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In-beam gamma rays of CSNS Back-n characterized by black resonance filter

NUCLEAR SCIENCE AND TECHNIQUES 2024年第10期35卷 1-12页

作者： Wang, Jin-Cheng Ren, Jie Jiang, Wei Ruan, Xi-Chao Liu, Ying-Yi Yang, hao-Lan Xu, Kuo-zhi Pan, Xin-Yi Sun, Qi Bao, Jie Huang, Han-Xiong Bai, hao-Fan Bai, Jiang-Bo Cao, Ping Chen, Qi-Ping Chen, Yong-hao Duan, Wen-hao Fan, An-Chuan Fan, Rui-Rui Feng, Chang-Qing Gu, Min-hao Han, Chang-Cai Han, Zi-Jie He, Guo-Zhu He, Yong-Cheng Hong, Yang Hu, Yi-Wei Jiang, zhi-Jie Kang, Ling Lan, Chang-Lin Li, Bo Li, Feng Li, Qiang Li, Xiao Li, Yang Liu, Jie Liu, Rong Liu, Shu-Bin Liu, Yi-Na Luan, Guang-Yuan Ning, Chang-Jun Qiu, Yi-Jia Ren, Wen-Kai Ren, zhi-zhou Song, Zhao-Hui Sun, Kang Tan, zhi-Xin Tang, Jing-Yu Tang, Sheng-Da Wang, Li-Jiao Wang, Peng-Cheng Wang, Zhao-Hui Wen, Zhong-Wei Wu, Xiao-Guang Wu, Xuan Wu, Ze-Peng Xia, Cong Xie, Li-Kun Yi, Han Yu, Tao Yu, Yong-Ji Zhang, Guo-Hui Zhang, Hang-Chang Zhang, Qi-Wei Zhang, Xian-Peng Zhang, Yu-Liang Zhang, zhi-Yong Zhao, Mao-Yuan zhou, zhi-hao Zhu, Ke-Jun Zou, Chong China Inst Atom Energy Key Lab Nucl Data Beijing 102413 Peoples R China Chinese Acad Sci Inst High Energy Phys Beijing 100049 Peoples R China Spallat Neutron Source Sci Ctr Dongguan 523803 Peoples R China Chinese Acad Sci Inst High Energy Phys State Key Lab Particle Detect & Elect Beijing 100049 Peoples R China Univ Chinese Acad Sci Beijing 100049 Peoples R China Peking Univ Sch Phys State Key Lab Nucl Phys & Technol Beijing 100871 Peoples R China Fudan Univ Inst Modern Phys Shanghai 200433 Peoples R China Univ Sci & Technol China State Key Lab Particle Detect & Elect Hefei 230026 Peoples R China Univ Sci & Technol China Sch Nucl Sci & Technol Hefei 230026 Peoples R China Univ Sci & Technol China Dept Modern Phys Hefei 230026 Peoples R China China Acad Engn Phys Inst Nucl Phys & Chem Mianyang 621900 Peoples R China Univ Sci & Technol China USTC Archaeometry Lab Hefei 230026 Peoples R China Northwest Inst Nucl Technol Xian 710024 Peoples R China Lanzhou Univ Sch Nucl Sci & Technol Lanzhou 730000 Peoples R China Univ Sci & Technol China Inst Adv Technol Hefei 230027 Peoples R China

The back-streaming white-neutron beamline (Back-n) of the China Spallation Neutron Source is an essential neutron- research platform built for the study of nuclear data, neutron physics, and neutron applications. Many types of cross-sectional neutron-reaction measurements have been performed at Back-n since early 2018. These measurements have shown that a significant number of gamma rays can be transmitted to the experimental stations of Back-n along with the neutron beam. These gamma rays, commonly referred to as in-beam gamma rays, can induce a non-negligible experimental background in neutron-reaction measurements. Studying the characteristics of in-beam gamma rays is important for understanding the experimental background. However, measuring in-beam gamma rays is challenging because most gamma-ray detectors are sensitive to neutrons; thus, discriminating between neutron-induced signals and those from in-beam gamma rays is difficult. In this study, we propose the use of the black resonance filter method and a CeBr3 scintillation detector to measure the characteristics of the in-beam gamma rays of Back-n. Four types of black resonance filters, Ta-181, Co-59, Ag-nat, and Cd-nat, were used in this measurement. The time-of-flight (TOF) technique was used to select the detector signals remaining in the absorption region of the TOF spectra, which were mainly induced by in-beam gamma rays. The energy distribution and flux of the in-beam gamma rays of Back-n were determined by analyzing the deposited energy spectra of the CeBr3 scintillation detector and using Monte Carlo simulations. Based on the results of this study, the background contributions from in-beam gamma rays in neutron-reaction measurements at Back-n can be reasonably evaluated, which is beneficial for enhancing both the experimental methodology and data analysis.

