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Upgrade of beamline BL08B at Taiwan Light Source from a photon‐BPM to a double‐grating SGM beamline
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Jih‐Young Yuh Shan‐Wei Lin Liang‐Jen Huang Hok‐Sum Fung Long‐Life Lee Yu‐Joung Chen Chiu‐Ping Cheng Yi‐Ying Chin Hong‐Ji Lin 《Journal of synchrotron radiation》2015,22(5):1312-1318
During the last 20 years, beamline BL08B has been upgraded step by step from a photon beam‐position monitor (BPM) to a testing beamline and a single‐grating beamline that enables experiments to record X‐ray photo‐emission spectra (XPS) and X‐ray absorption spectra (XAS) for research in solar physics, organic semiconductor materials and spinel oxides, with soft X‐ray photon energies in the range 300–1000 eV. Demands for photon energy to extend to the extreme ultraviolet region for applications in nano‐fabrication and topological thin films are increasing. The basic spherical‐grating monochromator beamline was again upgraded by adding a second grating that delivers photons of energy from 80 to 420 eV. Four end‐stations were designed for experiments with XPS, XAS, interstellar photoprocess systems (IPS) and extreme‐ultraviolet lithography (EUVL) in the scheduled beam time. The data from these experiments show a large count rate in core levels probed and excellent statistics on background normalization in the L‐edge adsorption spectrum. 相似文献
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本文详细介绍了技术质量部对用户厂家反映我公司25FS管莫尔条纹的问题进行的深入探究,发现其产生的三大主要物理原因,并作了适当的数学说明,并提出了相应的对策. 相似文献
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通信网建立时间同步网的方案探讨 总被引:1,自引:0,他引:1
从通信网体系结构入手,分析通信网层次结构与时延的关系.在对SDH网络层次结构分析的基础上,确定使用SOH中的MSOH来传递时间信号,以减小位置误差对时间不确定性的影响. 相似文献
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The use of a 20-kHz probe-type sonicator irradiating downward in a 500 mL vessel was optimized for the enhancement of the sonochemical activity in terms of the geometric and operational factors. These factors included the probe immersion depth (the vertical position of the probe), input power, height of the liquid from the bottom, horizontal position of the probe, and thickness of bottom plate The sonochemical oxidation reactions were investigated both quantitatively and qualitatively using calorimetry, KI dosimetry, and luminol (Sonochemiluminescence, SCL) techniques. The sonochemical activity was very positively affected by the vertical boundaries. The highest sonochemical activity was obtained when the probe was placed close to the bottom of the vessel (immersion depth of 60 mm), with a high input power (input power of 75%), and optimal liquid height condition (liquid height of 70 mm). The SCL image analysis showed that the cavitational activity zone gradually expanded around the probe body and changed into a circular shape as the experimental conditions were optimized, and consequently the sonochemical activity increased. The formation of a large bright circular-shaped activity zone could be attributed to the strong reflections of the ultrasound firstly, at the vessel bottom and secondly, at the liquid surface. On the other hand, the cavitational activity zone and the sonochemical activity were negatively affected by the horizontal boundaries when the probe was placed close to the side wall of the vessel. In addition, it was found that the sonochemical activity was also significantly affected by the thickness of the support plate owing to the reflection and transmission of the ultrasound at the boundary between the liquid and the solid media. 相似文献
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矿山开采中产生的固体废弃物和废液会使矿区土壤中富集重金属元素,进而影响矿区内的农作物生长。选择重庆市万盛区矿区作为研究区,采集红薯和南瓜的实测高光谱数据和土壤样本的重金属含量数据。通过对土壤重金属含量和农作物的红边位置偏移进行相关分析,发现不同土壤重金属含量对研究区内主要农作物的影响是不同的。可以看出,在研究区内的两种主要农作物中,红薯对矿区土壤中的重金属Cr、Mn和Cd比较敏感,而南瓜则对以上三种土壤重金属具有一定的吸收和抵抗作用。该结果可以为万盛区矿区内农作物种植的选择提供理论依据。 相似文献