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Observation of spectral lines in the exceptional GRB 221009A

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Science China(Physics,Mechanics & Astronomy) 2024年第8期67卷 187-206页

作者： Yan-Qiu Zhang Shao-Lin Xiong Ji-Rong Mao Shuang-Nan Zhang Wang-Chen Xue Chao Zheng jia-Cong Liu Zhen Zhang Xi-Lu Wang Ming-Yu Ge Shu-Xu Yi Li-Ming Song Zheng-Hua An Ce Cai Xin-qiao Li Wen-Xi Peng Wen-Jun Tan Chen-Wei Wang Xiang-yang Wen Yue Wang Shuo Xiao Fan Zhang Peng Zhang Shi-Jie Zheng Key Laboratory of Particle Astrophysics Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China University of Chinese Academy of Sciences Beijing 100049China Yunnan Observatories Chinese Academy of SciencesKunming 650011China Center for Astronomical Mega-Science Chinese Academy of SciencesBeijing 100012China Key Laboratory for the Structure and Evolution of Celestial Objects Chinese Academy of SciencesKunming 650216China College of Physics and Hebei Key Laboratory of Photophysics Research and Application Hebei Normal UniversityShijiazhuang 050024China Guizhou Provincial Key Laboratory of Radio Astronomy and Data Processing Guizhou Normal UniversityGuiyang 550001China College of Electronic and Information Engineering Tongji UniversityShanghai 201804China

As the brightest gamma-ray burst ever observed,GRB 221009A provided a precious opportunity to explore spectral line *** this article,we performed a comprehensive spectroscopy analysis of GRB 221009A jointly with GECAM-C and Fermi/GBM data to search for emission and absorption *** the first time we investigated the line feature throughout this GRB including the most bright part where many instruments suffered problems,and identified prominent emission lines in multiple time *** central energy of the Gaussian emission line evolves from about 37 to 6 MeV,with a nearly constant ratio(about 10%)between the line width and central ***,we find that both the central energy and the energy flux of the emission line evolve with time as a power law decay with power law index of–1 and–2,*** suggest that the observed emission lines most likely origin from the blue-shifted electron positron pair annihilation 511 ke V *** find that a standard high latitude emission scenario cannot fully interpret the observation,thus we propose that the emission line comes from some dense clumps with electron positron pairs traveling together with the *** this scenario,we can use the emission line to directly,for the first time,measure the bulk Lorentz factor of the jet(Γ)and reveal its time evolution(i.e.,Γ~t^(-1))during the prompt ***,we find that the flux of the annihilation line in the co-moving frame keeps *** discoveries of the spectral line features shed new and important lights on the physics of GRB and relativistic jet.

关键词： GRB GRB 221009A emission line

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前进接触线薄液膜结构与运移机制

物理学报 2024年第1期73卷 277-284页

作者：刘乔黄家宸王昊邓亚骏中国石化石油勘探开发研究院北京102206 北京大学工学院北京100871 深圳技术大学聚龙学院深圳518118

气-液-固三相接触线薄液膜微观结构认识不清使得动态接触角预测问题始终存在争议.本文通过大规模分子动力学模拟研究液滴动态润湿过程,获得了完全浸润液滴前进接触线区域的前驱液膜结构、部分浸润液滴前进接触线区域的纳米级凸起结构.... 详细信息

气-液-固三相接触线薄液膜微观结构认识不清使得动态接触角预测问题始终存在争议.本文通过大规模分子动力学模拟研究液滴动态润湿过程,获得了完全浸润液滴前进接触线区域的前驱液膜结构、部分浸润液滴前进接触线区域的纳米级凸起结构.首次在模拟中获得了微观接触角与宏观接触角随时间的动态演变规律.分子轨迹追踪揭示了接触线薄液膜区域流体在固体表面摩擦作用下,随速度增大从滑动为主向滚动为主的模式转变,进而在底层出现气体裹挟导致滑移、发生溅射的机制.本研究为进一步构建普适的动态接触角预测模型提供了关键物理依据.

