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Multiphysics simulation and optimization of the in-situ beneficiation process of ilmenite minerals from lunar regolith

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Science China Earth Sciences 2025年第1期68卷 195-207页

作者： Peng ZHANG Xin liu Guanghui liu Wei DAI Hanzhe YANG Haibo ZHENG Zhi WANG Ran NIU Yifan BAI Yang ZHANG Chengbao liu Ge YANG Junwei YANG Guang ZHANG Technology and Engineering Center for Space Utilization Chinese Academy of Sciences Beijing Hegong Simulation Co. Ltd

The exploration and utilization of lunar resources have become the major objectives of future lunar exploration missions. The classified collection and processing of lunar minerals is the basic prerequisite for the in-situ exploration and utilization of lunar resources. In this study, we propose a scheme for in-situ separation of magnetic minerals from lunar soils using the dry magnetic separation method. The scheme can realize the purpose of separating magnetic minerals from lunar regolith by altering the motion trajectory of lunar regolith particles with different magnetic properties. Detailed modeling of the dry magnetic separation device is conducted, and the three-dimensional distribution of magnetic parameters is calculated and analyzed. Based on the characterization and analysis of the Chang E-5's samples, the morphologies and physical parameters of lunar regolith particles are modeled and simulated. A discrete element simulation of the motion process of lunar regolith particles under multi-physical field conditions is performed, and the influences of key parameters on the beneficiation performance of lunar magnetic minerals are investigated. Our results indicate that optimal separation and beneficiation of lunar regolith particles can be achieved under specific conditions of magnetic field strength and drum speed. Additionally, we analyze the effects of lunar weak gravity conditions and the charged nature of lunar particles on the beneficiation process, showing that these factors can obviously enhance the beneficiation process of lunar ilmenites. This study demonstrates the feasibility of using the dry magnetic separation method for the beneficiation of magnetic minerals from lunar regolith, providing a theoretical basis for the scientific tasks of collecting, processing, and utilizing lunar mineral resources.

关键词： Lunar regolith In-situ resource utilization Magnetic separation Classified sampling

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雷达/通信信号侦察一体化技术

舰船电子对抗 2008年第2期31卷 5-11页

作者：李朝伟周希元刘福来中国电子科技集团公司第54研究所石家庄050081

为对抗日益复杂的电磁环境,适应一体化综合电子战发展的需要,对单平台雷达/通信侦察一体化技术进行了研究。从电磁频段、功能、功率、信号波形及调制方式等不同角度,详细地分析了雷达与通信信号的特点;对实现雷达/通信侦察一体化的一体... 详细信息

为对抗日益复杂的电磁环境,适应一体化综合电子战发展的需要,对单平台雷达/通信侦察一体化技术进行了研究。从电磁频段、功能、功率、信号波形及调制方式等不同角度,详细地分析了雷达与通信信号的特点;对实现雷达/通信侦察一体化的一体化微波前端技术、一体化数字接收机技术、一体化数字信号处理技术、模块化技术等关键技术进行了研究,尤其是对一体化信号分选、识别技术进行了深入的分析研究。

关键词：雷达信号通信信号一体化技术模块化技术

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便携式可见分光光度计测定桂圆中二氧化硫

分析仪器 2017年第4期 162-165页

作者：窦宏亮刘鑫高峰刘亚芹云环刘萤刘来福北京普析通用仪器有限公司北京101200 北京出入境检验检疫局北京100026

采用便携式可见分光光度计测定桂圆中二氧化硫含量。结果表明,二氧化硫在0~120mg/kg范围内线性关系为y=0.99Abx-0.007,相关系数为0.999;重复性为9.0%。与实验室检测数据相比偏差为2.2%~9.0%。实验证明便携式可见分光光度计测定桂圆中二... 详细信息

采用便携式可见分光光度计测定桂圆中二氧化硫含量。结果表明,二氧化硫在0~120mg/kg范围内线性关系为y=0.99Abx-0.007,相关系数为0.999;重复性为9.0%。与实验室检测数据相比偏差为2.2%~9.0%。实验证明便携式可见分光光度计测定桂圆中二氧化硫的结果与实验室测定结果相当,可以用于桂圆中二氧化硫含量。

关键词：二氧化硫快速检测便携式可见分光光度计

Applications of in-situ solid-state nuclear magnetic resonance in methanol to olefins reaction

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Science China Chemistry 2025年第1期68卷 134-151页

作者： Jing Niu Shutao Xu Yingxu Wei Zhongmin liu National Engineering Research Center of Lower-Carbon Catalysis Technology Dalian Institute of Chemical PhysicsChinese Academy of Sciences State Key Laboratory of Catalysis Dalian Institute of Chemical Physics Chinese Academy of Sciences University of Chinese Academy of Sciences

