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Design and technology review of the solar X-ray detector onboard the Macao science Satel{2.te-1B

science china Technological {2. 2024年第11期67卷 3365-3380页

作者： ZUO FuChang SHI YongQiang CHEN JianWu ZHANG XiaoPing FU WeiChun CHANG Ye GAI FangQin liU SiYuan XIONG Yan ZHANG Haili SUN Yan {2. li zheng Ran li lianSheng MEI ZhiWu HUANG He ZHA GangQiang ZHANG KeKe space Optoelectronic Measurement and Perception Lab. Beijing Institute of Control Engineering State Key Laboratory of Lunar and Planetary sciences Macau University of Science and Technology school of Astronautics Northwestern Polytechnical University Key Laboratory of Radiation Detection Materials and Devices Northwestern Polytechnical University Research and Development Institute of Northwestern Polytechnical university in Shenzhen

On May 2., 2.2., the Macao {3. Satellite-1B(MSS-1B), a low-inclination, low-latitude, and high-precision scientific exploration satellite for geomagnetic fields and space environments, was successfully launched. The solar X-ray detector(SXD),one of the two major scientific payloads onboard the MSS-1B, has obtained a large amount of solar X-ray radiation data, which reveals the distribution law of the magnetic field in the low {2. orbit, as well as the coupling law of the {2.'s magnetic field and the solar radiation and energy particle distributions. First, the overall design of the multi-detection-unit, broad-energy-range,small-volume, and low-power SXD was implemented to achieve the scientific objectives of the mission. Second, the technical indicators of the instrument were decomposed into various components, and the key technologies, such as collimator, processing circuit, thermal, and payload dataset designs, were reviewed. Third, the backgrounds, including electronic noise, cosmic diffuse X-ray background, and high-energy background in the {2.'s radiation belts in and out of the field of view, were analyzed for the instrument. Then, the ground calibrations of the energy response, detection efficiency, and temperature-dependent peak drift of the SXD flight model were conducted. Finally, the in-orbit temperature, energy spectrum data, background, and solar flare process observation of the instrument in the in-orbit test stage are presented, verifying the instrument design, analysis, and ground calibration, providing a foundation for obtaining accurate solar X-ray radiation data, and achieving the scientific objectives of the satellite.

关键词： Macao science Satellite-1B solar X-ray detector design and development solar flare technology review

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类岩石试件三轴扰动破坏特性试验研究

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采矿与岩层控制工程学报 2024年第2期6卷 11-24页

作者：王军朱传根李勋王波张艺腾山东建筑大学土木工程学院山东济南250101 山东建筑大学建筑结构加固改造与地下空间工程教育部重点实验室山东济南250101 华北科技学院应急技术与管理学院北京101601 应急管理部信息研究院北京100029

为研究高应力围岩扰动破坏机制,开展了不同围压下类岩石试件的三轴常规压缩和三轴循环扰动试验,得到了试件的扰动应力–应变规律和变形破坏特征,并对试件开展了核磁共振(Nuclear Magnetic Resonance)成像试验,从微观角度进一步阐明了试... 详细信息

为研究高应力围岩扰动破坏机制,开展了不同围压下类岩石试件的三轴常规压缩和三轴循环扰动试验,得到了试件的扰动应力–应变规律和变形破坏特征,并对试件开展了核磁共振(Nuclear Magnetic Resonance)成像试验,从微观角度进一步阐明了试件扰动破坏机理。研究结果表明:(1)试件在不同围压下均存在一个阈值强度,轴向荷载超过阈值强度后,轴向变形对扰动变得敏感,再次施加扰动会引起试件显著变形,当轴向荷载低于阈值强度时,变形对扰动不敏感。阈值强度与极限强度的比值可以反映试件的抗扰动能力,随着围压增大,该比值呈现逐步递减的规律,说明高围压下试件抗扰动能力下降,对扰动作用更敏感。(2.扰动作用下类岩石试件存在弱化效应,如常规三轴10MPa围压下试件表现出腰鼓破坏,而受扰动作用后,试件呈现斜切脆性破坏,与常规三轴5MPa围压下破坏形态相近。(3.岩石试件在高应力作用下进入塑性流动状态,内部颗粒重新排列,内部小孔隙与大孔隙的占比减少,而中孔隙的占比显著增多,试件内部孔隙率整体降低。

关键词：类岩石试件三轴扰动阈值强度破坏形态核磁共振

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A Single-Board Integrated Millimeter-Wave Asymmetric Full-Digital Beamforming Array for B5G/6G Applications

