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11.
The mechanism of X-ray waveguide-resonance propagation or the radiation superstream model, which can become the ground of X-ray nanophotonics, is discussed briefly. Some attention is devoted to features consideration of the simplest devices characterized by the waveguide-resonance transportation of X-ray beams. The experimental data showing the user possibilities of a simplest waveguide-resonators application for diffractometry are presented. We discuss the main reasons to improve the metrological characteristics for total reflection X-ray fluorescence (TXRF) analytical method in case when the target exciting beam is formed by a waveguide-resonator. Some problems appearing during the waveguide-resonator application are formulated. 相似文献
12.
The contrast of interference pattern formed by two circularly polarized waves and by a linearly polarized wave and a circularly polarized one is discussed. The results are compared with that by two linear beams. It shows that the use of circular light in holographic fabrication of three-dimensional periodic microstructures may remove the necessity of beam ratio and polarization optimization needed in the interference of three linear noncoplanar beams and improve the uniform contrast of resultant pattern simultaneously. 相似文献
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选择不同电离电位的基体元素K、Na、La、Y和Mg,比较研究了它们对分析元素谱线强度的影响,其影响程度与谱线激发电位及基体元素电离电位有定量的相关关系。碱金属基体(K、Na)和非碱金属基体(La、Y和Mg)对分析元素检出限、背景强度及其相对标准偏差的影响显著不同,后者的记忆效应也大于前者。La的电离电位与Na相差不大。但其基体效应与Y相似,表明墓体效应与基体元素的化学性质有关。 相似文献
16.
A. Dönni P. Fischer B. Roessli H. Kitazawa 《Zeitschrift für Physik B Condensed Matter》1994,93(4):449-454
Nuclear and magnetic structures of an annealed polycrystalline sample of the heavy-fermion compound CePd2Al3 prepared by arc-melting were investigated by neutron powder diffraction. The chemical structure corresponds well to the ordered hexagonal PrNi2Al3-type structure. The antiferromagnetic structure of CePd2Al3 with an ordered magnetic moment
Ce=0.47(2)
B at saturation is remarkably similar to that in the heavy fermion superconductor UPd2Al3. The additional incommensurate magnetic structures reported previously both for UPd2Al3 and CePd2Al3 are not observed in the present sample of CePd2Al3. At 1.4 K the magnetoresistivity of CePd2Al3 measured up to 14 T indicates only one field-induced phase transition at 3.0 T. 相似文献
17.
偏最小二乘法在原子吸收光谱分析中的应用——钴和铟的同时测定 总被引:4,自引:1,他引:3
本文用偏最小二乘法(PLS)校正了火焰原子吸收分析In252.137nm对Co252.136nm的吸收线重叠干扰,对混合样中Co和In的含量进行了测定,结果令人满意。 相似文献
18.
The possibility of lasing without inversion on the 1079.8 nm line of a HeNe laser is investigated. It is shown that a modified double- scheme can be realized by use of the 877.9 nm line for introducing Zeeman coherence. It is shown experimentally that Zeeman coherence can enforce laser action, even if the inversion is below threshold. A different choice of the polarization of the driving beam can result in suppression of laser action above threshold. The underlying mechanisms are examined. On the 611.8 nm line, laser action below threshold inversion is obtained with the driving beam tuned to 824.9 nm (up-conversion). 相似文献
19.
本文以Na、ca、Al、Zn作为主要基体元素,在不同ICP发射光谱仪上考察了20多条分析谱线受到的干扰情况,初步总结了基体干扰效应的一般规律。结果表明,在常用分析条件下,一般金属元素具有与易电离元素类似的基体效应,即在较低观察区域对测定谱线信号产生增感,而在正常观察区域产生抑制;从增感转向抑制的零干扰点主要出现在感应圈上方8~14mm的观察区域,这一结果为实际分析条件的优化提供了有益的依据。 相似文献
20.
D. Charalambidis J. A. D. Stockdale C. Fotakis 《Zeitschrift für Physik D Atoms, Molecules and Clusters》1994,32(3):191-196
The modification of multiphoton ionization spectra through third harmonic generation in focused laser beam geometries is reported. A strong enhancement of the ionization peaks corresponding to the decay of thenf' autoionizing series of Kr and the observation of a double resonance in Xe, which is missing in low atomic density spectra, is shown to originate from excitation channels involving absorption of third harmonic photons. This excitation is demonstrated to occur in a significantly extended volume outside the focal region, thus strongly increasing the ionization yield. 相似文献