makes it urgent to deal with the increasing greenhouse gases.In this paper the performance of MgO-decorated carbon nanotubes for CO 2 adsorption is investigated through first principles calculations.The results show that the MgO-decorated carbon nanotubes can adsorb CO 2 well and are relatively insensitive to O 2 and N 2 at the same time.The binding energy arrives at 1.18 eV for the single-MgO-decorated carbon nanotube adsorbing one CO 2 molecule,while the corresponding values for O 2 and N 2 are 0.55 eV and 0.06 eV,respectively.In addition,multi-molecule adsorption is also proved to be very satisfactory.These results indicate that MgO-decorated carbon nanotubes have great potential applications in industrial and environmental processes.  相似文献   
74.
A gas-filled type of recoil separator for heavy element research was installed at an experimental hall of RIKEN Linear Accelerator facility to realize getting higher intensity of primary beam and long beam time. Performance of the separator was studied using target recoils and various nuclear reactions. The results show the high performance of the separator for heave element research. As an application of the GARIS, production and identification of an isotope of the 110th element 271[110] have been performed using the 208Pb(64Ni,1n)271[110] reaction. Three decay chains coincide well both in decay times and energies with the ones reported by the group of SHIP experiment at GSI, Germany. Our results provide a confirmation of the synthesis of an isotope 271[110] of element 110.  相似文献   
75.
The detection of saccharides in biological media is of great current importance for the monitoring of disease states. We have previously reported that solutions of boronic acid-functionalized macrocycles form acyclic oligomeric materials in situ. The oligomers contain fluorescent xanthene moieties. Current efforts are aimed at modulating the spectroscopic responses of these materials for the analysis of specific sugars. We describe conditions whereby the xanthene boronic acids exhibit high colorimetric fructose selectivity. In contrast, at physiological levels selective glucose monitoring can be achieved via fluorescence. Additionally, we describe a method which exhibits promise for detecting both glucose and fructose at dual wavelengths in the UV-Vis region. Mechanistic rationale for each of these findings is presented.  相似文献   
76.
Five novel lanthanide (Eu3+, Tb3+, Gd3+, Sm3+ and Dy3+) complexes with 2, 2'-bipyridine-N, N'-dioxide (bipyO2) were synthesized and characterized by elemental analysis, IR spectrum. The triplet state energy of bipy O2 was determined to be 22275 cm(-1) with the phosphorescence spectrum of bipy O2 and its gadolinium complex. The photophysical properties of these complexes indicated that the triplet state energy of the ligand is suitable for the sensitization of the luminescence of Eu3+, Tb3+, Sm3+ and Dy3+, especially of Tb3+.  相似文献   
77.
四边形位置敏感探测器(PSD)的传统位置计算公式不能正确反映实际光斑位置,存在严重的枕形失真,需要进行复杂的修正.基于Lucovsky方程的解析解,提出了改进型的PSD计算公式,结果表明,采用改进型公式可以使用少量数据完成对PSD的非线性修正,极大地提高PSD中央大部区域的线性度.对于1×1 cm2的PSD,在60%光敏面的区域内均方根误差小于3 μm,非线性度小于0.05%,该公式适用于所有的四边形PSD,对于PSD的实际应用具有重要意义.  相似文献   
78.
A program is modeled to describe nitriding depth by a new mixing laser and plasma beams nitriding (LPN) technique. The model extends the transport of ions in matter (TRIM) program by adding temperature and energy factors into the energy function. The nitriding depths and nitrogen distribution in substrate were calculated by Monte Carlo program. There is a good agreement between calculation and experiment results at different laser energy intensities, scanning velocities and nitrogen ion energies respectively. Moreover, the nitriding process diagrams by LPN technique are shown from calculation results.  相似文献   
79.
80.
The accumulation effects in high-reflectivity(HR) HfO2/SiO2 coatings under laser irradiation are investigated.The HR HfO2/SiO2 coatings are prepared by electron beam evaporation at 1 064 nm.The laser-induced damage threshold(LIDT) are measured at 1 064 nm and at a pulse duration of 12 ns,in 1-on-1 and S-on-1 modes.Multi-shot LIDT is lower than single-shot LIDT.The laser-induced and native defects play an important role in the multi-shot mode.A correlative theory model based on critical conduction band electron density is constructed to elucidate the experimental phenomena.  相似文献   
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