Effect of Precondition on Porous Silicon Formation

本工作初步探讨了开路电位下对硅片进行预处理时多孔硅的形成过程 .电化学极化实验、扫描电镜和拉曼谱学的研究表明 ,预处理可以加速硅 /溶液界面上的化学或电化学反应 ,从而加快多孔硅的生长过程 ,最终导致光致发光的光谱红移 .多孔硅的厚度随预处理时间的增长而减小In this work, effect of precondition on porous silicon formation was investigated by performing electrochemical polarization measurements. The surface morphologies and optical properties of the samples were also studied by scanning electron microscopy (SEM) and Raman spectrometer. It was demonstrated that precondition enhanced the chemical/electrochemical reactions occurred at Si/solution interface and the growth of porous silicon, which ultimately resulted in a red shift in photoluminescence. However, the thickness of porous silicon decreased with the increase of precondition time. More broad bands were observed with prolonged precondition.作者联系地址：厦门大学化学系固体表面物理化学国家重点实验室,厦门大学化学系固体表面物理化学国家重点实验室 福建厦门361005 ,福建厦门361005Author's Address: Dept.of Chem., State Key Lab. for Phys. Chem. of Solid Surfaces, Xiamen Univ., Xiamen 361005,Chin

预处理对多孔硅形成过程的影响

【Abstract】In this work, effect of precondition on porous silicon formation was investigated by performing electrochemical polarization measurements. The surface morphologies and optical properties of the samples were also studied by scanning electron microscopy (SEM) and Raman spectrometer. It was demonstrated that precondition enhanced the chemical/electrochemical reactions occurred at Si/solution interface and the growth of porous silicon, which ultimately resulted in a red shift in photoluminescence. However, the thickness of porous silicon decreased with the increase of precondition time. More broad bands were observed with prolonged precondition.【中文摘要】本工作初步探讨了开路电位下对硅片进行预处理时多孔硅的形成过程 .电化学极化实验、扫描电镜和拉曼谱学的研究表明 ,预处理可以加速硅 /溶液界面上的化学或电化学反应 ,从而加快多孔硅的生长过程 ,最终导致光致发光的光谱红移 .多孔硅的厚度随预处理时间的增长而减

CaTi_(0.9)Li_(0.1)O_(3-δ)晶格中氧空位与选择性活性氧物种的TGA表征

用常规 Ｔ Ｇ Ａ（程序升温热重分析）法间接表征了催化剂 Ｃａ Ｔｉ０．９ Ｌｉ０．１ Ｏ３δ晶格中的氧空位，关联了氧空位、可活动氧量与催化剂的乙烷氧化脱氢（ Ｏ Ｄ Ｈ Ｅ）反应的催化性能，提出了乙烷在该类催化剂上氧化脱氢的选择性氧物种为 ８７３～１０２３ Ｋ 的温度范围内脱附的所谓可活动氧（ Ｏ－ ， Ｏ２－ ， Ｏ２－２ 简写为 Ｏδ）．利用 Ｏ２ Ｔ Ｐ Ｄ Ｍ Ｓ鉴定了 Ｔ Ｇ Ａ 结果，证明该法简便、实用、可靠

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

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

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