关键词：接触线薄液膜润湿界面分子模拟

维普期刊数据库博看期刊

Acid mine drainage activation mechanism on lime-depressed pyrite flotation from copper sulfide ore

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Transactions of Nonferrous Metals Society of China 2024年第9期34卷 2987-3001页

作者： jia-qiao YUAN Zhan DING Yun-xiao BI Jie LI Shu-ming WEN Shao-jun BAI Faculty of Land Resource Engineering Kunming University of Science and TechnologyKunming 650093China State Key Laboratory of Complex Nonferrous Metal Resources Clean Utilization Kunming University of Science and TechnologyKunming 650093China Yunnan Key Laboratory of Green Separation and Enrichment of Strategic Mineral Resources Kunming University of Science and TechnologyKunming 650093China

The lime-depressed pyrite from Cu differential flotation tailings with acid mine drainage(AMD)as a natural activator was *** effect of AMD on lime-depressed pyrite flotation was investigated by a series of laboratory flotation tests and surface analytical *** test results indicated that AMD could effectively activate the pyrite flotation with a sodium butyl xanthate(SBX)collector,and a high-quality sulfur concentrate was *** ion concentration analysis results indicated that AMD facilitated desorption of Ca~(2+)and adsorption of Cu~(2+)on the depressed-pyrite *** measurements and contact angle analysis results confirmed that adding AMD improved the adsorption amount of SBX collector on the pyrite surface and increased the contact angle by 31°.Results of Raman spectroscopy and X-ray photoelectron spectroscopy analysis indicated that AMD treatment promoted the formation of hydrophobic species(S~0 hydrophobic entity and copper sulfides)and the removal of hydrophilic calcium and iron species on the pyrite surface,which reinforced the adsorption of *** findings of the present research provide important theoretical basis and technical support for a cleaner production of copper sulfide ores.

关键词： copper sulfur ore acid mine drainage lime-depressed pyrite flotation natural activator activation mechanism

乡村地域多功能演化与土地利用转型耦合研究进展与展望

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地理研究 2024年第6期43卷 1556-1571页

作者：乔伟峰李琛戴凌玲贾铠阳杨春花南京师范大学地理科学学院南京210023 江苏省地理信息资源开发与利用协同创新中心南京210023 南京师范大学乡村振兴研究院南京210023 南京大学地理与海洋科学学院南京210023

在快速城镇化和工业化进程中,乡村地区出现了一系列土地利用和地域功能失调现象,两者动态关系成为乡村地理学的研究焦点。本文系统回顾了乡村地域功能与土地利用转型的研究进展,尝试厘清两者耦合关联研究思路、内容与趋势,并在此基础上... 详细信息

在快速城镇化和工业化进程中,乡村地区出现了一系列土地利用和地域功能失调现象,两者动态关系成为乡村地理学的研究焦点。本文系统回顾了乡村地域功能与土地利用转型的研究进展,尝试厘清两者耦合关联研究思路、内容与趋势,并在此基础上提出了未来乡村地域多功能演化与土地利用转型耦合研究展望。研究结论表明,乡村地理学在乡村多功能与土地利用转型领域已取得显著的进展,两者交互作用关系也得到了学界的关注。但目前,两者的耦合过程、机理、模式等研究仍处于探索阶段,存在耦合互馈关系未能整体刻画、耦合机理解析视角有待拓展、针对不同乡村地域主体功能导向下的土地资源优化配置的案例研究还尚不多见等问题。未来乡村地域多功能演化与土地利用转型耦合研究应以“耦合框架构建-耦合过程刻画-耦合机理解析-耦合状态调控”为研究主线,加强乡村地理学与土地系统科学两个领域的交叉融通,为乡村地区可持续发展提供科学支撑。

关键词：乡村地理学土地系统科学乡村多功能乡村振兴空间治理

不确定环境下的航空发动机装配线适应性调度方法

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控制与决策 2024年第5期39卷 1629-1635页

作者：王怡琳刘鹃乔非张家谔同济大学电子与信息工程学院上海201800 中国航空制造技术研究院北京100020

航空发动机装配是航空发动机制造过程的关键环节,其工序多,流程复杂,生产过程中扰动频发,如装配时间波动、不合格返工等.针对不确定环境下的航空发动机装配线的调度问题,提出一种基于门控循环神经网络(GRU)的适应性调度方法.该调度方法... 详细信息

