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Signal distortion due to the non-uniform response of the detector degrades the measurement accuracy of most metrology instruments. In this Letter, we report a newly developed calibration source system for reference-based non-uniformity correction using a laser source, a fiber, and a diffusive module. By applying the Monte Carlo simulation, we show that the transmittance of the system highly depends on the cavity reflection of the diffusive module. We also demonstrate the use of this system to achieve a flat field at a very low non-uniformity(less than 0.2%) with proper illumination intensity, which most costly commercial integrating sphere systems traditionally cannot provide. 相似文献
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过渡金属催化的烯烃的二聚反应是碳-碳键形成的重要反应之一.因其原料易得、原子经济、且具有很好的工业应用前景而已得到深入、广泛的研究.系统研究了钌催化N-乙酰基烯胺与烯烃的二聚反应,发现在钌氢络合物RuHCl(CO)(PCy_3)_2的催化下可实现系列N-乙酰基α-芳基乙烯胺1与芳基乙烯4的高化学选择性和区域选择性二聚,并以高达99%的收率得到头对尾的多取代烯酰胺5.依据反应结果及反应中观测到的现象,提出了芳基乙烯4先与活化的钌氢中间体发生插入反应形成类烯丙基中间体,然后与N-乙酰基α-芳基乙烯胺1发生二聚反应生成多取代烯酰胺5的可能机理,并对反应中观测到的现象进行了合理的解释. 相似文献
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利用热蒸发法在N型硅片表面成功制备出大面积SiO_2纳米线和SiO_2纳米棒结构。采用X射线粉末衍射(XRD),扫描电子显微镜(SEM),X射线能量色散谱(EDX),拉曼光谱(RS)和光致发光(PL)对合成的产物进行了表征。结果表明,用此方法生长的SiO_2纳米材料,其结构和形貌与生长参数关系密切,随着沉积温度降低纳米线长度变短,最后呈现出棒状结构。此外,还研究了SiO_2纳米结构独特的光学性质。该研究对改善光电子半导体器件的性能应用具有重要意义。 相似文献
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Path protections have become increasingly important for current mesh optical networks because fast restorations in generalized multiprotocol label switching(GMPLS) networks are uncertain.However,setting up additional disjoint paths to protect connections leads to more path setup blocking and signaling collisions.We analyze signaling collisions,path blocking and blocking probability,as well as calculate node-to-node blocking probabilities.A signaling-based path-segment protection(PSP) is proposed,which integrates segment protections and path protections as well as enhances the performance of path protections and ring protections.The setup of PSP connections causes less blocking probability than the setup of path protection connections in the simulations. 相似文献
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提出了光学检测聚丙烯酰胺溶液的方法,利用TU-1901/1900双光束紫外可见分光光度计、IRPrestige-21傅立叶变换红外光谱仪测量5~600mg·L-1浓度范围内聚丙烯酰胺溶液的透射光谱,研究了其在波段190~900nm和400~4 000cm~(-1)的光谱特性,进行了其浓度的反演分析。研究表明:聚丙烯酰胺溶液在200~300nm和400~920cm~(-1),2 986~3 684cm~(-1)范围存在较强吸收特性,其透光度在220nm,2 623cm~(-1)处有一定的线性关系;在紫外波段基于2,3和4个透光度测量值反演其未知浓度的计算误差最大值分别为6.98%,2.34%和0.79%。 相似文献