滚滑运动导致的滚动轴承磨损特性研究

滚滑运动是导致滚动轴承失效的一种特殊运动形式，采用仿真和试验相结合的方法，研究了滚动轴承在滚滑运动下的磨损特性。首先，应用Abaqus有限元软件建立滚滑状态下的滚动轴承有限元仿真模型，得到轴承的摩擦力动态响应。之后，通过滚滑磨损试验台得到轴承运动过程中的摩擦力数据，运用灰色关联分析法得知仿真数据与试验数据的关联度达到0.8以上，因此，仿真所得的摩擦力可作为判断轴承磨损状态变化的依据。在轴承磨损试验中，对润滑油进行颗粒度检测并观察记录了轴承内圈的表面形貌。结果表明，仿真所得摩擦力变化影响油液颗粒度、表面形貌的变化，油液中所含颗粒数目上升与内圈表面产生磨痕作为内圈所受摩擦力变化导致的磨损结果，正反馈于摩擦力，使其幅值不断增大，进一步加剧了轴承的磨损。仿真与试验相结合的方法为准确判断滚滑状态下轴承各点位置磨损特性提供了分析研究的基础

Determination of the number of ψ(3686) events taken at BESIII

The number of ψ(3686) events collected by the BESIII detector during the 2021 run period is determined to be (2259.3±11.1)×106 by counting inclusive ψ(3686) hadronic events. The uncertainty is systematic and the statistical uncertainty is negligible. Meanwhile, the numbers of ψ(3686) events collected during the 2009 and 2012 run periods are updated to be (107.7±0.6)×106 and (345.4±2.6)×106, respectively. Both numbers are consistent with the previous measurements within one standard deviation. The total number of ψ(3686) events in the three data samples is (2712.4±14.3)×10^

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