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Research on the knee region of cosmic ray by using a novel type of electron-neutron detector array

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Frontiers of physics 2024年第4期19卷 13-24页

作者： Bing-Bing Li Xin-Hua Ma Shu-Wang Cui Hao-Kun chen tian-lu chen Danzengluobu Wei Gao Hai-Bing Hu Denis Kuleshov Kirill Kurinov Hu Liu Mao-Yuan Liu Ye Liu Da-Yu Peng Yao-Hui Qi Oleg Shchegolev Yuri Stenkin Li-Qiao Yin Heng-Yu Zhang Liang-Wei Zhang College of Physics Hebei Normal UniversityShijiazhuang 050024China Key Laboratory of Particle Astrophysics Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China tianFU Cosmic Ray Research Center Chengdu 610000China College of Science Tibet UniversityLhasa 850000China Key Laboratory of Comic Rays Ministry of EducationTibet UniversityLhasa 850000China Institute for Nuclear Research of the Russian Academy of Sciences Moscow 117312Russia School of Physical Science and Technology Southwest Jiaotong UniversityChengdu 610031China School of Management Science and Engineering Hebei University of Economics and BusinessShijiazhuang 050061China Moscow Institute of Physics and Technology Moscow 141700Russia

By accurately measuring composition and energy spectrum of cosmic ray,the origin problem of so called“knee”region(energy>one PeV)can be ***,up to the present,the results of the spectrum in the knee region obtained by several previous experiments have shown obvious differences,so they cannot give effective evidence for judging the theoretical models on the origin of the ***,the Large High Altitude Air Shower Observatory(LHAASO)has reported several major breakthroughs and important results in astro-particle physics *** on its advantages of wide-sky survey,high altitude location and large area detector arrays,the research content of LHAASO experiment mainly includes ultra high-energy gamma-ray astronomy,measurement of cosmic ray spectra in the knee region,searching for dark matter and new phenomena of particle physics at higher *** electron and thermal neutron detector(EN-Detector)is a new scintillator detector which applies thermal neutron detection technology to measure cosmic ray extensive air shower(EAS).This technology is an extension of *** EN-Detector Array(ENDA)can highly efficiently measure thermal neutrons generated by secondary hadrons so called“skeleton”of *** this paper,we perform the optimization of ENDA configuration,and obtain expectations on the ENDA results,including thermal neutron distribution,trigger efficiency and capability of cosmic ray composition *** obtained real data results are consistent with those by the Monte Carlo simulation.

关键词： cosmic ray EAS knee region LHAASO ENDA

Application of deep learning methods combined with physical background in wide field of view imaging atmospheric Cherenkov telescopes

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Nuclear Science and Techniques 2024年第4期35卷 208-220页

作者： Ao-Yan cheng Hao Cai Shi chen tian-lu chen Xiang Dong You-Liang Feng Qi Gao Quan-Bu Gou Yi-Qing Guo Hong-Bo Hu Ming-Ming Kang Hai-Jin Li chen Liu Mao-Yuan Liu Wei Liu Fang-Sheng Min Chu-cheng Pan Bing-Qiang Qiao Xiang-Li Qian Hui-Ying Sun Yu-Chang Sun Ao-Bo Wang Xu Wang Zhen Wang Guang-Guang Xin Yu-Hua Yao Qiang Yuan Yi Zhang School of Physics and Technology Wuhan UniversityWuhan 430072China School of Physics and Astronomy Yunnan UniversityKunming 650091China Ministry of Education The Key Laboratory of Cosmic Rays(Tibet University)Lhasa 850000China Key Laboratory of Particle Astrophysics Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China University of Chinese Academy of Sciences 19 A Yuquan RoadShijingshan DistrictBeijing 100049China College of Physics Sichuan UniversityChengdu 610064China School of Intelligent Engineering Shandong Management UniversityJinan 250357China Tsung‑Dao Lee Institute Shanghai Jiao Tong UniversityShanghai 200240China Suzhou Aerospace Information Research Institute Suzhou 215123China College of Physics Chongqing UniversityNo.55 Daxuecheng South RoadHigh‑tech DistrictChongqing 401331China Key Laboratory of Dark Matter and Space Astronomy Purple Mountain ObservatoryChinese Academy of SciencesNanjing 210008China