关键词： In-beam gamma rays Back-n Black filter resonance technique In-beam gamma rays Back-n CeBr3 scintillator Black filter resonance technique C6D6 DETECTOR SYSTEM LINE

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Learnware:small models do big

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Science China(Information Sciences) 2024年第1期67卷 39-50页

作者： zhi-Hua zhou zhi-hao TAN National Key Laboratory for Novel Software Technology Nanjing University

There are complaints about current machine learning techniques such as the requirement of a huge amount of training data and proficient training skills,the difficulty of continual learning,the risk of catastrophic forgetting,and the leaking of data privacy/*** research efforts have been focusing on one of those concerned issues separately,paying less attention to the fact that most issues are entangled in *** prevailing big model paradigm,which has achieved impressive results in natural language processing and computer vision applications,has not yet addressed those issues,whereas becoming a serious source of carbon *** article offers an overview of the learnware paradigm,which attempts to enable users not to need to build machine learning models from scratch,with the hope of reusing small models to do things even beyond their original purposes,where the key ingredient is the specification which enables a trained model to be adequately identified to reuse according to the requirement of future users who know nothing about the model in advance.

关键词： artificial intelligence machine learning learnware

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数字经济对甘肃省高质量发展的赋能效应研究——基于产业结构升级视角

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兰州财经大学学报 2024年第4期40卷 106-114页

作者：王连田亚军周之浩兰州财经大学统计与数据科学学院甘肃兰州730020

数字经济作为新的经济形态,已成为推动高质量发展的重要引擎。基于2011—2020年甘肃省14个市(州)的面板数据,实证分析数字经济赋能甘肃省高质量发展的影响效应。研究发现:数字经济对甘肃省高质量发展具有显著促进作用,可以为甘肃省高质... 详细信息

数字经济作为新的经济形态,已成为推动高质量发展的重要引擎。基于2011—2020年甘肃省14个市(州)的面板数据,实证分析数字经济赋能甘肃省高质量发展的影响效应。研究发现:数字经济对甘肃省高质量发展具有显著促进作用,可以为甘肃省高质量发展提供新的动力支持;数字经济可以通过产业结构升级对高质量发展产生积极推动作用,其中产业结构高级化中介效应显著,产业结构合理化的中介效应不显著;数字经济对甘肃省高质量发展的赋能效应存在显著异质性,经济发展水平越高的地区数字经济的赋能效应越高。据此,为巩固和发展数字经济赋能甘肃省高质量发展的优势,从发挥数字经济红利、助推产业转型升级、加强对外开放等方面提出建议。

关键词：数字经济高质量发展产业结构升级中介效应分位数回归模型

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基于FA-LSTM的燃气轮机燃烧室故障演化趋势预估

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汽轮机技术 2024年第5期66卷 368-372,378页

作者：卿硕袁国凯吴伟秋傅颖林朝靖周之豪龙振华清洁高效透平动力装备全国重点实验室德阳618000 东方汽轮机有限公司德阳618000 哈尔滨工业大学能源科学与工程学院哈尔滨150001

燃气轮机高温部件的故障发生率高、隐蔽性强、破坏性大,且故障发生后维修成本高、维修难度大。研究一种故障演化趋势预估方法对于维修人员及时维修和制定维修决策具有重大意义。介绍了一种基于FA-LSTM的故障演化趋势预估方法,结合燃烧... 详细信息

燃气轮机高温部件的故障发生率高、隐蔽性强、破坏性大,且故障发生后维修成本高、维修难度大。研究一种故障演化趋势预估方法对于维修人员及时维修和制定维修决策具有重大意义。介绍了一种基于FA-LSTM的故障演化趋势预估方法,结合燃烧室退化机理采用因子分析法(FA)构建健康因子(HI)用于衡量燃机燃烧室的健康状态。利用长短时记忆神经网络(LSTM)特有的处理时间序列数据的能力,预测燃烧室故障演化趋势。以某型燃气轮机为研究对象,并将所提方法与其它6种传统机器学习方法对比,本方法的预测结果MAE和RMSE均最低,能实现准确的退化趋势预测,为短期维护提供有效依据。

关键词：燃气轮机故障演化趋势因子分析长短时记忆神经网络

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Beamline design for multipurpose muon beams at CSNS EMuS

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Nuclear Science and Techniques 2024年第5期35卷 1-12页