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Engineering 2024年第10期41卷 35-50页

作者： Qingqing lin jun Xu Kai Chen Long {2. Wei li Zhiqiang Yu Guangqi Yang Jianyi Zhou Zhe Chen Jixin Chen Xiaowei Zhu Wei Hong State Key Laboratory of Millimeter Waves School of Information Science and EngineeringSoutheast UniversityNanjing 210096China Purple Mountain Laboratories Nanjing 211111China Frontiers science Center for Mobile Information Communication and Security Southeast UniversityNanjing 210096China

In this article,a single-board integrated millimeter-wave(mm-Wave)asymmetric full-digital beamforming(AFDBF)array is developed for beyond-fifth-generation(B5G)and sixth-generation(6G)*** proposed integrated array effectively addresses the challenge of arranging a large number of ports in a full-digital array by designing vertical connections in a three-dimensional {3. and successfully integrating full-digital transmitting(Tx)and receiving(Rx)arrays independently in a single *** the traditional symmetric array,the proposed asymmetric array is composed of an 8×8 Tx array arranged in a square shape and an 8+8 Rx array arranged in an L *** center-to-center distance between two adjacent elements is 0.54k0 for both the Tx and Rx arrays,where k0 is the free-{3. wavelength at 2. *** proposed AFDBF array possesses a more compact structure and lower system hardware cost and power consumption compared with conventional brick-type full-digital *** addition,the energy efficiency of the proposed AFDBF array outperforms that of a hybrid beamforming *** measurement results indicate that the operating frequency band of the proposed array is 2..2.–2..50 *** eight-element linear array within the Tx array can achieve a scanning angle ranging from-47°to+47°in both the azimuth and the elevation planes,and the measured scanning range of each eight-element Rx array is–45°to+45°.The measured maximum effective isotropic radiated power(EIRP)of the eight-element Tx array is 43.2.dBm at 2..0 GHz(considering the saturation point).Furthermore,the measured error vector magnitude(EVM)is less than 3.when 64-quadrature amplitude modulation(QAM)waveforms are used.

关键词： Full-digital beamforming array Asymmetric structure Single-board integrated Beyond fifth-generation and sixthgeneration Millimeter-wave communication Complex modulation Printed circuit board Vertical connection

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Partial melting of carbonated mantle: element and isotope evidence from Cenozoic continental basalt in east-central china

Partial melting of carbonated mantle: element and isotope ev...

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International Conference on Continental Volcanism

作者： Yong-Fei zheng. Zi-Fu Zhao jun-jun Zhang Xia-Chen Zhi Yi-{3.ang {3. and Bing Gong CAS Kay Laboratory of Crust-Mantle Materials and Environments school of {2. and {3. sciences university of science and technology of {12. Hefei 2.002. {12.

＜正＞Although high-pressure experiments have suggested that OIB-like alkalic basalts can originate from partial melting of carbonated peridotite, no continental basalt is tested to fit such an origin. A combined study of trace elements and Nd-Sr-O-C isotopes were carried out on Miocene continental basalts at eastern Anhui in east-central {2.. The results suggest that the continental basalts were derived from partial melting of carbonated, fertile mantle source.

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Robust measurement of orbital angular momentum of a partially coherent vortex beam under amplitude and phase perturbations

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Opto-Electronic science 2024年第1期3卷 1-12页

作者： Zhao Zhang Gaoyuan li Yonglei liu Haiyun {2. Bernhard J.Hoenders Chunhao liang Yangjian Cai jun Zeng Shandong Provincial Engineering and Technical Center of light Manipulations&Shandong Provincial Key Laboratory of Optics and Photonic Device School of Physics and ElectronicsShandong Normal UniversityJinan 250358China Collaborative Innovation Center of light Manipulation and Applications Shandong Normal UniversityJinan 250358China school of Physical science and {2. Soochow UniversitySuzhou 215006China school of Physical science and {2. Suzhou University of Science and TechnologySuzhou 215009China Zernike Institute for Advanced Materials University of GroningenNijenborgh 4NL-9747 AG GroningenThe Netherlands Joint Research Center of light Manipulation science and Photonic Integrated Chip of East {2. Normal {3. and Shandong Normal {3. East China Normal UniversityShanghai 200241China

