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Research on the measurement and shielding methods of the spatial electromagnetic radiation of the BEPCⅡlinac

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Radiation Detection Technology and Methods 2022年第2期6卷 187-193页

作者： Hua Shi Xiang He jing-Dong liu jing-ru Zhang Xiao-Ping li National Synchrotron Radiation Laboratory University of Science and Technology of ChinaHefei 230029China Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China

Purpose The research focuses on the related measurement and shielding works for solving the spatial electromagnetic radiation and interference problems of the BEPCⅡ*** The radiation frequency and intensity can be determined by using a set of antennas connected with a spectrum *** The source of the radiation is located on the cable connectors of some device *** radiation intensity is significantly reduced after wrapping the connectors with the radiation shielding *** The entire research process includes the selection of a domestically made ultra-wideband antenna,the proposal of the measurement methods,the locating of the radiation source,the performance measurement of the radiation shielding tape and the shielding of the *** provides a whole set of feasible solutions for similar problems in accelerators.

关键词： BEPCⅡ linac Spatial electromagnetic radiation Radiation measurement Radiation shielding Ultra-wideband antenna

Numerical simulation of spatial distributions of mining-induced stress and fracture fields for three coal mining layouts

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Journal of Rock Mechanics and Geotechnical Engineering 2018年第5期10卷 907-913页

作者： Shengwei li Mingzhong Gao Xiaojun Yang ru Zhang li Ren Zhaopeng Zhang Guo li Zetian Zhang jing Xie State Key Laboratory of Hydraulics and Mountain River Engineering College of Water Resource and Hydropower Sichuan University State Key Laboratory for Geomechanics and Deep Underground Engineering China University of Mining and Technology MOE Laboratory of Deep Underground Science and Engineering College of Architecture and Environment Sichuan University China Three Gorges Projects Development Co. Ltd.

In this study, the spatial distributions of stress and fracture fields for three typical underground coal mining layouts, Le, non-pillar mining （NM）, top-coal caving mining （TCM） and protective coal-seam mining （PCM）, are modeled using discrete element software UDEC, The numerical results show that different mining layouts can lead to different mining-induced stress fields, resulting in diverse fracture fields, For the PCM, the mining influenced area in front of the mining faces is the largest, and the stress concentration factor in front of the mining faces is the lowest, The spatial shapes of the mining-induced fracture fields under NM, TCM and PCM differ, and they are characterized by trapezoidal, triangular and tower shapes, respectively, The fractal dimensions of mining-induced fractures of the three mining layouts decrease in the order of PCM, TCM and NM, It is also shown that the PCM can result in a better gas control effect in coal mines with high outburst potential, The numerical results are expected to provide a basis for understanding of mining-induced gas seepage fields and provide a reference for high- efficiency coal mining,

关键词： Coal mining Mining layouts Mining-induced stress field Mining-induced fracture field Numerical simulation

Probing granular inhomogeneity of a particle-emitting source by imaging two-pion Bose–Einstein correlations

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Nuclear Science and Techniques 2021年第2期32卷 81-89页

作者： li-Ya li Peng ru Ying Hu School of Mathematics and Economics Hubei University of EducationWuhan 430205HubeiChina Guangdong Provincial Key Laboratory of Nuclear Science Institute of Quantum MatterSouth China Normal UniversityGuangzhou 510006China

Using the source imaging technique in two-pion interferometry,we study the image of the hydrodynamic particle-emitting source with the HIjing initial conditions for relativistic heavy-ion collisions on an event-by-event *** is shown that the initial-state fluctuations may give rise to bumpy structures of the medium during hydrodynamical evolution,which affects the two-pion emission space and leads to a visible two-tiered shape in the source function imaged using the two-pion Bose–Einstein *** two-tiered shape can be understood within a similar but more analytic granular source model and is found to be closely related to the introduced quantity n,which characterizes the granular inhomogeneity of the *** fitting the imaged source function with a granular source parametrization,we extract the granular inhomogeneity of the hydrodynamic source,which is found to be sensitive to both the Gaussian smearing width of the HIjing initial condition and the centrality of the collisions.