作者： Yang Hong Ying-Peng Song Lu-Ping zhou Jing-Yu Tang zhi-hao zhou Nikolaos Vassilopoulos Institute of High Energy Physics Chinese Academy of Sciences(CAS)Beijing 100049China Spallation Neutron Source Science Center Dongguan 523803China University of Chinese Academy of Sciences Beijing 100049China Radiotherapy Physics and Technology Center Cancer CenterWest China HospitalSichuan UniversityChengdu 610041China Xi’an Jiaotong University Health Science Center Xi’an 710049China Department of Radiation Oncology First Affiliated Hospital of Xi’an Jiaotong UniversityXi’an 710049China School of Nuclear Science and Technology University of Science and Technology of ChinaHefei 230027China

A new muon beam facility,called the Experimental Muon Source(EMuS),was proposed for construction at the China Spallation Neutron Source(CSNS).The design of the complex muon beamlines for the EMuS baseline scheme,which is based on superconducting solenoids,superferric dipoles and room-temperature magnets,is presented *** muon beams,including surface muons,decay muons and low energy muons,have been developed for multipurpose *** optics design and simulation results of the trunk beamline and branch beamlines are *** a proton beam power of 25 kW at a standalone target station that consists of a conical graphite target and high-field superconducting solenoids,the muon beam intensity in the trunk beamline varies from 10^(7)/s for surface muons to 10^(10)/s for high-momentum decay *** at the endstations,these values vary from 10^(5)/s for surface muons to 10^(8)/s for decay muons.

关键词： Surface muons Decay muons Muon beamline Superconducting solenoids Multi-channel electrostatic separator

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P-symmetric Subharmonic Solutions for Nonlinear Hamiltonian Systems

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Acta Mathematica Sinica,English Series 2024年第6期40卷 1388-1408页

作者： Duan zhi ZHANG zhi hao Zhao School of Mathematical Sciences Nankai UniversityTianjin 300071P.R.China

In this paper,we prove that for each positive k≡1 mod m there exists a P-symmetric kmτ-periodic solution xk for asymptotically linear mτ-periodic Hamiltonian systems,which are nonautonomous and endowed with a *** the P-symmetric Hamiltonian function is semi-positive,one can prove,under a new iteration inequality of the Maslov-type P-index,that xk_(1) and xk_(2) are geometrically distinct for k_(1)/k_(2)≥(2n+1)m+1;and xk_(1),xk_(2) are geometrically distinct for k_(1)/k_(2)≥m+1 provided xk_(1) is non-degenerate.

关键词： P-symmetric subharmonic Hamiltonian systems Maslov-type index theory iteration inequality asymptotically linear

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Measurement of the high energyγ-rays from heavy ion reactions usingČerenkov detector

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Nuclear Science and Techniques 2024年第2期35卷 123-130页

作者： Da-Wei Si Yan zhou Sheng Xiao zhi Qin Dong Guo Yu-hao Qin Yi-Jie Wang Bo-Yuan Zhang Bai-Ting Tian zhi-Gang Xiao Department of Physics Tsinghua UniversityBeijing 100084China

The energetic bremsstrahlung photons up to 100 MeV produced in heavy ion collisions can be used as a sensitive probe for short-range correlation in atomic nuclei. The energy of the γ-rays can be measured by collecting the Čerenkov light in the medium induced by the fast electrons generated in the Compton scattering or electromagnetic shower of the incident γray. Two types of detectors based on pure water and lead glass as sensitive materials were designed for this purpose. The γresponse and optical photon propagation in the detectors were simulated based on electromagnetic and optical processes in Geant4. The inherent energy resolutions of 0.022(4) + 0.51(2)∕E^(1/2)_(γ) for water and 0.0026(3) + 0.446(3)∕E^(1/2)_(γ) for lead glass were obtained. The geometry sizes of the lead glass and water were optimized to 30 cm × 30 cm × 30 cm and 60 cm × 60 cm ×120 cm, respectively, to detect high-energy γ-rays at 160 MeV. The Hough transform method was applied to reconstruct the direction of the incident γ-rays, providing the ability to experimentally distinguish the high-energy γ-rays produced in the reactions on the target from random background cosmic-ray muons.

关键词： Bremsstrahlungγ-rays Čerenkov Geant4 Energy resolution Direction reconstruction Hough transform

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Evolutionary dynamics of tax-based strong altruistic reward andpunishment in a public goods game

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Chinese Physics B 2024年第9期33卷 247-257页

作者： zhi-hao Yang Yan-Long Yang Mathematics and Statistics School Guizhou UniversityGuiyang 550025China

In public goods games, punishments and rewards have been shown to be effective mechanisms for maintaining individualcooperation. However, punishments and rewards are costly to incentivize cooperation. Therefore, the generation ofcostly penalties and rewards has been a complex problem in promoting the development of cooperation. In real society,specialized institutions exist to punish evil people or reward good people by collecting taxes. We propose a strong altruisticpunishment or reward strategy in the public goods game through this phenomenon. Through theoretical analysis and numericalcalculation, we can get that tax-based strong altruistic punishment (reward) has more evolutionary advantages thantraditional strong altruistic punishment (reward) in maintaining cooperation and tax-based strong altruistic reward leads toa higher level of cooperation than tax-based strong altruistic punishment.

