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本文描述了用于中能重离子实验研究的由两维位置灵敏雪崩室和纵向电场电离室构成的组合式充气探测器的结构、工作原理和调试结果。其灵敏面积为２０ｃｍ×２０ｃｍ。在流动的正庚烷和异丁烯气体中，对￣（２５２）Ｃｆ裂变源，得到两维位置分辨为ΔＸ＝ΔＹ＝４ｍｍ，典型时间分辨为Δｔ＝８８Ｏｐｓ，并得到好的能量分辨

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模式标本是最重要的植物标本,是确定植物学名的依据,是植物分类学家从事植物系统分类研究必不可少的科学材料,也是开展专科专属研究、编写国家或地方植物志、进行植物区系调查研究、开发利用和保护植物资源的重要基本资料。但模式标本的人为和自然毁损难以避免,模式标本及其标签信息的数字化使得模式标本的形态、地理分布、采集等主要信息得到最大限度的永久保存,可以极大地方便模式标本信息的共享,可以为科学研究人员或相关人员提供植物形态、地理分布、历史变迁等多方面的信息。本文以中国科学院植物研究所国家植物标本馆维管束植物模式标本数字化建设为例,详细介绍了规范化整理模式标本的方法、模式标本数字化的操作流程,并通过大量实例介绍了模式标本考订的过程、常见问题的处理方法等,以期为其他单位开展模式标本数字化建设提供经验

Prediction of Energy Resolution in the JUNO Experiment

International audienceThis paper presents the energy resolution study in the JUNO experiment, incorporating the latest knowledge acquired during the detector construction phase. The determination of neutrino mass ordering in JUNO requires an exceptional energy resolution better than 3% at 1 MeV. To achieve this ambitious goal, significant efforts have been undertaken in the design and production of the key components of the JUNO detector. Various factors affecting the detection of inverse beta decay signals have an impact on the energy resolution, extending beyond the statistical fluctuations of the detected number of photons, such as the properties of liquid scintillator, performance of photomultiplier tubes, and the energy reconstruction algorithm. To account for these effects, a full JUNO simulation and reconstruction approach is employed. This enables the modeling of all relevant effects and the evaluation of associated inputs to accurately estimate the energy resolution. The study reveals an energy resolution of 2.95% at 1 MeV. Furthermore, the study assesses the contribution of major effects to the overall energy resolution budget. This analysis serves as a reference for interpreting future measurements of energy resolution during JUNO data taking. Moreover, it provides a guideline in comprehending the energy resolution characteristics of liquid scintillator-based detectors