The methanol-to-olefins（MTO） reaction offers an alternative pathway for the production of low-carbon olefins from non-oil feedstocks. fundamental research has been impeded by a lack of comprehensive understanding of its underlying mechanism,despite the significant progress made in industry. In-situ solid-state nuclear magnetic resonance（ss NMR） spectroscopy has emerged as a pivotal tool, offering crucial insights into key species under real-time operando conditions. furthermore, the host–guest interaction between zeolites or surface species residing on zeolites and the reactant/active intermediates is revealed by the combination of in-situ13C MAS NMR and 2D correlation spectroscopy. Moreover, recent technological advancements in hyperpolarization（HP） methods, including HP129Xe NMR and dynamic nuclear polarization（DNP）, have significantly improved the sensitivity of ss NMR, enabling detailed structural and kinetic analysis as well as the detection of trace species. In this feature article, we summarized recent advancements in（in-situ） ss NMR spectroscopy applied to MTO reaction processes,encompassing mechanistic investigations at various stages and the intricate host–guest interactions. These theoretical insights into the dynamic evolution of MTO reactions lay a solid foundation for the optimization of catalytic processes and the development of efficient catalysts, thereby advancing the techniques towards more sustainable and economical production route for olefins.

关键词： MTO zeolites in-situ ssNMR reactive intermediates reaction mechanism

Single-cell omics: experimental workflow, data analyses and applications

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Science China Life Sciences 2025年第1期68卷 5-102页

作者： Fengying Sun Haoyan Li Dongqing Sun Shaliu fu Lei Gu Xin Shao Qinqin Wang Xin Dong Bin Duan Feiyang Xing Jun Wu Minmin Xiao Fangqing Zhao Jing-Dong J.Han Qi liu Xiaohui Fan Chen Li Chenfei Wang Tieliu Shi Department of Clinical Laboratory the Affiliated Wuhu Hospital of East China Normal University (The Second People's Hospital of Wuhu City) Pharmaceutical Informatics Institute College of Pharmaceutical SciencesZhejiang University Key Laboratory of Spine and Spinal Cord Injury Repair and Regeneration (Tongji University) Ministry of EducationOrthopaedic DepartmentTongji HospitalBioinformatics DepartmentSchool of Life Sciences and TechnologyTongji University Frontier Science Center for Stem Cells School of Life Sciences and TechnologyTongji University Translational Medical Center for Stem Cell Therapy and Institute for Regenerative Medicine Shanghai East HospitalBioinformatics DepartmentSchool of Life Sciences and TechnologyTongji University Research Institute of Intelligent Computing Zhejiang Lab Shanghai Research Institute for Intelligent Autonomous Systems Center for Single-cell Omics School of Public HealthShanghai Jiao Tong University School of Medicine National Key Laboratory of Chinese Medicine Modernization Innovation Center of Yangtze River DeltaZhejiang University Center for Bioinformatics and Computational Biology Shanghai Key Laboratory of Regulatory Biologythe Institute of Biomedical Sciences and School of Life SciencesEast China Normal University Beijing Institutes of Life Science Chinese Academy of Sciences Peking-Tsinghua Center for Life Sciences Academy for Advanced Interdisciplinary StudiesCenter for Quantitative Biology (CQB)Peking University Zhejiang Key Laboratory of Precision Diagnosis and Therapy for Major Gynecological Diseases Women's HospitalZhejiang University School of Medicine Key Laboratory of Advanced Theory and Application in Statistics and Data Science-MOE School of StatisticsEast China Normal University

Cells are the fundamental units of biological systems and exhibit unique development trajectories and molecular features. Our exploration of how the genomes orchestrate the formation and maintenance of each cell, and control the cellular phenotypes of various organismsis, is both captivating and intricate. Since the inception of the first single-cell RNA technology, technologies related to single-cell sequencing have experienced rapid advancements in recent years. These technologies have expanded horizontally to include single-cell genome, epigenome,proteome, and metabolome, while vertically, they have progressed to integrate multiple omics data and incorporate additional information such as spatial sc RNA-seq and CRISPR screening. Single-cell omics represent a groundbreaking advancement in the biomedical field,offering profound insights into the understanding of complex diseases, including cancers. Here, we comprehensively summarize recent advances in single-cell omics technologies, with a specific focus on the methodology section. This overview aims to guide researchers in selecting appropriate methods for single-cell sequencing and related data analysis.

关键词： single-cell sequencing genome epigenome proteomics metabolomics multimodal spatial transcriptomics CRISPR screening

Observation of topological charge transformations in acoustic vortex using passive periodic systems

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 140-147页

作者： Di-Chao Chen Xie liu Changqing Xu Da-Jian Wu Ying Cheng Xiao-Jun liu School of Physics and Technology Nanjing Normal University Key Laboratory of Modern Acoustics School of Physics Nanjing University

Vortex transmutation utilizes a periodic system, which not only enables the alteration of the topological charge(TC) of unstable input vortices but also facilitates their transformation into stable structures. This approach is crucial for investigating the characteristics of vortices in various wave systems. Here, we achieve acoustic vortex TC transmutation by employing a welldesigned dual-structured plate external system(DPES). The interactions between the acoustic vortex and the finite-order discrete rotational symmetry lead to the transformation of its topological charge when complete rotational symmetry is broken to Nthorder discrete symmetry. Our results experimentally demonstrate the acoustic vortex TC transmutation based on passive artificial structures, enabling numerous applications in particle manipulation and information multiplexing as well as advancing our understanding and control over free-space acoustic vortices.