关键词： Heavy-ion collision Bose-Einstein correlations Imaging technique

A New Half-life Value of ^(79)Se

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Chinese Physics Letters 1996年第1期13卷 9-12页

作者： HANG Song-sheng GUO jing-ru JIANG Shan li Chun-sheng CUI An-zhi HE Ming China Institute of Atomic Energy Beijing 102413

In the recent charts of the nuclides an accepted half-life of ^(79)Se is only an upper limit,<6.5×10^(4)*** this letter,A new half-life of ^(79)Se has been measured tobe(1.13±0.17)×10^(6)*** number of ^(79)Se atoms... 详细信息

In the recent charts of the nuclides an accepted half-life of ^(79)Se is only an upper limit,life of ^(79)Se has been measured tobe(1.13±0.17)×10^(6)*** number of ^(79)Se atoms was determined from measured ^(79)Se/Se ratios with the accelerator mass spectrometry technique and the decay rate of ^(79)Se was determined by counting the emitted β rays with a liquid scintillationspectrorneter.

关键词： letter decay limit

Long-read sequencing reveals novel genetic polymorphisms in the major histocompatibility complex region and their impacts on the Han Chinese population

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Science China life Sciences 2025年

作者： Cong Zhou Tingting Gong Shuhang li li Jin Shaohua Fan State Key Laboratory of Genetic Engineering Lab for Evolutionary Synthesis School of Life Sciences Human Phenome Institute Fudan University Research Unit of Dissecting the Population Genetics and Developing New Technologies for Treatment and Prevention of Skin Phenotypes and Dermatological Diseases (2019ru058) Chinese Academy of Medical Sciences

Human leukocyte antigen(HLA) genes in the major histocompatibility complex(MHC) region are crucial for immunity and are associated with numerous diseases and phenotypes. The MHC region's complexity and high genetic diversity make it challenging to analyze using short-read sequencing(SRS) technology. We sequence the MHC region of 100 Han Chinese individuals using both long-read sequencing(LRS) and SRS platforms at approximately 30X coverage to study genetic alterations and their potential functional impacts. LRS provides significantly greater coverage of the MHC region and eight classical HLA genes, particularly at the HLA-DRB1 locus, compared with SRS. We detect 78,249 single nucleotide polymorphisms(SNPs) using LRS, with 26.0% undetectable by SRS. Based on SNP and inferred HLA allele types, we construct an LRS-based MHC reference panel for the Han Chinese, containing approximately 2.6 times more genetic variants than the SRS-based Han-MHC reference panel. A phenome-wide association study assessing 26,024 phenotypes across 15 categories identifies significant associations for 7,879 independent variants(including 809 LRS-specific SNPs) with 409 phenotypes in nine categories. This analysis reveals 24 unreported HLA allele associations in the bioelectric and cellular categories. The conditional analysis identifies 530independent signals across the 409 phenotypes, including 28 previously unreported signals of eight classical HLA genes associated with 33phenotypes. Of the top-associated SNPs, 191 are detected by LRS only. Fine-mapping identifies 126 independent candidate causal SNPs for three immune-related cellular phenotypes, with 17 detected exclusively by LRS. Our study reveals previously unreported variants and their functional impacts in the MHC region, enhancing our understanding of genetic diversity and its potential biological implications in the Han Chinese population.

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现象学视域下农村集体经济的本质再诠释

西北农林科技大学学报（社会科学版） 2025年第1期25卷 60-68页

作者：李林峰刘启明饶静中国农业大学人文与发展学院北京100083 中共江西省委党校江西经济社会发展战略研究所南昌330108

鉴于当前政策、理论和实践领域对农村集体经济本质缺乏共识,本研究采用胡塞尔现象学的方法论,特别是一般现象学还原、本质还原和先验还原等技术,系统地审视了“农村集体经济应该是什么”这一核心议题。通过全面梳理当前对农村集体经济... 详细信息

鉴于当前政策、理论和实践领域对农村集体经济本质缺乏共识,本研究采用胡塞尔现象学的方法论,特别是一般现象学还原、本质还原和先验还原等技术,系统地审视了“农村集体经济应该是什么”这一核心议题。通过全面梳理当前对农村集体经济的多维认知,从而为其本质探索提供更为宽广的视角。在搁置既有认识的基础上,采用更加开放的态度识别出土地集体所有制是农村集体经济的共相,这一发现为理解其本质提供了关键线索。进一步从源初意向性与结构性剖析农村集体经济,揭示其本质在于注重公正,并凸显了其深厚的社会性和伦理性。这种本体论式反思既验证了马克思主义理论关于集体所有制经济的科学性及其生命力,更展示了中国农村集体经济独有的文化烙印。同时,跨学科的研究方法或为理解农村集体经济提供了新的视角,为推动其持续健康发展提供有益的思考。