The High Altitude Detection of Astronomical Radiation(HADAR)experiment,which was constructed in Tibet,China,combines the wide-angle advantages of traditional EAS array detectors with the high-sensitivity advantages of focused Cherenkov *** objective is to observe transient sources such as gamma-ray bursts and the counterparts of gravitational *** study aims to utilize the latest AI technology to enhance the sensitivity of HADAR *** datasets and models with distinctive creativity were constructed by incorporating the relevant physical theories for various *** models can determine the type,energy,and direction of the incident particles after careful *** obtained a background identification accuracy of 98.6%,a relative energy reconstruction error of 10.0%,and an angular resolution of 0.22°in a test dataset at 10 *** findings demonstrate the significant potential for enhancing the precision and dependability of detector data analysis in astrophysical *** using deep learning techniques,the HADAR experiment’s observational sensitivity to the Crab Nebula has surpassed that of MAGIC and *** energies below 0.5 TeV and remains competitive with conventional narrow-field Cherenkov telescopes at higher *** addition,our experiment offers a new approach for dealing with strongly connected,scattered data.

关键词： VHE gamma-ray astronomy HADAR Deep learning Convolutional neural networks

Gamma/Hadron Separation Method for the HADAR Experiment

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Research in Astronomy and Astrophysics 2024年第3期24卷 70-74页

作者： Yang-Zhao Ren tian-lu chen You-Liang Feng Dan-Zeng luo-Bu Yi-Qing Guo cheng Liu Qi Gao Mao-Yuan Liu Xiang-Li Qian Ya-Ping Wang Zi-Hao Zhang Xin-Long Li Qing-Yuan Hou Heng-Jiao Liu Qing-Qian Zhou Shan-Jie Shu The Key Laboratory of Cosmic Rays(Tibet University) Ministry of EducationLhasa 850000China Key Laboratory of Particle Astrophysics Institute of High Energy PhysicsChinese Academy of Sciences University of Chinese Academy of Sciences School of Intelligent Engineering Shandong Management University

Ground-based arrays of imaging atmospheric Cherenkov telescopes(IACTs)are the most sensitiveγ-ray detectors for energies of approximately 100 Ge V and *** such IACT is the High Altitude Detection of Astronomical Radiation(HADAR)experiment,which uses a large aperture refractive water lens system to capture atmospheric Cherenkov photons(i.e.,the imaging atmospheric Cherenkov technique).The telescope array has a low threshold energy and large field of view,and can continuously scan the area of the sky being observed,which is conducive to monitoring and promptly responding to transient *** process ofγ-hadron separation is essential in very-high-energy(>30 Ge V)γ-ray astronomy and is a key factor for the successful utilization of *** this study,Monte Carlo simulations were carried out to model the response of cosmic rays within the HADAR *** analyzing the Hillas parameters and the distance between the event core and the telescope,the distinction between air showers initiated byγ-rays and those initiated by cosmic rays was ***,a Quality Factor was introduced to assess the telescope’s ability to suppress the background and to provide a more effective characterization of its performance.

关键词： astroparticle physics-telescopes-methods data analysis

A novel trigger algorithm for wide-field-of-view imaging atmospheric Cherenkov technique experiments

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Nuclear Science and Techniques 2022年第3期33卷 22-28页

作者： Guang-Guang Xin Hao Cai Yi-Qing Guo tian-lu chen cheng Liu Xiang-Li Qian School of Physics and Technology Wuhan UniversityWuhan 430072China Key Laboratory of Particle Astrophysics Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China Ministry of Education The Key Laboratory of Cosmic Rays(Tibet University)Lhasa 850000China School of Intelligent Engineering Shandong Management UniversityJinan 250357China