关键词： acoustic vortex topological charge transformation artificial structure

Separation of the ionospheric and thermospheric contributions in the data from the Triple Ionosophere Photo Meter onboard the Feng-Yun 3E satellite

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Science China Earth Sciences 2025年第1期68卷 172-184页

作者： Fang JIANG Tian MAO Jin-Song WANG Xiu-Qing HU Xiao-Xin ZHANG Liping fu Nan JIA Tianfang WANG National Space Science Center Chinese Academy of Sciences Beijing Key Laboratory of Space Environment Exploration Key Laboratory of Environmental Space Situation Awareness Technology National Satellite Meteorological Center China Meteorological Administration

The Triple Ionosphere Photo Meter （TRIPM） is a far ultraviolet nadir-view photometer that is onboard the secondgeneration,polar-orbiting Chinese meteorological satellite Feng-Yun 3E （FY-3E）,which was launched on July 5,*** has three channels,and each is used to measure different types of emissions:（1） 135.6 nm airglow produced by the recombination of the O+ions and electrons in the absence of sunlight （nighttime channel）;（2） 135.6 nm airglow from the OI when sunlight is present （daytime/dusk-dawn 135.6 nm channel）;and （3） Airglow in the N2LBH of the TRIPM （daytime/dusk-dawn N2LBH channel）.FY-3E is a satellite operating in the early morning ***,the data are mostly distributed on the dawndusk side or at times when the solar zenith angle is relatively *** this study,combined with simulation calculations,the data are *** further explore the application value of the data products,a model is used to separate the ionospheric radiative recombination contribution from the thermosphere photoelectron impact excitation contribution in the data from the daytime/dusk-dawn 135.6 nm *** approach not only improves the accuracy of O/N2derived from the 135.6 nm channel and N2LBH channel but also provides the ionospheric 135.6 nm radiance at the same time as the *** results show that the 135.6 nm radiance originating from the combination of O+and electrons extracted from the measurement data exhibits similar equatorial anomaly peak structure characteristics and seasonal variations as the corresponding GPS total electron content （TEC） *** the other hand,the separated 135.6 nm radiance generated from the thermosphere photoelectron collision excitation does not contain radiative recombination contributions;thus,the ionosphere influence is greatly avoided when the O/N2is obtained.

关键词： Far ultraviolet 135.6 nm emission intensity Photoelectron impact excitation Radiative recombination excitation

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Bacterial indole-3-propionic acid inhibits macrophage IL-1β production through targeting methionine metabolism

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Science China Life Sciences 2025年

作者： Ziyi Han Jian fu Aiyan Gong Wenkai Ren State Key Laboratory of Livestock and Poultry Breeding College of Animal Science South China Agricultural University Animal Disease-resistant Nutrition Key Laboratory of Sichuan Province Sichuan Agricultural University China Institute of Veterinary Drug Control

The gut microbiota plays key roles in host health by shaping the host immune responses through their metabolites, like indole derivatives from tryptophan. However, the direct role of these indole derivatives in macrophage fate decision and the underlying mechanism remains unknown. Here, we found that bacterial indole-3-propionic acid(IPA) downregulates interleukin-1beta(IL-1β) production in M1 macrophages through inhibition of nuclear factor-kappa B(NF-κB) signaling. Mechanistically, IPA binds specifically with methionine adenosyltransferase 2A(MAT2A) to promote S-adenosylmethionine(SAM) synthesis, which facilitates the DNA methylation of ubiquitin-specific peptidase 16(USP16, a deubiquitinase), and in turn promotes Toll-like receptor 4(TLR4) ubiquitination and NF-κB inhibition. furthermore,IPA administration attenuates sepsis in mouse models induced by lipopolysaccharides(LPS), showcasing its potential as a microbial-derived adjunct in alleviating inflammation. Collectively, our findings reveal a newly found microbial metabolite-immune system regulatory pathway mediated by IPA.

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基于教学内容特点的混合式教学探索与实践--以非计算机专业的Java程序设计课程为例

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电脑与信息技术 2021年第6期29卷 78-82页

作者：李飞刘福来胡曦孙达明东北大学秦皇岛分校计算中心河北秦皇岛066000 唐山工业职业技术学院河北唐山064000

混合式教学模式是当前疫情趋于常态化背景下的一个研究热点。有效的混合式教学需要根据授课对象、授课目标与授课内容的特性进行合理设计。文章以“非计算机专业的Java程序设计课程”为例,结合非计算机专业学生的学习特点、课程教学目... 详细信息

混合式教学模式是当前疫情趋于常态化背景下的一个研究热点。有效的混合式教学需要根据授课对象、授课目标与授课内容的特性进行合理设计。文章以“非计算机专业的Java程序设计课程”为例,结合非计算机专业学生的学习特点、课程教学目标和知识点的教学特征,提出了线上线下教学内容的划分方法,进而给出一种基于教学内容特点的混合式教学体系。实践表明该体系的实施提高了学生的学习积极性和兴趣,进而提高学生的学习效率。

关键词：非计算机专业混合式教学计算机语言 Java 线上