航空发动机装配是航空发动机制造过程的关键环节,其工序多,流程复杂,生产过程中扰动频发,如装配时间波动、不合格返工等.针对不确定环境下的航空发动机装配线的调度问题,提出一种基于门控循环神经网络(GRU)的适应性调度方法.该调度方法包含扰动识别和调度规则调整两个部分:扰动识别模块以滑动时间窗口为周期,利用GRU神经网络进行渐近型扰动的识别;调度规则调整模块以扰动识别的结果为触发,通过构建基于GRU神经网络的调度规则决策模型,输出适配当前生产状态的新的调度规则,用以指导生成更新的调度方案.最后,以某航空发动机装配线为研究案例,对所提出适应性调度方法进行验证分析.对比实验结果表明,所提出方法能够有效提升装配线的设备利用率、日均生产率等性能.

关键词：适应性调度扰动识别深度学习门控循环神经网络航空发动机装配调度规则

Multidisciplinary and multiscale nanoscience research roadmap based on large scientific facilities

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Science China Chemistry 2024年第8期67卷 2497-2523页

作者： Yuan Zeng Shuhan Zhang Yuecong Guo Yalin Cong Xu Ding Peihua Li Yunxiang Lin Wenzhi Ren Hui Su Weigang Sun Liuxin Xu Guikai Zhang Shihua Chen Yu Chen Weiren Cheng Shengqi Chu Yong Guan Jinru Han Jie Lin Hengjie Liu Zheyi Liu Pan Luo Fanchun Meng Sicong qiao Zongyin Song Ying Wang Zhao Wu Chenyu yang Meng yang Shirui yang Zi Yin Zhibin Yin Pengjun Zhang Hongyu Zhang Pingping Zheng jia Zhou Wanlin Zhou Pengfei An He Cheng Chunhai Fan Xingjiu Huang Yong Lei Lina Li Mu Li Qinghua Liu Shuming Peng Li Song Zhihu Sun yangchao Tian Fangjun Wang Lihua Wang Liming Wang Shiqiang Wei Aiguo Wu Chunlei Xiao Xueming yang Panchao Yin Jing Zhang Mingxin Zhang Yaling Wang Chunying Chen CAS Key Laboratory for Biomedical Effects of Nanomaterials and Nanosafety New Cornerstone Science LaboratoryNational Center for Nanoscience and TechnologyBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China National Synchrotron Radiation Laboratory University of Science and Technology of ChinaHefei 230029China Institute of Solid State Physics Hefei Institutes of Physical ScienceChinese Academy of SciencesHefei 230031China Institutes of Physical Science and Information Technology Anhui UniversityHefei 230601China Ningbo Key Laboratory of Biomedical Imaging Probe Materials and Technology Zhejiang International Cooperation Base of Biomedical Materials Technology and ApplicationCAS Key Laboratory of Magnetic Materials and DevicesNingbo Cixi Institute of Biomedical EngineeringZhejiang Engineering Research Center for Biomedical MaterialsNingbo Institute of Materials Technology and EngineeringChinese Academy of SciencesNingbo 315201China Advanced Energy Science and Technology Guangdong Laboratory Huizhou 516000China College of Chemistry and Chemical Engineering Hunan Normal UniversityChangsha 410081China State Key Laboratory of Luminescent Materials and Devices South China Advanced Institute for Soft Matter Science and TechnologySouth China University of TechnologyGuangzhou 510640China Beijing Synchrotron Radiation Facility Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China CAS Key Laboratory of Separation Sciences for Analytical Chemistry Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China State Key Laboratory of Molecular Reaction Dynamics Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China Institute of Advanced Science Facilities Shenzhen 518107China State Key Laboratory of Coal Conversion Institute of Coal ChemistryChinese Academy of SciencesTaiyuan 030001China State Key Laboratory of Particle Detection and Electronics Institute of High Energy PhysicsChinese Acade