The ability to overcome the negative effects,induced by obstacles and turbulent atmosphere,is a core challenge of long-distance information transmission,and it is of great significance in free-space optical *** spatial-cohe{2.ce structure,that characterizes partially cohe{2.t fields,provides a new degree of freedom for carrying ***,due to the influence of the complex transmission environment,the spatial-cohe{2.ce structure is severely damaged during the propagation path,which undoubtedly limits its ability to transmit ***,we realize the robust far-field orbital angular momentum(OAM)transmission and detection by modulating the spatial-cohe{2.ce structure of a partially cohe{2.t vortex beam with the help of the *** cross-phase enables the OAM information,quantified by the topological charge,hidden in the spatial-cohe{2.ce structure can be stably transmitted to the far field and can resist the influence of obstructions and turbulence within the communication *** is due to the self-reconstruction property of the spatial-cohe{2.ce structure embedded with the *** demonstrate experimentally that the topological charge information can be recognized well by measuring the spatial-cohe{2.ce structure in the far field,exhibiting a set of distinct and separated dark rings even under amplitude and phase *** findings open a door for robust optical signal transmission through the complex environment and may find application in optical communication through a turbulent atmosphere.

关键词： degree of coherence orbital angular momentum cross-phase topological charge information transmission

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Association between Long-Term Exposure to PM_(2.5) Inorganic Chemical Compositions and Cardiopulmonary Mortality: A 2.-Year Cohort Study in Northern {3.

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Environment & Health 2024年第8期2卷 530-540页

作者： Hongyue Sun Xi Chen Wenzhong Huang Jing Wei Xueli Yang Anqi Shan liwen Zhang Honglu Zhang Jiayu He Chengjie Pan Jingjing li Jing Wu Tong {3. Jie Chen Yuming Guo Shilu Tong Guanghui Dong Nai-jun Tang Department of Occupational and Environmental Health School of Public HealthTianjin Medical UniversityTianjin 300070China Tianjin Key Laboratory of Environment Nutrition and Public Health Tianjin Medical UniversityTianjin 300070China Center for International Collaborative Research on Environment Nutrition and Public Health Tianjin 300070China Key Laboratory of Prevention and Control of Major Diseases in the Population Ministry of EducationTianjin Medical UniversityTianjin 300070China Climate Air Quality Research UnitSchool of Public Health and Preventive MedicineMonash UniversityMelbourne 3004Australia Department of Atmospheric and Oceanic science Earth System Science Interdisciplinary CenterUniversity of MarylandCollege ParkMaryland 20740United States Shandong Provincial Hospital Affiliated to Shandong First Medical university Ji nan 250021ShandongChina National Center for Chronic and Noncommunicable Disease Control and Prevention Chinese Center for Disease Control and PreventionBeijing 100050China Department of Epidemiology and Biostatistics School of Public HealthTianjin Medical UniversityTianjin 300070China school of Public Health Shanxi Medical UniversityTaiyuan 030001China school of Public Health and Social Work Queensland University of TechnologyBrisbane 4072QLD Australia National Institute of Environmental Health Chinese Centre for Disease Control and PreventionBeijing 100021China Guangdong Provincial Engineering technology Research Center of Environmental Pollution and Health Risk Assessment Department of Occupational and Environmental HealthSchool of Public HealthSun Yat-sen UniversityGuangzhou 510080China

Particulate matter with diameters≤2.5μm(PM_(2.5))has been identified as a significant air pollutant contributing to premature ***,the specific compositions within PM_(2.5) that play the most crucial role remain unclear,especially in areas with high pollution *** study aims to investigate the individual and joint morta{3.ty risks associated with PM_(2.5) inorganic chemical compositions and identify primary *** 1998,we conducted a prospective cohort study in four northern Chinese cities(Tianjin,Shenyang,Taiyuan,and Rizhao).Satel{3.te-based machine learning models calculated PM_(2.5) inorganic chemical compositions,including sulfate(SO_(4)^(2.)),nitrate(NO_(3.^(–)),ammonium(NH_(4)^(+)),and chloride(Cl^(-)).A time-varying Cox proportional hazards model was app{3.ed to analyze associations between these compositions and cardiorespiratory morta{3.ty,encompassing nonaccidental causes,cardiovascular diseases(CVDs),nonma{3.gnant respiratory diseases(RDs),and lung *** quantile-based g-computation model evaluated joint exposure effects and relative contributions of the *** analysis was used to identify vulnerable *** 785,807 person-years of follow-up,5812.15.5%)deaths occurred from nonaccidental causes,including 2.3.0}7.8%)from all CVDs,479(1.3.)from nonma{3.gnant RDs,and 552.1.4%)from lung *** interquartile range(IQR)increase in SO_(4)^(2.)was associated with morta{3.ty from nonaccidental causes(hazard ratio:1.860;95%confidence interval:1.809,1.911),CVDs(1.909;1.83.,1.985),nonma{3.gnant RDs(2.178;1.975,2.403.,and lung cancer(1.773.1.62.,1.93.).In the joint exposure model,a simultaneous rise of one IQR in all four compositions increased the risk of cardiorespiratory morta{3.ty by at least 3..3.,with long-term exposure to SO_(4)^(2.)contributing the most to nonaccidental and cardiopulmonary *** with higher incomes and lower education levels were found to be more vulnerable.

