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101.
用于双色全息存储(Fe,Cu)∶LiNbO3晶体的参量优化计算 总被引:1,自引:0,他引:1
在确定Cu在LiNbO3晶体中对应于365 nm和633 nm的激发系数、复合系数、光伏系数的基础上,采用龙格库塔(Runge-Kutta)数值方法理论研究了双掺杂(Fe,Cu)∶LiNbO3晶体的深浅能级的掺杂组分比、氧化还原状态对双色全息存储的记录灵敏度和动态范围的影响,并探讨了同时取得尽可能大的灵敏度和动态范围的晶体条件。结果表明,为了同时得到较大的记录灵敏度和动态范围,在实际应用中选用浅能级掺杂浓度为5.0×1025m-3,深能级掺杂浓度为3×1024~3×1025m-3之间的弱氧化晶体是合适的。 相似文献
102.
全息光存储以其高密度、大容量、高速并行数据存取而成为光存储领域的一个重要研究方向。生物光致变色材料———菌紫质是一种新型可擦重写全息记录介质。实验证明了使用菌紫质薄膜进行角度复用和偏振复用全息存储的可行性。利用菌紫质的光致变色特性,采用90°角度复用全息存储光路,在BR-D96N薄膜样品同一位置上实现了6幅全息图存储,并分别读出了无串扰的再现像。利用菌紫质薄膜的光致各向异性进行了偏振复用全息存储,在BR-D96N薄膜样品的同一位置上存储了两幅正交偏振光记录的图像,用原参考光再现和偏振片选择,可分别读出这两幅图像。 相似文献
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104.
R. Otto P. Hecht H.-G. Könnecke H. Koch H. J. Naumann W. Winzer 《Isotopes in environmental and health studies》2013,49(12):425-429
This paper reviews ways in which radioactive tracer techniques can he used to improve the efficiency of a caprolactam production plant, Residence time spectra and material distributions in different parts of the plant were measured by application of sodium 24, bromine 82 and technetium 99m. The investigations led to improved cumeneoxidators and gave useful informations on the catalytic decomposition of the phenolic tar and the hydrogenation process of phenol. It could he shown that the construction of the lactam extractor must he varied and the results of the tracerexperiments made in the distillation unit contributed to a higher quality of the final product. 相似文献
105.
G. Dersch R. Beckmann G. Feige T. Lund P. Vater R. Brandt 《Isotopes in environmental and health studies》2013,49(6):303-304
A recent article interpreted the experiment by Dersch et al. on the formation of 24Na in 40Ar + Cu interactions in a very simple manner. The results from emulsion experiments performed with 3.6 AGeV 22Ne were adapted for the interpretation of the experiments with 1.8 AGeV 40Ar. The model used the same mean value for the energy of minimum ionizing protons and pions at all angles. It is argued that a more complex approach is needed for a satisfactory interpretation. 相似文献
106.
Nesrine Mechi Ismahen Ben Khemis Houcine Dhaou Slim Zghal Abdelmottaleb Ben Lamine 《Chinese Journal of Physics (Taipei)》2018,56(2):449-467
The Mg50Ni45Cr5 alloy for hydrogen storage is prepared by mechanical alloying. First, using the X-ray diffraction (XRD) and the scanning electron microscopy (SEM) we examine the morphology and the structure of the substrate. The obtained results highlight the effectiveness of this alloy in loading hydrogen as it is a nanocrystalline and a ductile one. Second, we attempt to justify these expectations using the statistical physic, precisely the model monolayer with two levels of energy, in modeling a hydrogen absorption and desorption isotherms on Mg50Ni45Cr5 alloy at four temperatures T?=?275?K, T?=?300?K, T?=?325?K and T?=?350?K. The model has six physicochemical parameters deduced from the fitting of the isotherms, they are divided by two categories of steric and energetic parameters. Thanks to these parameters we compare the absorption and desorption processes, in order to highlight the hysteresis phenomenon encountered during the hydrogen sorption. 相似文献
107.
Long-term, high resolution holographic storage has been achieved in side-chain liquid crystalline polyesters with high diffraction efficiency. The information can be completely erased by heating the film to about 80°C. The modular architecture of the polyesters permits a varition in the length of the main- and side-chains and the substituents of the azo chromophore. Each of these has a profound influence on the storage properties of the polyesters. In this article, we examine the influence of the length of the side-chains, the probe-beam-polarization dependence of the observed signal on the interface and the crystalline vs. amorphous nature of the films for optical storage. 相似文献
108.
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110.
Europium (Eu+) ions were confined in a Paul trap and detected by non-destructive method. Storage time of Eu+ ions achieved in vacuum was improved by orders of magnitude employing buffer gas cooling. The experimentally detected signal
was fitted to the ion response signal and the total number of ions trapped was estimated. It is found that the peak signal
amplitude as well as the product of FWHM and the peak signal amplitude is proportional to the total number of trapped ions.
The trapped ion secular frequency was swept at different rates and its effect on the absorption line profile was studied both
experimentally and theoretically. 相似文献