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Recovery of saturated signal waveform acquired from high-energy particles with artificial neural networks

Nuclear Science and Techniques 2019年第10期30卷 30-39页

作者： Yu Liu jing-jun zhu Neil Roberts Ke-Ming Chen Yu-Lu Yan Shuang-Rong Mo Peng Gu Hao-Yang Xing School of Physical Science and Technology Sichuan UniversityChengdu 610064China Key Laboratory of Radiation Physics and Technology of Ministry of Education Institute of Nuclear Science and TechnologySichuan UniversityChengdu 610065China Edinburgh Imaging School of Clinical SciencesUniversity of EdinburghEdinburghUK

Artificial neural networks(ANNs)are a core component of artificial intelligence and are frequently used in machine *** this report,we investigate the use of ANNs to recover the saturated signals acquired in highenergy particle and nuclear physics *** inherent properties of the detector and hardware imply that particles with relatively high energies probably often generate saturated ***,these saturated signals are discarded during data processing,and therefore,some useful information is ***,it is worth restoring the saturated signals to their normal *** mapping from a saturated signal waveform to a normal signal waveform constitutes a regression *** that the scintillator and collection usually do not form a linear system,typical regression methods such as multi-parameter fitting are not immediately *** important advantage of ANNs is their capability to process nonlinear regression *** recover the saturated signal,three typical ANNs were tested including backpropagation(BP),simple recurrent(Elman),and generalized radial basis function(GRBF)neural networks(NNs).They represent a basic network structure,a network structure with feedback,and a network structure with a kernel function,*** saturated waveforms were produced mainly by the environmental gamma in a liquid scintillation detector for the China Dark Matter Detection Experiment(CDEX).The training and test data sets consisted of 6000 and 3000 recordings of background radiation,respectively,in which saturation was simulated by truncating each waveform at 40%of the maximum *** results show that the GBRF-NN performed best as measured using a Chi-squared test to compare the original and reconstructed signals in the region in which saturation was simulated.A comparison of the original and reconstructed signals in this region shows that the GBRF neural network produced the best *** ANN demonstrates a powerful efficacy

关键词： Saturated signals Artificial neural networks(ANNs) Recovery of signal waveform Generalized radial basis function Backpropagation neural network Elman neural network

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A simulation study of a windowless gas-stripping room in an E//B neutral particle analyzer

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Nuclear Science and Techniques 2021年第7期32卷 22-30页

作者： Yuan Luo Wei-Ping Lin Pei-Pei Ren Guo-Feng Qu jing-jun zhu Xing-Quan Liu Xiao-Bing Luo zhu An Roy Wada Lin-Ge Zang Yu-Fan Qu Zhong-Bing Shi Key Laboratory of Radiation Physics and Technology of the Ministry of Education Institute of Nuclear Science and TechnologySichuan UniversityChengdu 610064China Cyclotron Institute Texas A&M UniversityCollege StationTX 77843USA School of Physics Henan Normal UniversityXinxiang 453007China Southwestern Institute of Physics Chengdu 610064China

The neutral particle analyzer(NPA)is one of the crucial diagnostic devices in a Tokamak *** stripping unit is one of the main parts of the NPA.A windowless gas-stripping room with two differential pipes has been constructed in a parallel electric and magnetic fields(E//B)*** pressure distributions in the stripping chamber are simulated by ANSYS Fluent together with MolFlow+.Based on the pressure distributions obtained from the simulation,the stripping efficiency of the E//B NPA is studied using *** reaction physics is modified to track the charge state of each particle in a cross-section-based method in *** transmission rates(R)and stripping efficiencies f_(+1)are examined for particle energies ranging from 20 to 200 keV with the input pressure(P_(0)),ranging from 20 to 400 *** to the combined global efficiency,R×f_(+1),P_(0)=240 Pa is obtained as the optimum pressure for the maximum global efficiency in the incident energy range investigated.

关键词： Neutral particle analyzer Windowless gas-stripping chamber Stripping efficiency Ansys Fluent MolFlow+ GEANT4

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Study on cosmogenic radioactive production in germanium as a background for future rare event search experiments

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Nuclear Science and Techniques 2020年第6期31卷 22-29页

作者： Yu-Lu Yan Wei-Xin Zhong Shin-Ted Lin jing-jun zhu Chen-Kai Qiao Lei Zhang Yu Liu Qian Yue Hao-Yang Xing Shu-Kui Liu College of Physics Sichuan UniversityChengdu 610064China School of Physics Nankai UniversityTianjin 30071China Institute of Nuclear Science and Technology Sichuan UniversityChengdu 610065China Department of Engineering Physics Tsinghua UniversityBeijing 100084China

