Measurement and Evaluation of Optical Surface after Precision Grinding

随着光学技术的发展，各种精密光学元件被广泛地应用于工农业生产，国防军事建设，航空航天科技等。为保证元件的加工精度，检测技术已成为先进光学元件制造的关键。合理的检测方法对评价元件表面特性以及指导元件的精密加工有着很大的帮助。 本文根据精密磨削加工的要求，从宏观角度对光学元件的表面形状进行检测；从微观角度对元件的表面粗糙度、微形貌等表面质量进行检测；以及对元件的亚表面损伤进行检测，从而为加工提供指导思想，实现高精度、高效率、低缺陷的磨削加工。本文具体研究内容如下： 1.设计了一套光学元件面形精度的在位检测系统，包括硬件系统的搭建和软件系统的开发，并对检测轨迹进行了规划，分析了不同检测路径的优缺...With the development of optical design and manufacturing technology, more and more optical components have been widely used in industrial and agricultural production, national defense, space navigation and so on. Because of the requirement of the accuracy, the measuring technology has become a key point of the manufacture of optical components. The reasonable measuring method is paling an importan...学位：工学硕士院系专业：物理与机电工程学院机电工程系_机械电子工程学号：1992007115113

输电塔挂线角钢节点理论计算方法研究

结合特高压工程数据对中冰区和重冰区输电塔典型挂线角钢节点在控制工况作用下的受力特点进行了数值模拟研究。研究结果表明：悬垂塔挂线角钢节点的变形受挂点垂直荷载控制，耐张塔挂点变形受挂点张力荷载控制，挂点螺栓主要受拉控制。根据数值模拟结果，结合传统的多排螺栓节点计算方法，量化了挂线角钢与螺栓群间的刚度差异，从应力-应变层面推导了一套考虑挂线角钢和螺栓相对抗弯刚度比影响的螺栓群理论计算方法，计算方法能够较好地反映挂点螺栓群布置形式和荷载作用形式对螺栓群受力中和轴位置的影响，计算结果与数值模拟结果吻合良好，精度较传统多排螺栓节点计算方法有较大的提高，可以用于指导工程实践，对输电塔结构设计的发展具有重要意义

庚型肝炎病毒合并/重叠其他肝炎病毒感染状况调查

目的: 了解庚型肝炎病毒(HGV)合并/重叠其他肝炎病毒感染状况。方法: 分别对 497 例不同病原的病毒性肝 炎患者进行 HGV RNA (RT PCR)检测, 对其中 180 例患者进行抗-HGV( ELISA)检测。结果 : ①HGV 在各型病毒性肝炎患者 中总的合并/重叠感染率为 7. 8%( 39/497)。 ②HGV 合并/重叠感染丙型肝炎病毒感染率为 18. 9%( 10/53) , 高于其他肝炎病 毒的合并/重叠感染率, P 0. 05)。 ⑤抗-HGV 的检出率为 12. 8%( 23/180) , 但其中仅有 21. 7%( 5/23)同时为 HGV RNA 阳性。结论:①输血是传播 HGV 的主 要途径之一,但 HGV 也可经非输血途径传播。 ②HGV 致病性可能较弱。 ③抗-HGV 阳性并不一定代表 HGV 病毒复制

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

JUNO Sensitivity on Proton Decay p→νˉK+p\to \bar\nu K^+ Searches

The Jiangmen Underground Neutrino Observatory (JUNO) is a large liquid scintillator detector designed to explore many topics in fundamental physics. In this paper, the potential on searching for proton decay in $p\to \bar\nu K^+$ mode with JUNO is investigated.The kaon and its decay particles feature a clear three-fold coincidence signature that results in a high efficiency for identification. Moreover, the excellent energy resolution of JUNO permits to suppress the sizable background caused by other delayed signals. Based on these advantages, the detection efficiency for the proton decay via $p\to \bar\nu K^+$ is 36.9% with a background level of 0.2 events after 10 years of data taking. The estimated sensitivity based on 200 kton-years exposure is $9.6 \times 10^{33}$ years, competitive with the current best limits on the proton lifetime in this channel

JUNO sensitivity on proton decay p → ν K + searches*

The Jiangmen Underground Neutrino Observatory (JUNO) is a large liquid scintillator detector designed to explore many topics in fundamental physics. In this study, the potential of searching for proton decay in the $p\to \bar{\nu} K^+$ mode with JUNO is investigated. The kaon and its decay particles feature a clear three-fold coincidence signature that results in a high efficiency for identification. Moreover, the excellent energy resolution of JUNO permits suppression of the sizable background caused by other delayed signals. Based on these advantages, the detection efficiency for the proton decay via $p\to \bar{\nu} K^+$ is 36.9% ± 4.9% with a background level of $0.2\pm 0.05({\rm syst})\pm$$0.2({\rm stat})$ events after 10 years of data collection. The estimated sensitivity based on 200 kton-years of exposure is $9.6 \times 10^{33}$ years, which is competitive with the current best limits on the proton lifetime in this channel and complements the use of different detection technologies

Measurement of integrated luminosity of data collected at 3.773 GeV by BESIII from 2021 to 2024

We present a measurement of the integrated luminosity e+e- of collision data collected by the BESIII detector at the BEPCII collider at a center-of-mass energy of Ecm = 3.773 GeV. The integrated luminosities of the datasets taken from December 2021 to June 2022, from November 2022 to June 2023, and from October 2023 to February 2024 were determined to be 4.995±0.019 fb-1, 8.157±0.031 fb-1, and 4.191±0.016 fb-1, respectively, by analyzing large angle Bhabha scattering events. The uncertainties are dominated by systematic effects, and the statistical uncertainties are negligible. Our results provide essential input for future analyses and precision measurements