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叙述了自发参量下转换辐射定标技术的发展历程,技术原理以及在光学计量学中的应用,并介绍了国外这一领域的进展。 相似文献
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对 I P与 A T M 相结合的两种技术模型——重叠模型和集成模型的基本构成、原理进行了阐述,并对其优缺点进行了分析,提出 I P 与 A T M 相结合是 Internet 发展的最终趋势。 相似文献
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采用气相色谱法测定碳酸甘油酯粗产品中碳酸甘油酯和残余甘油的含量。选择HP1701毛细管柱,程序升温及四甘醇内标物作为色谱条件,在此条件下碳酸甘油酯和残余甘油能很好地分离。碳酸甘油酯和甘油的线性范围分别为23.30~116.6 g.L-1和3.70~18.40 g.L-1。方法的回收率在99.1%~100.9%之间,相对标准偏差(n=6)在0.61%~1.93%之间。 相似文献
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There are two general methods in radiometric calibration of detectors, one is based on radiation sources and the other based on detectors. Because the two methods need to establish a primary standard of high precision and a transfer chain, precision of the standard will be reduced by extension of the chain. A new calibration method of detectors can be realized by using correlated photons generated in spontaneous parametric down-conversion (SPDC) effect of nonlinear crystal, without needing transfer chain. Using 351.1-nm output of a tunable laser to pump β-barium borate (BBO) crystal, an absolute calibration experimental system of single photon detectors based on correlated photons is performed. The quantum efficiency of photomultiplier (PMT) at 702.2 nm is measured by the setup. Advantages of this method over traditional methods are also pointed out by comparison. 相似文献
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