Rare event search experiments are one of the most important topics in the field of fundamental physics,and high-purity germanium(HPGe)detectors with an ultralow radioactive background are frequently used for such ***,cosmogenic activation contaminates germanium crystals during transport and *** this study,we investigated the movable shielding containers of HPGe crystals using Geant4 and CRY Monte Carlo *** production rates of 68Ge,65Zn,60Co,55Fe,and 3H were obtained individually for different types of cosmic *** validity of the simulation was confirmed through a comparison with the available experimental *** on this simulation,we found that the interactions induced by neutrons contribute to approximately 90%of the production rate of cosmogenic *** addition,by adding an optimized shielding structure,the production rates of cosmogenic radionuclides are reduced by about one order of *** results show that it is feasible to use a shielding container to reduce the cosmogenic radioactivity produced during the transport and storage of high-purity germanium on the ground.

关键词： High-purity germanium Shielding structure Geant4 Transportation

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Identification of anomalous fast bulk events in a p-type point-contact germanium detector

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Nuclear Science and Techniques 2022年第5期33卷 53-67页

作者： Ren-Ming-Jie Li Shu-Kui Liu Shin-Ted Lin Li-Tao Yang Qian Yue Chang-Hao Fang Hai-Tao Jia Xi Jiang Qian-Yun Li Yu Liu Yu-Lu Yan Kang-Kang Zhao Lei Zhang Chang-Jian Tang Hao-Yang Xing jing-jun zhu College of Physics Sichuan UniversityChengdu 610065China Key Laboratory of Particle and Radiation Imaging(Ministry of Education)and Department of Engineering Physics Tsinghua UniversityBeijing 100084China

The ultralow detection threshold,ultralow intrinsic background,and excellent energy resolution of ptype point-contact germanium detectors are important for rare-event searches,in particular for the detection of direct dark matter interactions,coherent elastic neutrino-nucleus scattering,and neutrinoless double beta *** bulk events with an extremely fast rise time are observed in the CDEX-1B *** report a method of extracting fast bulk events from bulk events using a pulse shape simulation and reconstructed source experiment *** data and the distribution of X-rays generated by intrinsic radioactivity verified that the fast bulk experienced a single hit near the passivation *** performance of this germanium detector indicates that it is capable of single-hit bulk spatial resolution and thus provides a background removal technique.

关键词： p-type point-contact germanium detector Dark matter Pulse shape analysis Anomalous fast bulk events

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Experimental study on the gas-stripping chamber of an E//B neutral particle analyzer

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Nuclear Science and Techniques 2024年第11期35卷 98-107页

作者： Long Ma De-Hao Xie Yan-Xi Wang Shuo Wang Ji-Feng Han Wei-Ping Lin Jian-Li Liu Xing-Quan Liu Yu-Guo Liu Xiao-Bing Luo Yuan Luo Guo-Feng Qu Yu-Fan Qu Pei-Pei Ren Roy Wada Lin-Ge Zang jing-jun zhu Key Laboratory of Radiation Physics and Technology of the Ministry of Education Institute of Nuclear Science and TechnologySichuan UniversityChengdu 610064China Institute of Modern Physics Chinese Academy of SciencesLanzhou 730000China Southwestern Institute of Physics Chengdu 610218China Cyclotron Institute Texas A&M UniversityCollege StationTX 77843USA

Stripping units take a key role in the neutral particle analyzer(NPA).A renovated gas-stripping unit was constructed for the newly designed E//B *** H_(2)as the working gas,we measured the gas inlet pressure(P_(0))and vacuum chamber pressure(P_(3)).The pressure distribution inside the gas-stripping room was calculated with Ansys Fluent,using the measured P_(0)and P_(3)as boundary *** stripping efficiency of the stripping unit was then simulated utilizing the Geant4 Monte Carlo code for the H and D *** pressure P_(0)=40 Pa,which is one-sixth of what found in the previous design and corresponds to a thickness of 1.27×10^(17)atoms∕cm^(2),was obtained as the optimum working pressure for the upgraded stripping *** 50 kV electron cyclotron resonance(ECR)ion source platform was designed and constructed for E//B NPA calibration,and its performance has been *** the ECR ion source platform,we measured the efficiency of the stripping unit through an inverse experiment with proton *** compared the current ratios of measurements with and without H_(2)gas to Geant4 simulation *** found adequate agreement between the overall trends of the experiment and the *** significant deviation for incident energies below 20 keV may result from the scattering effects of low-energy protons,leading to reduced accuracy in single-scattering physics in Geant4 *** the scattering corrections observed in the reverse experiments obtains more accurate stripping efficiencies for H and D atoms in the energy range of 20–200 keV and the global efficiency with the maximum values of 95.0%for H atoms and 78.9%for D atoms at 200 keV.