The high-altitude detection of astronomical radiation(HADAR)experiment is a new Cherenkov observation technique with a wide field of view(FoV),aimed at observing the prompt emissions ofγ-ray bursts(GRBs).The bottleneck for this type of experiment can be found in determining how to reject the high rate of nightsky background(NSB)noise from random *** this work,we propose a novel method for rejecting noise,which considers the spatial properties of GRBs and the temporal characteristics of Cherenkov *** space coordinates,the map between the celestial sphere and the fired photomultiplier tubes(PMTs)on the telescope's camera can be expressed as f(δ(i,j))=δ'(i',j'),which means that a limited number of PMTs is selected from one *** the temporal scale,a 20-ns time window was selected based on the knowledge of Cherenkov *** allowed integration of the NSB for a short time ***,the angular resolution and effective area at 100 GeV in the HADAR experiment were obtained as 0.2°and 10^(4)m^(2),*** method can be applied to all wide-FoV experiments.

关键词： IACTs Wide field of view(FoV) γ-ray burst Cherenkov radiation

Soybean(Glycine max)rhizosphere organic phosphorus recycling relies on acid phosphatase activity and specific phosphorusmineralizing-related bacteria in phosphate deficient acidic soils

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Journal of Integrative Agriculture 2024年第5期23卷 1685-1702页

作者： Qianqian chen Qian Zhao Baoxing Xie Xing lu Qi Guo Guoxuan Liu Ming Zhou Jihui tian Weiguo lu Kang chen Jiang tian Cuiyue Liang Root Biology Center State Key Laboratory for Conservation and Utilization of Subtropical Agro-BioresourcesCollege of Natural Resources and EnvironmentSouth China Agricultural UniversityGuangzhou 510642China College of Natural Resources and Environment South China Agricultural UniversityGuangzhou 510642China Henan Academy of Crops Molecular Breeding Henan Academy of Agricultural SciencesZhengzhou 450002China

Bacteria play critical roles in regulating soil phosphorus(P) cycling. The effects of interactions between crops and soil P-availability on bacterial communities and the feedback regulation of soil P cycling by the bacterial community modifications are poorly understood. Here, six soybean(Glycine max) genotypes with differences in P efficiency were cultivated in acidic soils with long-term sufficient or deficient P-fertilizer treatments. The acid phosphatase(AcP) activities, organic-P concentrations and associated bacterial community compositions were determined in bulk and rhizosphere soils. The results showed that both soybean plant P content and the soil AcP activity were negatively correlated with soil organic-P concentration in P-deficient acidic soils. Soil P-availability affected the ɑ-diversity of bacteria in both bulk and rhizosphere soils. However, soybean had a stronger effect on the bacterial community composition, as reflected by the similar biomarker bacteria in the rhizosphere soils in both P-treatments. The relative abundance of biomarker bacteria Proteobacteria was strongly correlated with soil organic-P concentration and AcP activity in low-P treatments. Further high-throughput sequencing of the phoC gene revealed an obvious shift in Proteobacteria groups between bulk soils and rhizosphere soils, which was emphasized by the higher relative abundances of Cupriavidus and Klebsiella, and lower relative abundance of Xanthomonas in rhizosphere soils. Among them, Cupriavidus was the dominant phoC bacterial genus, and it was negatively correlated with the soil organic-P concentration. These findings suggest that soybean growth relies on organic-P mineralization in P-deficient acidic soils, which might be partially achieved by recruiting specific phoCharboring bacteria, such as Cupriavidus.

