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关键词： 实验教学   原子吸收光谱实验   数据处理  

摘要： 原子吸收光谱(AAS)实验是仪器分析和工科分析化学教学中必开设的实验课.常规开设的AAS实验包括用标准曲线(标准加入)法测定组成简单(复杂)样品中的金属离子.不管使用哪一种方法都需要待测元素标准系列溶液的配制、其吸光度的测定和实验数据的处理.AAS实验目的是让学生掌握AAS仪的使用方法、提高实验技能和处理实验数据的能力,同时密切结合课堂教学,提高教学效果.一般因实验数据处理由仪器工作站完成,既存在学生对数据处理方法理解不透,又存在教师对学生操作技能和实验结果的评价缺乏数据支撑等问题.在AAS实验教学中,尝试引入偏差计算概念,让学生独立处理AAS实验数据,掌握实验数据的简便处理方法,既有利于学生独立处理实验数据和巩固理论课中的相关知识点,又有利于教师评价AAS实验结果.

摘要： The KM3NeT collaboration is constructing two water-Cherenkov neutrino detectors in the Mediterranean sea. While one of the detectors is optimized for astrophysical research, the other is optimized for neutrino oscillations research. The latter detector is called ORCA and its main goals are to unravel the neutrino mass ordering and put world-leading constraints on the measurement of the sin 2 θ 23 and?∆m 2 31?? oscillation parameters. Although the detector is still under construction, with only 18 of the total 115 planned detection units deployed, it is already collecting data that can be used to perform neutrino oscillation research. To this end, the MONA software package was developed to model the expected event distributions as a function of the oscillation parameters and the observables, which are the reconstructed energy and direction of the neutrino. This thesis presents several improvements that were made to the model in the MONA software package, mostly concerning the usage of MC event weights and the implementation of nuisance parameters. In addition, an analysis of neutrino oscillations with 510 days of data collected by six detection units of the ORCA detector is presented using the improved model. Although this dataset does not have sufficient statistics to be sensitive to the neutrino mass ordering with relevant significance, the oscillation parameters are measured to be sin 2 θ 23 = 0.513 +0.054 −0.055 (stat) ±0.005 (sys) and?∆m 2 31?? = 2.16 +0.37 −0.15 (stat) ±0.28 (sys) [10 −3 eV 2 ]. The systematics involved in this measurement are also investigated in this thesis.

摘要： 近日,华北地区持续高温,河北涞源1000 千伏岳定双回特高压线路接续金具发现安全隐患,国家电网出动直升飞机,首次采用X射线检测作业,耗时 50分钟.在确保输电线路不停电的状态下,完成了对线路隐患点的检修作业任务,成功排除了隐患,有效保障了迎峰度夏期间京津冀地区电力供应.

摘要： Gunpowder is an ancient multipurpose invention from 9$^{th}$ century in China. The chemical composition and physical structure of gunpowder have been developed for centuries to fulfill many purposes which lead into the development of smokeless powder or propellants. Knowledge about the chemistry surrounding propellant is vastly studied and known but precise study of the interior structure of individual propellant grains are lacking. This study validates X-ray microtomography as a method to analyse the inner physical structures of propellant grains from 18 different batches. I measured two grains from each batch. My focus of interest was on interior material domain identification, their sizes, porosity, pore sizes and the correlation of these with the recipe of the propellant. To aid my analysis I used a Python script and batch specific recipes for almost all of the batches provided by Nammo Vihtavuori Oy. Particles identified from the images are nitrocellulose, potassium bitartrate, potassium sulfate, surface finishing compound and two metals: tin and bismuth. Identified components do not change their original grain like shape while inside propellant and their size is also preserved. However, variations inside the batches are high, resulting in different sized particles and pores in varying locations for each grain. Potassium nitrate salt had the only notable correlation to the inner structure of propellant grains: the more there was salt the higher the porosity and thinner the walls between the pores are. Unfortunately, large variations in the atomic number of component elements introduced artifacts into the images, and high variations between grains prevented me from gathering statistically relevant data. Nevertheless, imaging of propellant with X-ray tomography (X-CT) has proven useful giving lots of previously unknown information of the physical structure of propellant grains and their composition, which can be used to develop new improvements to propellant. Met

标准号: GB/T 42676-2023

摘要： 本文件描述了利用X射线衍射仪测试半导体材料双晶摇摆曲线半高宽，进而评价半导体单晶晶体质量的方法。
本文件适用于碳化硅、金刚石、氧化镓等单晶材料晶体质量的测试，硅、砷化镓、磷化铟等半导体材料晶体质量的测试也可参照本文件执行。

标准号: GB/T 6730.87-2023

摘要： 本文件规定了采用波长色散X射线荧光光谱法（钴内标法）测定全铁、硅、铝、钙、镁、锰、钛、钒、磷、铜、铅、铬、锌、砷、钾和硫含量的方法。
本文件适用于铁矿石、铁精矿、烧结矿及球团矿中下列各元素的测定，测定范围见表1。
 

标准号: GB/T 6150.10-2023

摘要： 本文件规定了钨精矿中铅含量的测定方法。
本文件适用于钨精矿中铅含量的测定，包含两个方法（方法一：氢化物发生原子荧光光谱法；方法 二：火焰原子吸收光谱法）。方法一测定范围（质量分数）:0.0010%~0.30%；方法二测定范围（质量分 数）:0.10%~0.50%。测定范围重叠部分以方法二为仲裁方法。