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991.
992.
We present a high power red-green-blue (RGB) laser light source based on cascaded quasi-phasematched wavelength conversions
in a single stoichiometric lithium tantalate. The superiority of the experimental setup is: the facula of the incident beam
is elliptical to increase interaction volume, and the cavity was an idler resonant configuration for realizing more efficient
red and blue light output. An average power of 2 W of quasi-white-light was obtained by proper combination of the RGB three
colors. The conversion efficiency for the power of the quasi-white-light over pump power reached 36%. This efficiency and
powerful RGB laser light source has potential applications in laser-based projection display et al. 相似文献
993.
Based on the fact that a hard aperture function can be expanded into a finite sum of complex Gaussian functions, the approximate analytical expressions for the output field distribution of an anomalous hollow beam (AHB) passing through an apertured fractional Fourier transform (FRT) system are derived. By using the approximate analytical formulae and diffraction integral formulae, the propagation properties of an AHB in circular and rectangular apertured FRT system are studied numerically. The results show that this method provides a convenient tool for studying the propagation properties of an AHB passing through apertured FRT system, and the apertured FRT system can be applied to laser beam shaping conveniently. 相似文献
994.
995.
996.
Ta2O5/SiO2 dielectric mirrors deposited by ion beam sputtering (IBS) are studied. The multi-shot laserinduced damage threshold (LIDT) and its dependence on the number of shots are investigated, after which we find that the multi-shot LIDT is lower than that of single-shot. The accumulation effects of defects play an important role in the multi-shot laser damage. A simple model, which includes the conduction band electron production vsa multiphoton and impact ionizations, is presented to explain the experimental phenomena. 相似文献
997.
Keyu Jiang Qin Fan Tong Chen Changxi Miao Zhenji Zhao Xielong Yang 《Hyperfine Interactions》2012,205(1-3):81-85
Two series of Fe-K catalysts for dehydrogenation of ethylbenzene to styrene were prepared with different amounts and different compounds of the additional element Ce. M?ssbauer spectroscopy has been used to determine the Fe compound in the catalyst and to investigate the effect of Ce. The catalytic properties of the catalysts have also been measured. The results show that the element Ce in the catalyst is favorable to form the predecessor of the catalytic active phase, the compound KFe11O17 and that the optimal percentage of CeO2 is 8%~15% in the catalyst which is favorable to the formation of KFe11O17 and to get better catalytic properties. 相似文献
998.
Fayou Zhao 《Mathematische Nachrichten》2012,285(10):1294-1298
Fu and Lu et al. 7 showed that the commutator $\mathcal {H}_{\beta ,b}$ generated by the fractional Hardy operator and a locally integrable function b is bounded on the homogenous Herz spaces if and only if b is a central bounded mean oscillation function. We show that their result is optimal by giving a counterexample. 相似文献
999.
1000.
In this paper, we study a generalized Nicholson??s Blowflies model with feedback control and multiple time-varying delays. Under proper conditions, we employ a novel proof to establish some criteria to guarantee the global exponential convergence and permanence of this model. Moreover, we give two examples to illustrate our main results. 相似文献