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991.
992.
Br2分子里德堡态的高分辨转动谱研究 总被引:2,自引:2,他引:0
用窄线宽(0.08cm^-^1)脉冲可调谐紫外激光和(2+1)多光子电离方法测量了Br2的里德堡(Rydberg)态光谱,在70000-71500cm^-^1范围内,获得了溴分子[П3/2]4d振动系列,测量(v',v”)=(1,0),(2,0)的高分辨振转谱,得到其转动常数B’79-81分别为0.08832和0.08805cm^-^1,并提出此系列的角动量量子数Ω应为1。 相似文献
993.
Mössbauer and magnetic susceptibility measurements were used to study the magnetic properties of Ln1.9Sr1.1Cu2O6 (Ln=Pr,Nd) and La2SrCu2O6 materials. These compounds were prepared by solid-state reaction and crystallize in a tetragonal structure, space group I4/mmm with two formula units per unit cell. There is only one crystallographic site for Cu atoms, which form a double layer of CuO5 pyramids. These compounds are not superconducting, but we show, using Mössbauer spectroscopy (MS) on iron doped samples and susceptibility measurements, that the Cu planes order antiferromagnetically. The hyperfine fields on iron nuclei at 4.2 K extend from 472 kOe for La2SrCu2O6 to 501 kOe for Nd1.9Sr1.1Cu2O6. The ordering temperaturesT
N are: R20, 190, and 250 K for Ln=La, Pr and Nd, respectively. 相似文献
994.
Hong-Shuo Li J. M. Cadogan Jian-Min Xu S. X. Dou H. K. Liu 《Hyperfine Interactions》1994,94(1):1929-1935
A study of the Nd-Fe-Ti phases at the Fe-rich end of the phase diagram has been carried out using57Fe Mössbauer spectroscopy, scanning electron microscopy (SEM) and energy dispersive X-ray analysis (EDAX). In particular,57Fe Mössbauer spectroscopy has been used to characterize the phases present in these samples. In addition to the two well-known 217 and 112 phases, twonovel phases have been identified, with compositions denoted by3–29 and9–94, which are closely linked to the orthorhombic ScFe6Ga6-type and the hexagonal TbCu7-type structures, respectively. The possible crystal structures of these new phases will be discussed in terms of the dumbbell substitution sequence in the CaCu5 structure. 相似文献
995.
996.
997.
Origin and manifestation of the anharmonic potential felt by an ion-cloud in an actual Paul trap 总被引:1,自引:0,他引:1
X. Luo X. Zhu K. Gao J. Li M. Yan L. Shi J. Xu 《Applied physics. B, Lasers and optics》1996,62(4):421-426
The anharmonic potential felt by a single-species ions confined in a rf quadrupole trap which results from a non-ideal trap configuration and the charge distribution of the ion cloud is studied. The rf resonance-absorption spectra are explained by a Duffing oscillator and a representation of the line-shape parameter is derived. For > 0.77, the electric signals will exhibit hysteresis. The relation with the anharmonic potential is discussed. 相似文献
998.
999.
1000.
Lijun Zhang Shanjia Xu 《International Journal of Infrared and Millimeter Waves》1996,17(10):1735-1747
The finite element method is combined with the mode-matching method and the multi-mode network method to analyze the scattering and radiation characteristics of a class of planar dielectric waveguide discontinuities. Unlike the conventional method to treat the radiation as a source-field problem, in the present approach, the dispersion characteristics of dielectric guided-wave structures are calculated first, and then the radiation problem is transferred to the propagation problem of a series of surface-waves and space waves from the viewpoint of scattering, thus the analysis is tremendously simplified. 相似文献