关键词： organic phosphorus acid phosphatase soybean bacterial community phoC-harboring bacteria rhizosphere

Two New r-process-enhanced Stars with [Fe/H] >-0.6 dex from the LAMOST-MRS Survey

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Research in Astronomy and Astrophysics 2022年第7期22卷 109-117页

作者： Xiao-Jin Xie Jian-Rong Shi tian-lu chen Hong-Liang Yan tian-Yi chen Kai-Ke Pan Chun-Qian Li Shuai Liu Qi Gao Tai-Sheng Yan Ming-Yi Ding Department of Physics College of ScienceTibet UniversityLhasa 850000China Key Laboratory of Optical Astronomy National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China Key Laboratory of Cosmic Rays(Tibet University) Ministry of EducationLhasa 850000China School of Astronomy and Space Science University of Chinese Academy of SciencesBeijing 100049China Apache Point Observatory SunspotNew Mexico 88349USA Astronomy Department New Mexico State UniversityLas CrucesNew Mexico 88003USA

We report the discovery of two r-process-enhanced stars with [Fe/H]>-0.6 dex selected from the Large Sky Area Multi-Object Fiber Spectroscopic Telescope(LAMOST) *** candidate stars have been selected from the LAMOST medium-resolution(R~ 7500) spectroscopic survey,and the follo wed-up high signal-to-noise ratio and high-resolution(R~31,500) spectra are obtained with the ARC Echelle Spectrograph mounted on the3.5 m telescope at the Apache Point Observatory,which allow us for the determination of stellar atmospheric parameters and abundances of 20 *** these three r-process-enhanced candidate stars,TYC 1710-933-1 and TYC 2858-372-1 have [Eu/Fe] higher than 0.3 dex and [Ba/Eu] lower than 0.0 dex,thus,can be identified as new r-process-enhanced *** 2858-372-1 shows similar r+s-process pattern to the *** 1710-933-1 presents enhancement of the r-process elements of Nd and *** work indicates that the enrichment mechanisms of the heavy neutron-capture elements are complicated for metal-rich stars.

关键词： stars:abundances stars:chemically peculiar stars:fundamental parameters

Alisol B 23-acetate promotes white adipose tissue browning to mitigate high-fat diet-induced obesity by regulating mTOR-SREBP1 signaling

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Journal of Integrative Medicine 2024年第1期22卷 83-92页

作者： lu-lu Han Xin Zhang Hui Zhang Ting Li Yi-chen Zhao Ming-hui tian Feng-lei Sun Bo Feng Department of Neurology Three The Fifth People’s Hospital of JinanJinan 250013Shandong ProvinceChina Department of Gastroenterology Affiliated Hospital of Shandong University of Traditional Chinese MedicineJinan 250014Shandong ProvinceChina The First Clinical Medical College Shandong University of Traditional Chinese MedicineJinan 250014Shandong ProvinceChina Department of Geriatrics the First Affiliated Hospital of Shandong First Medical University(Shandong Provincial Qianfoshan Hospital)Jinan 250014Shandong ProvinceChina Chinese Medicine Culture and Literature Research Institute Shandong University of Traditional Chinese MedicineJinan 250014Shandong ProvinceChina Department of General Medicine Affiliated Hospital of Shandong University of Traditional Chinese MedicineJinan 250014Shandong ProvinceChina Department of Traditional Chinese Medicine the Second People’s Hospital of Haibei PrefectureZangzu Autonomous Prefecture of Haibei810300Qinghai ProvinceChina

Objective Obesity is a global health concern with management strategies encompassing bariatric surgery and anti-obesity drugs;however,concerns regarding complexities and side effects persist,driving research for more effective,low-risk *** promotion of white adipose tissue(WAT)browning has emerged as a promising ***,alisol B 23-acetate(AB23A)has demonstrated efficacy in addressing metabolic disorders,suggesting its potential as a therapeutic agent in obesity ***,in this study,we aimed to investigate the therapeutic potential of AB23A for mitigating obesity by regulating metabolic phenotypes and lipid distribution in mice fed a high-fat diet(HFD).Methods An obesity mouse model was established by administration of an *** and insulin metabolism were assessed via glucose and insulin tolerance *** size was determined using hematoxylin and eosin *** expression of browning markers in WAT was evaluated using Western blotting and quantitative real-time polymerase chain *** cage monitoring involved the assessment of various parameters,including food and water intake,energy metabolism,respiratory exchange rates,and physical ***,oil red O staining was used to evaluate intracellular lipid accumulation.A bioinformatic analysis tool for identifying the molecular mechanisms of traditional Chinese medicine was used to examine AB23A targets and associated signaling *** AB23A administration significantly reduced the weight of obese mice,decreased the mass of inguinal WAT,epididymal WAT,and perirenal adipose tissue,improved glucose and insulin metabolism,and reduced adipocyte ***,treatment with AB23A promoted the expression of browning markers in WAT,enhanced overall energy metabolism in mice,and had no discernible effect on food intake,water consumption,or physical *** 3T3-L1 cells,AB23A inhibited lipid accumulation,and both AB23A and rapamycin inhibited t