关键词： evolutionary game theory strong altruism punishment reward

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Saponin Ⅰ from Shuitianqi(Rhizoma Schizocapasae Plantagineae) inhibits metastasis by negatively regulating the transforming growth factor-β1/Smad7 network and epithelial-mesenchymal transition in the intrahepatic metastasis Bagg's Albino/c mouse model

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Journal of Traditional Chinese Medicine 2024年第4期44卷 642-651页

作者： LYU Meixian zhou Huan zhi Limin zhou Jinling GAN Rizhi QIN Yanping HE Nengting ZUO Qiqi LI hao DONG Min LIANG Gang Pharmaceutical College Guangxi Medical UniversityNanning 530022China Department of Pharmacy Affiliated Tumor Hospital of Guangxi Medical UniversityNanning 530022China Drug clinical trial Facility office the People's Hospital of Guangxi Zhuang Autonomous RegionNanning 530022China College of Pharmacy Guangxi University of Chinese MedicineNanning 530022China Department of Pharmacy the Second Affiliated Hospital of Guangxi Medical UniversityNanning 530005China Department of Pharmacy People's Hospital of Guangxi HezhouHezhou 542899China Department of Pharmacy Guangzhou Women and Children's Medical Center Liuzhou HospitalLiuzhou 545000China Department of Pharmacy First Affiliated Hospital of Gannan Medical UniversityGannan 341000China

OBJECTIVE:To examine the influence of SaponinⅠfrom Shuitianqi(Rhizoma Schizocapasae Plantagineae)(SSPHⅠ)on hepatocellular carcinoma(HCC)metastasis,and to elucidate the underlying ***:The intrahepatic metastasis Bagg's Albino/c(BALB/c)mouse model was established with human hepatocellular carcinomas(HepG2)cells,then treated with normal saline(once per day),cisplatin(2 mg/kg,once every 2 d),and SSPHⅠ(25,50,and 75 mg/kg,once per day).Then,we assessed alterations in the hepatic pathology and target protein expressions in the intrahepatic metastasis BALB/c mouse model using a series of molecular biology ***:Based on our analysis,SSPHⅠsignificantly alleviated hepatocyte necrosis and tumor cells ***,SSPHⅠsuppressed extracellular matrix(ECM)degradation and angiogenesis via a decrease in matrix etalloproteinase-2(MMP-2),MMP-9,CD31,CD34,and vascular endothelial growth factor(VEGF)***,SSPHⅠrepressed invasion and metastasis by suppressing the transforming growth factor-β1(TGF-β1)/Smad7 axis and epithelial-mesenchymal transition(EMT),as evidenced by the scarce TGF-β1,Ncadherin,and Vimentin expressions,and elevated Smad7 and E-cadherin ***:The SSPHⅠ-mediated negative regulation of the TGF-β1/Smad7 axis and EMT are critical for the inhibition of HCC invasion and metastasis.

关键词： carcinoma,hepatocellular epithelial-mesenchymal transition transforming growth factor beta1 Smad7 protein Saponin I from Shuitianqi(Rhizoma Schizocapasae Plantagineae)

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Grain-boundary segregation and grain growth in nanocrystalline substitutional solid solution alloys

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Journal of Materials Science & Technology 2024年第1期168卷 239-249页

作者： Fawei Tang Chao Hou hao Lu zhi Zhao Xiaoyan Song Faculty of Materials and Manufacturing Key Laboratory of Advanced Functional MaterialsMinistry of Education of ChinaBeijing University of TechnologyBeijing 100124China

A model for describing solute segregation at grain boundaries has been developed for substitutional solid solution alloys,which integrates multiple factors from atomic to microstructural scales.A concept of mo-lar Gibbs free energy of segregation was introduced to evaluate the segregating capability of the solute elements in a closed system,through which the influences of grain boundary structure,grain size,ma-terial composition,and external conditions were *** on the evaluation of various energy forms related to solute segregation and grain growth processes,the nature of the thermal stabilization of nanograin structures by solute segregation was disclosed.A criterion for the destabilization of nanostruc-tures,which is determined by the competition of the change rates between the molar Gibbs free energy of segregation and the total energy of grain boundaries with grain size,has been *** study provided guideline to achieve high-temperature stability of nanograin structures of solid solution alloys even for the weakly segregating nanocrystalline systems.

关键词： Substitutional solid solution Grain boundary segregation Thermal stabilization Solute concentration Grain size

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