关键词： NPA Gas-stripping ECR ion source Stripping efficiency Geant4

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High‑accuracy measurement of Compton scattering in germanium for dark matter searches

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Nuclear Science and Techniques 2022年第12期33卷 75-87页

作者： Hai‑Tao Jia Shin‑Ted Lin Shu‑Kui Liu Hsin‑Chang Chi Muhammed Deniz Chang‑Hao Fang Peng Gu Xi Jiang Yi‑Ke Shu Qian‑Yun Li Yu Liu Ren‑Ming‑Jie Li Chen‑Kai Qiao Chang‑Jian Tang Henry Tsz‑King Wong Hao‑Yang Xing Li‑Tao Yang Qian Yue Yu‑Lu Yan Kang‑Kang Zhao jing‑jun zhu College of Physics Sichuan University610065 ChengduChina Department of Physics National Dong Hwa University97401 ShoufengHualienChina Department of Physics Dokuz Eylül University35160 BucaİzmirTurkey Institute of Physics Academia Sinica11529 TaipeiChina Key Laboratory of Particle and Radiation Imaging(Ministry of Education)and Department of Engineering Physics Tsinghua University100084 BeijingChina Institute of Nuclear Science and Technology Sichuan University610065 ChengduChina

Compton scattering with bound electrons contributes to a significant atomic effect in low-momentum transfer,yielding background structures in direct light dark matter searches as well as low-energy rare event *** report the measurement of Compton scattering in low-momentum transfer by implementing a 10-g germanium detector bombarded by a^(137)Cs source with a radioactivity of 8.7 mCi and a scatter photon captured by a cylindrical NaI(Tl)detector.A fully relativistic impulse approximation combined with multi-configuration Dirac–Fock wavefunctions was evaluated,and the scattering function of Geant4 software was replaced by our calculation *** measurements show that the Livermore model with the modified scattering function in Geant4 is in good agreement with the experimental *** is also revealed that atomic many-body effects significantly influence Compton scattering for low-momentum transfer(sub-keV energy transfer).

关键词： Compton scattering experiment Germanium detector Atomic many-body effects Geant4 Dark matter

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Structural and microwave absorption properties of CoFe_(2)O_(4)/residual carbon composites

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 221-232页

作者： Yuanchun Zhang Shengtao Gao Xingzhao Zhang Dacheng Ma Chuanlei zhu jun He Joint National-Local Engineering Research Centre for Safe and Precise Coal Mining Anhui University of Science and TechnologyHuainan 232001China School of Chemical and Blasting Engineering Anhui University of Science and TechnologyHuainan 232001China

Electromagnetic interference,which necessitates the rapid advancement of substances with exceptional capabilities for bsorbing electromagnetic waves,is of urgent concern in contemporary *** this work,CoFe_(2)O_(4)/residual carbon from coal gasification fine slag(CFO/RC)composites were created using a novel hydrothermal *** mechanisms for microwave absorption,including conductive loss,natural resonance,interfacial dipole polarization,and magnetic flux loss,are involved in these ***,compared with pure residual carbon materials,this composite offers superior capabilities in microwave *** 7.76GHz,the CFO/RC-2 composite achieves an impressive minimum reflection loss(RL_(min))of-43.99 dB with a thickness of 2.44 ***,CFO/RC-3 demonstrates an effective absorption bandwidth(EAB)of up to 4.16 GHz,accompanied by a thickness of *** study revealed the remarkable capability of the composite to diminish electromagnetic waves,providing a new generation method for microwave absorbing materials of superior quality.

关键词： coal gasification slag residual carbon hydrothermal method microwave absorption CoFe_(2)O_(4)

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Dip2a regulates stress susceptibility in the basolateral amygdala

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Neural Regeneration Research 2025年第6期20卷 1735-1748页

作者： jing Li Zixuan He Weitai Chai Meng Tian Huali Yu Xiaoxiao He Xiaojuan zhu Key Laboratory of Molecular Epigenetics Ministry of Education Institute of Genetics and CytologyNortheast Normal UniversityChangchunJilin ProvinceChina