With the advancement of modern science and technology, large scientific facilities are increasingly oriented toward demand and application, and can be used for basic research as well as serving multiple disciplines. Developing large scientific facilities and related analytical technologies enhances understanding of large scientific facilities and popularizes their application in research across multiple disciplines. The combination of light or neutron sources from large scientific facilities and advanced analytical technologies can be achieved for materials structure information, dynamics study of chemical reactions, high dissociation of biomolecules, 3D visualization of energy materials or biological samples, etc. We first introduce the progress of domestic large scientific facilities of synchrotron radiation(SR) and free electron lasers(FELs) with different wavelengths and neutron *** further discuss the comparison between Chinese and typical foreign facilities in X-ray radiation from X-ray tubes, synchrotrons, X-ray FELs, and neutron sources based on physical parameters of light and neutron sources. In addition, we focus on the technological progress and perspectives combined with advanced X-ray radiation and neutron sources of large scientific facilities in China, especially in the nanoscience fields of energy catalysis and biological science. We hope that this roadmap will provide references on technology and methods to experimental users, as well as prospects for future development of technologies based on large research infrastructure facilities. Comprehensive studies and guidelines for basic research to practical application in various disciplines can be made with the assistance of large scientific facilities.

关键词： large scientific facilities synchrotron radiation FEL light sources neutron sources spectroscopic analysis methods X-ray imaging techniques structural information chemical dynamics

O2O外卖价格促销策略对消费者购买意愿的影响研究

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中国管理科学 2024年第2期32卷 254-264页

作者：钟琦曲冠桥唐加福东北财经大学管理科学与工程学院辽宁大连116025 国际商业机器全球服务(大连)有限公司辽宁大连116044

O2O外卖行业如何通过差异化促销策略提升用户体验、提高购买意愿,是O2O外卖平台和餐饮商家十分关注的问题。O2O外卖常见的价格促销方式有13种,本文将其梳理归纳为三类促销策略:优惠券类、折扣类和附加服务费优惠类。基于刺激-机体-反应... 详细信息

O2O外卖行业如何通过差异化促销策略提升用户体验、提高购买意愿,是O2O外卖平台和餐饮商家十分关注的问题。O2O外卖常见的价格促销方式有13种,本文将其梳理归纳为三类促销策略:优惠券类、折扣类和附加服务费优惠类。基于刺激-机体-反应模型(SOR模型),引入感知促销价值因素,建立O2O外卖价格促销策略对消费者购买意愿影响机制的理论模型;通过问卷星在线收集567份样本数据并进行结构方程模型分析,针对不同价格促销策略对潜在消费者购买意愿的影响路径和作用机制进行实证检验,并验证感知促销利益和感知促销成本的中介效应。研究结果表明,在三类价格促销策略中,优惠券类促销策略对潜在消费者购买意愿的影响最大;附加服务费优惠类促销策略对于O2O外卖消费者的购买意愿影响不大;与优惠券类促销策略直接促使消费者做出购买决策不同,折扣类促销策略下消费者需要对感知促销成本和感知促销利益进行权衡后做出最终购买决策。研究结论为O2O外卖平台和餐饮商家改进现有促销策略提供理论依据和参考。

关键词： O2O外卖价格促销策略 SOR模型购买意愿

The In-Flight Realtime Trigger and Localization Software of GECAM

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Research in Astronomy and Astrophysics 2024年第10期24卷 11-24页