关键词： PM_(2.5)inorganic chemical compositions mortality cohort study cardiorespiratory disease joint association

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lithium isotopic composition of subduction-related leucogranites and associated rocks from the northern margin of the North china craton:Source tracking and tectonic implications

Lithium isotopic composition of subduction-related leucogran...

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中国矿物岩石地球化学学会第13.学术年会

作者： XIAO Yi-lin~1,XU li-{2.~1,GAO Yong-{2.~2.li Shu-guang~1, SUN He~1,GU Hai-ou~1 1.CAS Key Laboratory of Crust-Mantle Materials and Environments,school of earth and {2. {3.,university of science and technology of {12.,Hefei,2.002. 2.Department of earth and Atmospheric {3.,university of Houston,Houston,TX 772.4,USA

We report li elemental and isotopic data for a suite of(leuco-) granitic and gneissic rocks(presumed protolith of the leucogranite) from the boundary between the North {2. craton(NCC) and the South {2. plate (SCP),which represent an important repository for understanding the Mesozoic thicken and thinning processes of the *** concentrations and isotopic compositions of leucogranites from the Bangbu area in the southern margin of the NCC show the following important characteristics:i) most samples(15 out of 19) have much lower li concentrations but higherδ li values compared to normal granite;ii) some samples have very low li concentrations(around 1 ppm) but extremely heavy isotopic compositions(from 8.6 to 16.1),representing the heaviest li isotopic compositions so far reported for granitic rocks;iii) lithium isotopic compositions of 11

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基于杂波和噪声联合稀疏特性的直接数据域STAP方法

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系统工程与电子技术 2024年第9期46卷 2980-2987页

作者：汪亚龙王嘉恒李军何勤何子述电子科技大学信息与通信工程学院四川成都611731

针对机载预警雷达空时自适应处理(space-time adaptive processing,STAP)所面临的异构杂波环境,基于杂波和噪声的联合稀疏特性提出了一种直接数据域(direct data domain,D3.STAP方法。首先通过子孔径平滑技术扩充训练样本集合;然后基于... 详细信息

针对机载预警雷达空时自适应处理(space-time adaptive processing,STAP)所面临的异构杂波环境,基于杂波和噪声的联合稀疏特性提出了一种直接数据域(direct data domain,D3.STAP方法。首先通过子孔径平滑技术扩充训练样本集合;然后基于杂波谱二阶表征理论构造STAP功率字典矩阵、导出目标函数,并解得待检测单元信号的空时功率谱;最后根据杂波先验信息重构无孔径损失的杂波加噪声协方差矩阵。数值实验验证了所提方法的协方差矩阵估计精度高于传统的稀疏恢复D3.STAP算法,且在理想情况和存在阵列误差的情况下,所提方法皆具备更好的低速目标检测性能。

关键词：空时自适应处理直接数据域联合稀疏特性杂波谱二阶表征

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1.2. μm O_(2.(a^(1)Δ g)气辉临边观测辐射传输特性

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光谱学与光谱分析 2024年第4期44卷 1088-1097页

作者：王道琦王后茂何微微胡向瑞李娟李发泉武魁军烟台大学物理与电子信息学院山东烟台264005 中国科学院国家空间科学中心北京100190 中国科学院西安光学精密机械研究所陕西西安710119 中国科学院精密测量科学与技术创新研究院湖北武汉430071

1.2.μm波段的O_(2.(a^(1)Δg)气辉辐射具有辐射信号强、空间跨度大、自吸收效应弱等诸多内禀优势,是临近空间大气遥感的重要目标源,对于中高层大气的动力学及热学特性研究,全球温室气体探测,以及臭氧浓度三维层析等卫星遥感具有重要的... 详细信息