Dysregulation of neurotransmitter metabolism in the central nervous system contributes to mood disorders such as depression, anxiety, and post–traumatic stress disorder. Monoamines and amino acids are important types of neurotransmitters. Our previous results have shown that disco-interacting protein 2 homolog A(Dip2a) knockout mice exhibit brain development disorders and abnormal amino acid metabolism in serum. This suggests that DIP2A is involved in the metabolism of amino acid–associated neurotransmitters. Therefore, we performed targeted neurotransmitter metabolomics analysis and found that Dip2a deficiency caused abnormal metabolism of tryptophan and thyroxine in the basolateral amygdala and medial prefrontal cortex. In addition, acute restraint stress induced a decrease in 5-hydroxytryptamine in the basolateral amygdala. Additionally, Dip2a was abundantly expressed in excitatory neurons of the basolateral amygdala, and deletion of Dip2a in these neurons resulted in hopelessness-like behavior in the tail suspension test. Altogether, these findings demonstrate that DIP2A in the basolateral amygdala may be involved in the regulation of stress susceptibility. This provides critical evidence implicating a role of DIP2A in affective disorders.

关键词： 5-hydroxytryptamine acute restraint stress basolateral amygdala CaMKII neurons DIP2A metabolomics neurotransmitters principal component analysis stress susceptibility tryptophan

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高龄初产妇妊娠结局探讨

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临床合理用药杂志 2010年第16期3卷 38-39页

作者：敬竹筠四川省双流县妇幼保健院 610200

目的探讨高龄初产对妊娠结局的影响,为临床咨询和处理提供依据。方法选择63例高龄初产妇作为研究组,另选同期分娩的适龄产妇109例作为对照组,比较2组妊娠合并症、分娩并发症、孕产妇分娩方式及新生儿情况。结果研究组妊娠高血压综合征... 详细信息

目的探讨高龄初产对妊娠结局的影响,为临床咨询和处理提供依据。方法选择63例高龄初产妇作为研究组,另选同期分娩的适龄产妇109例作为对照组,比较2组妊娠合并症、分娩并发症、孕产妇分娩方式及新生儿情况。结果研究组妊娠高血压综合征、糖尿病、胎儿窘迫、产程异常及产后出血等发生率高于对照组,差异均有统计学意义(P<0.05或P<0.01)。研究组发生新生儿异常17例(27.0%),对照组9例(8.3%);研究组剖宫产33例(52.4%),顺产25例(39.7%),对照组剖宫产17例(15.6%),顺产84例(77.1%),2组比较差异均有统计学意义(P<0.05)。结论高龄初产妇妊娠、分娩的风险较高,应该尽量避免高龄妊娠。做好产前检查和围生期保健以确保高龄产妇分娩时母婴的安全。

关键词：高龄妊娠妊娠结局妊娠合并症剖宫产

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Zebrafish:a predictive model for assessing developmental toxicity and teratotoxicity of drugs

Zebrafish:a predictive model for assessing developmental tox...

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中国药理学会第十一次全国学术会议

作者： CHEN Ru-jia,zhu jun-jing,zhu Xiao-yu,ZHANG Yong,LI Chun-qi (1.Hunter Biotechnology,Inc.,Transfarland,Xiaoshan Economic & Technology Development Zone,Hangzhou 311231,China)

OBJECTIVE Conventional assessment of developmental toxicity and teratotoxicity in mammalian models is laborious and time *** the early 1980s,alternative methods for assessing developmental toxicity have been developed,including in vitro cell differentiation assays using either primary cell cultures or immortalized cell lines,the in vitro rodent whole embryo culture test and the in vivo frog embryo teratogenesis assay(FETAX).In vitro tests have been of limited value in predicting the effect of drugs on human embryonic and fetal *** of the in vivo FETAX assay include that xenopus do not have a characterized chemical metabolic pathway and they are insensitive to halogenated aromatic *** screening technologies is required to generate data directly for risk assessment or for prioritization of compounds for further testing in *** is emerging as an alternative vertebrate animal model for assessing toxicity and safty of compounds,in part due to its transpatency,rapid development, and simplicity of compound *** Zebrafish of the AB wild-type strain were reared under standard *** were collected from natural spawnings,staged according to established *** known mammalian-teratogenic compounds were as follows:bisphenol A,ethanol,lead nitrate,lithium chloride,tobacco leachate,caffeine and sudanⅠ.Three mammalian non-tera-totoxicity compounds were sucrose,saccharin and *** were exposed to three concentrations(LC,MNLCand 1/2 MN-LC) in each compound from 6 hpf to 120 hpf,30 zebrafish wree treated with each *** treatment,10 zebrafish from each group were randomly selected and images were acquired using a dissecting *** assessed the endpoints of evelop-mental toxicity and teratotoxicity at 120 *** All 7 known mammalian-teratogenic compounds induced evelopmental toxicity in *** major teratotoxicity were pericardial edema,head mal

关键词： zebrafish developmental toxicity teratotoxicity animal model

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