The Influence of Metallurgy process on Impurity Distribution and Electrical Properties of UMG-Si

硅是太阳电池的主要原料，其杂质的含量和分布直接影响太阳电池的发电效率和使用寿命。研究冶金工艺对高纯硅中杂质分布及电学性能的影响具有重要的意义。 本文以两种不同的冶金工艺对工业硅进行预处理，最后通过真空定向凝固制备多晶硅锭，分析和研究两铸锭的宏观形貌、微观结构特征，探讨两铸锭中主要杂质元素的分布规律，通过计算铸锭不同高度理论值和实测值来分析杂质去除机制，最后结合电学性能测试来讨论杂质和晶体学缺陷对铸锭电阻率、导电类型、少子寿命的影响。主要研究结果如下： 1、采用两种不同工艺（A：真空-造渣-酸洗、B：造渣-酸洗-真空）对工业硅进行预处理。最后结果表明：硼、磷杂质元素在A工艺的精炼下有一定程度...Silicon is the main raw material of the solar cell, its impurity content and distribution directly affects the electricity generation efficiency and service life of the solar cell. Study on the influence of metallurgy processes on impurity distribution and electrical properties of high-purity silicon are of great importance. In the present thesis, metallurgical grade silicon had been pretreat...学位：工学硕士院系专业：材料学院_材料学学号：2072010115009

Hydrothermal synthetic ZnAl_2O_4 and Humidity sensing properties research

以Al2(SO4)3和zn(nO3)2为原料,采用水热法合成铝酸锌微粉体,通过扫描电镜和Xrd分析发现znAl2O4晶型良好,粒径小,呈纤维状均匀分布;进一步研究湿敏特性,结果表明:测试频率对阻抗-相对湿度(rH)特性曲线影响较大,阻抗随频率的增加而迅速减小,10kHz时在33%~95%的范围内曲线的线性度好,在相同的湿度下,试样的电容随频率的增加而减小,在低频100Hz下,电容随相对湿度的升高而增大。A simple hydrothermal was developed to fabricate ZnAl2O4 micro powder with Al2(SO4)3 and Zn(NO3)2 as raw materials,through the scanning electron microscopy(SEM)and XRD analysis found that the particles have good crystal shapesmall size,fibrous evenly distributed;Further researching the humidity sensing properties,the results show that test frequency have big effect on impedance-relative humidity(RH)characteristic curve,impedance decreases as frequency increases,the good linearity of the curve of impedance versus relative humidity appears at the frequency of 10KHZ,the capacitance of the sensor decreases as frequency increases in the same humidity and at low measurement frequency 100HZ,the capacitance increases as RH increases

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

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