1.2.μm波段的O_(2.(a^(1)Δg)气辉辐射具有辐射信号强、空间跨度大、自吸收效应弱等诸多内禀优势,是临近空间大气遥感的重要目标源,对于中高层大气的动力学及热学特性研究,全球温室气体探测,以及臭氧浓度三维层析等卫星遥感具有重要的科学意义和应用价值。首先基于O_(2.(a^(1)Δg)光化学反应模型,研究了O_(2.(a^(1)Δg)气辉的产生机制及湮灭机理,在此基础上,计算得到了O_(2.(a^(1)Δg)气辉体辐射率廓线,并基于HITRAN数据库给出的谱线强度及爱因斯坦系数,提出了两种计算O_(2.(a^(1)Δg)气辉光谱分布的方法。采用最新的分子光谱参数、光化学反应速率常数及F10.7太阳紫外通量等参数,结合光化学反应模型计算得到的O_(2.(a^(1)Δg)气辉体辐射率廓线信息,借助逐线积分算法,建立了1.2.μm O_(2.(a^(1)Δg)气辉临边观测辐射传输理论模型,并分析了自吸收效应对不同临边观测高度处气辉辐射光谱强度的影响。然后,利用剥洋葱算法,对大气图像扫描成像吸收光谱仪(SCIAMACHY)在临边观测模式下测得的O_(2.分子近红外大气带的气辉辐射信号进行处理得到了目标层O_(2.(a^(1)Δg)气辉辐射光谱,并通过谱积分算法反演得到了O_(2.(a^(1)Δg)气辉的体辐射率廓线信息。最后通过对比气辉临边观测辐射传输理论模型计算得到的以及SCIAMACHY仪器测量反演得到的1.2.μm O_(2.(a^(1)Δg)辐射光谱及体辐射率廓线信息,验证1.2.μm O_(2.(a^(1)Δg)气辉临边观测辐射传输理论模型的可靠性与合理性。基于比对结果,对O_(2.(a^(1)Δg)气辉临边辐射强度和体辐射率的影响因素进行了分析。分析结果表明,在50 km以上的高空区域,理论计算结果与卫星实测结果吻合性较好,而随着海拔高度的降低,两者的偏差逐渐增大,这是因为在临边观测模式下,中低空区域的卫星遥感信号受自吸收效应及大气散射效应影响严重。此外,与HITRAN数据库给出的谱线强度参数相比,基于爱因斯坦系数建立的O_(2.(a^(1)Δg)气辉临边辐射模型与卫星实测结果更加吻合。1.2.μm O_(2.(a^(1)Δg)气辉临边观测辐射传输理论模型的建立,对于临近空间大气遥感,奠定了理论基础。

关键词： O_(2.(a^(1)Δg)气辉体辐射率临边观测辐射传输理论模型

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降水驱动下大港河硝酸盐迁移转化过程及来源解析

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中国环境科学 2024年第1期44卷 288-299页

作者：王俊亢晓琪吴亚丽牛远余辉中国环境科学研究院湖泊生态环境研究所北京100012 河南农业大学资源与环境学院河南郑州450002 天津大学地球系统科学学院表层地球系统科学研究院天津300072

为定量识别大港河流域硝酸盐来源的贡献,在降水条件下,对秋季(2.2.年11月)和春季(2.2.年3.)典型月份在大港河流从上游山林农业区到下游湖滨区共布设8个河水及沉积物监测点,其中包含地下水、生活污水及畜禽粪便、山林农业区和流域土壤... 详细信息

为定量识别大港河流域硝酸盐来源的贡献,在降水条件下,对秋季(2.2.年11月)和春季(2.2.年3.)典型月份在大港河流从上游山林农业区到下游湖滨区共布设8个河水及沉积物监测点,其中包含地下水、生活污水及畜禽粪便、山林农业区和流域土壤等2.个硝酸盐氮源监测点,通过大港河水体水化学分析、结合硝酸盐氮氧双同位素示踪技术和贝叶斯混合模型,探究了大港河流域水体硝酸盐来源及迁移转化过程,确定了各硝酸盐源的贡献.结果表明:(1)秋季和春季大港河流域水体中TN浓度均值分别为3.2.和3.2.mg/L,劣于地表水环境质量Ⅴ类标准,NO_(3.^(-)-N是影响水体水质氮素超标的主要赋存形式;(2.降水的驱动作用影响大港河流域硝酸盐浓度的季节变化,流域氮循环过程以硝化作用为主,多种氮转化过程共同发生;(3.生活污水或畜禽粪便对流域水体的硝酸盐为主要贡献,其贡献率在秋季和春季分别为40.8%±3.0}8%和55.8%±2..3.,其次是地下水和流域土壤,降水对流域硝酸盐的贡献作用始终最小.

关键词：降水大港河流域氮氧双同位素硝酸盐来源贝叶斯混合模型来源解析

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