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961.
本文描述了一种Beheim的改进型方案,用以提高强度型光纤传感器的稳定性,可用于多种物理量的测量.给出了应用于相对位移测量的实验结果. 相似文献
962.
光子晶体光纤及其应用 总被引:3,自引:1,他引:2
光子晶体作为一种新兴的材料 ,将会对整个光子学和光子产业领域产生深远的影响 ,而其最重要的应用之一———光子晶体光纤已经在很多科研技术领域得到了应用 .文章综述了光子晶体光纤的研究进展 ,给出其分类 ,并重点介绍了光子晶体光纤在超短脉冲、光频测量、光纤通信等科研领域的重要应用以及未来的发展前景 相似文献
963.
J. Schneider D. Hauschild Ch. Frerichs L. Wetenkamp 《International Journal of Infrared and Millimeter Waves》1994,15(11):1907-1922
We report highly efficient CW fiber lasers at 2.7µm in an Er3+-doped and weakly Pr3+-codoped fluorozirconate fiber. The fiber lasers were pumped in three pump wavelength ranges around 650, 795 and 980 nm. Higher output powers of nearly 30 mW and a broader potential tuning range of 180 nm compared to Er3+ singly doped fiber lasers are demonstrated. Laser efficiencies of more than 13% were achieved. It is shown that the fiber laser can be tuned to longer wavelengths by increasing the pump power or, in certain cases, by increasing the pump wavelength. Furthermore, we present the wavelength tuning of the Er3+:Pr3+-codoped system by an external grating. The relationships between laser wavelength and pump rates are described, and the reasons for the improvements with Pr3+-codoping are given. 相似文献
964.
LI Zhaohui 《Chinese Journal of Lasers》2002,11(5):321-323324
A novel Yb3+-doped fiber ring cavity laser pumped by a 977 nm laser diode is presented with its output laser wavelength of 1060 nm. Based on a fiber Bragg grating (FBG), the laser exhibits 0.20 nm line-width, 7.5 mW laser output power, 40 dB signal-to-noise ratio (SNR) and 66% slope efficiency.This paper proposed a ray-tracing model for the Martinez stretcher, derived the calculation formulae for the stretcher of a grating-spherical mirror system and discussed the error for the total dispersion resulted from the spatial dispersion. The calculated results show that the error could be ignored for the beam returned to the stretcher for the second pass in the wavelength range of 750 nm and 850 nm. 相似文献
965.
Ch. Frerichs 《International Journal of Infrared and Millimeter Waves》1994,15(4):635-649
Efficient operation of a cw fluorozirconate fiber laser at 2.7µm pumped at 980 nm is reported. Threshold powers below 1 mW, efficiencies up to 9.3% and output powers up to 6 mW were observed. CW laser operation occurred although the lifetime of the upper laser level is shorter than that of the lower laser level and excited state absorption from the upper laser level additionally weakens population inversion. The mechanisms clarifying cw operation of this self-terminating transition are discussed. The laser operates at several lines between 2.70 and 2.82µm, whereby the operating wavelength increases with increasing pump power. 相似文献
966.
967.
968.
969.
Mahmoud Rajabian Charles Dubois Miroslav Grmela Pierre J. Carreau 《Rheologica Acta》2008,47(7):701-717
Rheological properties of suspensions of fibers in polymeric fluids are influenced by fiber–polymer interactions. In this
paper, we investigate this influence from both experimental and modeling standpoints. In the experimental part of this investigation,
we have changed the fiber–polymer interactions by treating the surface of the fibers. The resulting effects are observed using
scanning electron microscopy and dynamic mechanical analysis techniques and quantified from the measurements of the viscosity
in the start-up of shear flows and dynamic tests in the linear viscoelastic range region. The results are interpreted with
the help of a mesoscopic rheological model developed for suspensions of fibers in viscoelastic fluids. 相似文献
970.
水样中铜,铅,镉的巯基棉富集火焰原子吸收测定 总被引:4,自引:0,他引:4
翟贵仙 《光谱学与光谱分析》1992,12(1):119-122
在测定水样中铜、铅及镉的时候用巯基棉在采样现场富集简便快速,且灵敏准确,避免了样品运送的不便和萃取富集的繁琐。 相似文献