关键词：农村集体经济现象学本质

Red light at intensities above 10lx alters sleep–wake behavior in mice

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light(Science & Applications) 2016年第1期5卷 150-159页

作者： Ze Zhang Hui-jing Wang Dian-ru Wang Wei-Min Qu Zhi-li Huang Institutes of Brain Science and Collaborative Innovation Center for Brain Science Department of PharmacologySchool of Basic Medical SciencesState Key Laboratory of Medical Neurobiology and Shanghai Key Laboratory of Clinical Geriatric MedicineShanghai Medical CollegeFudan UniversityShanghai 200032China

Sleep is regulated by two mechanisms:the homeostatic process and the circadian *** affects sleep and alertness by entraining the circadian clock,and acutely inducing sleep/alertness,in a manner mediated by intrinsically photosensitive retinal ganglion *** intrinsically photosensitive retinal ganglion cells are believed to be minimally sensitive to red light,which is widely used for illumination to reduce the photic disturbance to nocturnal animals during the dark ***,the appropriate intensity of the red light is *** the present study,we recorded electroencephalograms and electromyograms of freely moving mice to investigate the effects of red light emitted by light-emitting diodes at different intensities and for different durations on the sleep–wake behavior of *** light was used as a ***,red light exerted potent sleep-inducing effects and changed the sleep architecture in terms of the duration and number of sleep episodes,the stage transition,and the EEG power density when the intensity was 420 ***,we lowered the light intensity and demonstrated that red light at or below 10 lx did not affect sleep–wake *** light markedly induced sleep and disrupted sleep architecture even at an intensity as low as 10 *** findings highlight the importance of limiting the intensity of red light(⩽10 lx)to avoid optical influence in nocturnal behavioral experiments,particularly in the field of sleep and circadian research.

关键词： circadian light light-emitting diode masking

Design and synthesis of new 7,8-dimethoxy-α-naphthoflavones as CYP1A1 inhibitors

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Chinese Chemical Letters 2013年第3期24卷 215-218页

作者： Jia-Hua Cui Dagula Hu Xu Zhang Zheng jing jing Ding ru-Bing Wang Shao-Shun li School of Pharmacy Shanghai Jiaotong University

The flavonoids as inhibitors of CYP1A1 exhibit chemopreventive effects against certain procarcinogens and have been considered as the promising cancer preventive agents. A series of novel 7,8-dimethoxy-a- naphthoflavones as the substrate analogs were designed and prepared, The enzyme assay suggested that all of these new flavones were stronger inhibitors of CYP1A1 than the lead compound a-naphthoflavone, Among the tested ones, 3h showed the most potent inhibitory effects,

关键词： a-NaphthoflavoneCYPIA1 inhibitors7 8-Dimethoxy-a-naphthoflavoneFlavonoids

An Unprecedented 1D Zigzag Chain Alkaline Earth Metal Derivative {[Ba(DMF)_3(H_2O)_2][Ba(DMF)_4]_2(P_2W_(18)O_(62))}_n Containing Dawson Heteropolyanion

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Chinese Chemical Letters 2006年第6期17卷 817-820页

作者： jing Ping WANG Jian ru MA jing Yang NIU School of Chemistry and Chemical Engineering Henan University Kaifeng 475001

An unprecedented 1D zigzag chain alkaline earth metal derivative, {[Ba（DMF）3 （H20）2][Ba（DMF）412（P2W18O62）}n, （DMF=N, N-dimethyl formamide） containing Dawson hetero- polyanion has been successfully synthesized and characterized by X-ray crystallography. Two barium cations bridged by three DMF ligands in parallel combination with the Dawson-type heteropolyanion [P2W18O62]^6- and then the resulting subunits {[Ba（DMF）4]2（P2WlsO62）}^2＋ are alternately linked together via another [Ba（DMF）3（H2O）2]^2＋ ions, constructing a 1D zigzag chain architecture.

关键词： Polyoxometalate crystal structure Dawson structure.