作者： Xiao-Yun Zhao Shao-Lin Xiong Xiang-yang Wen Xin-qiao Li Ce Cai Shuo Xiao Qi Luo Wen-Xi Peng Dong-Ya Guo Zheng-Hua An Ke Gong Jin-Yuan Liao Yan-Qiu Zhang Yue Huang Lu Li Xing Wen Fei Zhang Jing Duan Chen-Wei Wang Dong-Li Shi Peng Zhang Qi-Bin Yi Chao-yang Li Yan-Bing Xu Xiao-Hua Liang Ya-Qing Liu Da-Li Zhang Xi-Lei Sun Fan Zhang Gang Chen Huan-Yu Wang Sheng yang Xiao-Jing Liu Min Gao Mao-Shun Li Jin-Zhou Wang Xing Zhou Yi Zhao Wang-Chen Xue Chao Zheng jia-Cong Liu Xing-Bo Han Jin-Ling Qi jia Huang Ke-Ke Zhang Can Chen Xiong-Tao yang Dong-Jie Hou Yu-Sa Wang Rui qiao Xiang Ma Xiao-Bo Li Ping Wang Xin-Ying Song Li-Ming Song Shi-Jie Zheng Bing Li Hong-Mei Zhang Yue Zhu Wei Chen jian-jian He Zhen Zhang Jin Hou Hong-Jun Wang Yan-Chao Hao Xiang-Yu Wang Zong-Yuan yang Zhi-Long Wen Zhi Chang Yuan-Yuan Du Rui Gao Xiao-Fei Lan Yan-Guo Li Gang Li Xu-Fang Li Fang-Jun Lu Hong Lu Bin Meng Feng Shi Hui Wang Hui-Zhen Wang Yu-Peng Xu jia-Wei yang Xue-Juan yang Shuang-Nan Zhang Chao-Yue Zhang Cheng-Mo Zhang Zhi-Cheng Tang Cheng Cheng Key Laboratory of Particle Astrophysics Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China University of Chinese Academy of Sciences Chinese Academy of SciencesBeijing 100049China School of Information Science and Technology Southwest Jiaotong UniversityChengdu 611756China Key Laboratory of Stellar and Interstellar Physics and Department of Physics Xiangtan UniversityXiangtan 411105China Physics and Space Science College China West Normal UniversityNanchong 637002China Department of Astronomy Beijing Normal UniversityBeijing 100875China Innovation Academy for Microsatellites of CAS Shanghai 201203China Changchun University of Science and Technology Changchun 130022China Chinese Academy of Sciences South America Center for Astronomy National Astronomical ObservatoriesCASBeijing 100101China

Realtime trigger and localization of bursts are the key functions of GECAM,an all-sky gamma-ray monitor launched on 2020 December *** developed a multifunctional trigger and localization software operating in the CPU of the GECAM Electronic *** onboard software has the following features:high trigger efficiency for real celestial bursts with a suppression of false triggers caused by charged particle bursts and background fluctuation,dedicated localization algorithm optimized for both short and long bursts,and low time latency of the trigger information which is downlinked through the Global Short Message Communication service of the global BeiDou navigation *** paper provides a detailed description of the design and development of the trigger and localization software system for *** covers the general design,workflow,the main functions,and the algorithms used in the *** paper also includes on-ground trigger tests using simulated gamma-ray bursts generated by a dedicated X-ray tube,as well as an overview of the performance for real celestial bursts during its in-orbit operation.

关键词： telescopes instrumentation:detectors methods:observational

Strong Anisotropic Order Parameters at All-Nitride Ferromagnet/Superconductor Interfaces

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Chinese Physics Letters 2024年第2期41卷 102-111页

作者： qiao Jin Meng yang Guozhu Song Nan Zhao Shengru Chen Haitao Hong Ting Cui Dongke Rong Qianying Wang Yiyan Fan Chen Ge Can Wang jiachang Bi Yanwei Cao Liusuo Wu Shanmin Wang Kui-Juan Jin Zhi-Gang Cheng Er-jia Guo Beijing National Laboratory for Condensed Matter Physics and Institute of PhysicsChinese Academy of SciencesBeijing 100190China Department of Physics&Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China Department of Physics Southern University of Science and TechnologyShenzhen 518055China Songshan Lake Materials Laboratory Dongguan 523808China Ningbo Institute of Materials Technology&Engineering Chinese Academy of SciencesNingbo 315201China

Proximity effects between superconductors and ferromagnets(SC/FM)hold paramount importance in comprehending the spin competition transpiring at their *** competition arises from the interplay between Cooper pairs and ferromagnetic exchange *** proximity effects between transition metal nitrides(TMNs)are scarcely investigated due to the formidable challenges of fabricating high-quality SC/FM *** fabricated heterostructures comprising SC titanium nitride(TiN)and FM iron nitride(Fe_(3)N)with precise chemical compositions and atomically well-defined *** magnetoresistance of Fe_(3)N/TiN heterostructures shows a distinct magnetic anisotropy and strongly depends on the external ***,the superconducting transition temperatureT_(C) and critical field of TiN experience notable suppression when proximity to Fe_(3)*** observe the intriguing competition of interfacial spin orientations near𝑇T_(C)(∼1.25 K).These findings not only add a new materials system for investigating the interplay between superconductor and ferromagnets,but also potentially provide a building block for future research endeavors and applications in the realms of superconducting spintronic devices.

关键词： proximity Superconductor titanium