关键词： Obesity Alisol B 23-acetate Adipose tissue mTOR-SREBP1 High-fat diet

A toroidal SAW gyroscope with focused IDTs for sensitivity enhancement

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Microsystems & Nanoengineering 2024年第2期10卷 47-56页

作者： lu tian Haitao Zhao Qiang Shen Honglong Chang Ministry of Education Key Laboratory of Micro and Nano Systems for Aerospace School of Mechanical EngineeringNorthwestern Polytechnical UniversityXi’an710072China

A surface acoustic wave(SAW)gyroscope measures the rate of rotational angular velocity by exploiting a phenomenon known as the SAW gyroscope *** a gyroscope is a great candidate for application in harsh environments because of the simplification of the suspension vibration mechanism necessary for traditional microelectromechanical system(MEMS)***,for the first time,we propose a novel toroidal standing-wave-mode SAW gyroscope using focused interdigitated transducers(FIDTs).Unlike traditional SAW gyroscopes that use linear IDTs to generate surface acoustic waves,which cause beam deflection and result in energy dissipation,this study uses FIDTs to concentrate the SAW energy based on structural features,resulting in better focusing performance and increased SAW *** experimental results reveal that the sensitivity of the structure is 1.51µV/(°/s),and the bias instability is 0.77°/s,which are improved by an order of magnitude compared to those of a traditional SAW ***,the FIDT component can enhance the performance of the SAW gyroscope,demonstrating its superiority for angular velocity *** work provides new insights into improving the sensitivity and performance of SAW gyroscopes.

关键词： angular deflection gyroscope

Energy beam-based direct and assisted polishing techniques for diamond:A review

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International Journal of Extreme Manufacturing 2024年第1期6卷 93-124页

作者： Zhuo Li Feng Jiang Zhengyi Jiang Zige tian tian Qiu Tao Zhang Qiuling Wen Xizhao lu Jing lu Hui Huang Institute of Manufacturing Engineering Huaqiao UniversityXiamen 361021People’s Republic of China School of Mechanical MaterialsMechatronic and Biomedical EngineeringUniversity of WollongongWollongongNSW 2522Australia College of Mechanical Engineering and Automation Huaqiao UniversityXiamen 361021People’s Republic of China State Key Laboratory of High Performance Tools Huaqiao UniversityXiamen 361021People’s Republic of China

Diamond is a highly valuable material with diverse industrial applications,particularly in the fields of semiconductor,optics,and high-power ***,its high hardness and chemical stability make it difficult to realize high-efficiency and ultra-low damage machining of *** address these challenges,several polishing methods have been developed for both single crystal diamond(SCD)and polycrystalline diamond(PCD),including mechanical,chemical,laser,and ion beam processing *** this review,the characteristics and application scope of various polishing technologies for SCD and PCD are ***,various energy beam-based direct and assisted polishing technologies,such as laser polishing,ion beam polishing,plasma-assisted polishing,and laser-assisted polishing,are *** current research progress,material removal mechanism,and infuencing factors of each polishing technology are *** some of these methods can achieve high material removal rates or reduce surface roughness,no single method can meet all the ***,the future development prospects and application directions of different polishing technologies are presented.

关键词： single crystal diamond polycrystalline diamond energy beam polishing technology material removal mechanism influencing factors